Android Developer

Pro Tips for Optimizing Android Gradle Builds

noreply@blogger.com (Himanshu) — Sun, 23 Mar 2025 15:07:00 +0530

Following the configuration changes per your system RAM to make gradle build faster for the android project.

Step:-1 In gradle.properties turn on below line.

org.gradle.parallel=true: Excellent for parallel task execution.

Step:-2 gradle=build -x lint -x lintVitalBasicRelease

Good for development builds, excluding time-consuming lint checks. Remember to run these before release!

Step3: This is important one,Increase jvmargs memory

org.gradle.jvmargs=-Xmx8g -XX:MaxMetaspaceSize=512m -Dkotlin.daemon.jvm.options="-Xmx8g" -XX:+HeapDumpOnOutOfMemoryError -Dfile.encoding=UTF-8 -XX:+UseParallelGC:

-Xmx8g: 8GB heap for Gradle daemon. Suitable for larger projects.
-XX:MaxMetaspaceSize=512m: Metaspace size. Increase if you get OutOfMemoryError: Metaspace.
-Dkotlin.daemon.jvm.options="-Xmx8g": Correctly sets Kotlin daemon memory.
-XX:+HeapDumpOnOutOfMemoryError: Helps in debugging memory issues.
-Dfile.encoding=UTF-8: Good for file encoding.
-XX:+UseParallelGC: Enables parallel garbage collection.

Make sure the Heap memory should be increased based on host system ram range.

Step:4 Uses AndroidX,

android.useAndroidX=true

Step:5 Disables Jetifier.

android.enableJetifier=false: Disables Jetifier. This is good if you've migrated fully to AndroidX. If you still have dependencies using the old support library, this needs to be true (or the line removed, as the default is true).

Step:6 nonTransitiveRClass

android.nonTransitiveRClass=false: This can significantly improve build times, but can also cause runtime errors if not handled carefully.

Step:6 nonFinalResIds

android.nonFinalResIds=false: Prevents non-final resource IDs. Generally, keeping this false is safer, but there are potential performance gains in specific situations if set to true.

See below is your gradle.properties

org.gradle.parallel=true

org.gradle.configuration-cache=true # Enable configuration caching

org.gradle.caching=true # Enable the Gradle build cache

gradle=build -x lint -x lintVitalBasicRelease # Exclude lint for faster dev builds

org.gradle.jvmargs=-Xmx8g -XX:MaxMetaspaceSize=512m -Dkotlin.daemon.jvm.options="-Xmx8g" -XX:+HeapDumpOnOutOfMemoryError -Dfile.encoding=UTF-8 -XX:+UseParallelGC android.useAndroidX=true

android.enableJetifier=false # Or true, depending on your dependencies android.defaults.buildfeatures.buildconfig=true

android.nonTransitiveRClass=true # Enable non-transitive R classes (TEST THOROUGHLY) android.nonFinalResIds=false # Keep false unless you know what you're doing

Show TextView/Text in Center in Compose

noreply@blogger.com (Himanshu) — Sat, 30 Apr 2022 15:01:00 +0530

Here is a simple way to put your View/Text/TextView as a center, Use Box for showing your content as the center inside the view.

Please find below compose function.

Be noted that fontSize Modifier is part of Experimental API, It may change later.

A Reason for AAPT: libpng error: Not a PNG file and Solution

noreply@blogger.com (Himanshu) — Fri, 10 Jun 2016 17:34:00 +0530

If you are facing issue of AAPT: libpng error: Not a PNG file

Error:Execution failed for task ':app:mergeDebugResources'.
> Error: java.lang.RuntimeException: Some file crunching failed, see logs for details

Solution :

Then you need to check your app's all .png file of android project and make sure you have not change any .jpeg to .png format by mistake . Because it might happen that in previous android studio it might working but with update of new android studio 2.2 it will give Error .

Android Studio 2.2 Now support Google Firebase in built setup

noreply@blogger.com (Himanshu) — Thu, 2 Jun 2016 13:42:00 +0530

Hi All ,

Now you can check feature of firebase from android studio menu --> Tools --> Firebase

you can check menu like below screen :

Now click on that you can see below feature and step for each functionality provided by Firebase .

How should I design my Android application? What kind of MVC pattern should I use? What should I use for an event bus?"

noreply@blogger.com (Himanshu) — Tue, 17 May 2016 11:06:00 +0530

Now Here is answer by - Dianne Hackborn

We often see questions from developers that are asking from the Android platform engineers about the kinds of design patterns and architectures they use in their apps.  But the answer, maybe surprisingly, is we often don't have a strong opinion or really an opinion at all.

(Edit to clarify: when I write "we" here I am talking about the Android platform team.  I am not speaking for all of Google or Android developer relations.  There are lots of good suggestions and opinions inside and outside of Google about how to write apps, and I am not intending to dismiss those.)

Should you use MVC?  Or MVP?  Or MVVM?  I have no idea.  Heck, I only know about MVC from school and had to do a Google search to find other options to put here.

This may be surprising, because Android could feel like it has strong opinions on how apps should be written.  With its Java language APIs and fairly high-level concepts, it can look like a typical application framework that is there to say how applications should be doing their work.  But for the most part, it is not.

It is probably better to call the core Android APIs a "system framework."  For the most part, the platform APIs we provide are there to define how an application interacts with the operating system; but for anything going on purely within the app, these APIs are often just not relevant.

That said, the Android APIs can often look different (or higher level) from what one typically expects in an operating system, which may easily lead to confusion about how they should be used.

For an example of this, let's consider how an operating system defines "how to run an app."  In a classic system, this is basically the contract it has with an application about when it should run:

int main(...) {
   // My app goes here!
}

So the operating system starts the app, calls its main() function, and the app goes off and runs and does what it wants until it decides it is done.  And clearly it is not saying anything here about what the app should be doing or how it should be designed within that main function -- it's a pretty pure blank slate.

In Android, however, we explicitly decided we were not going to have a main() function, because we needed to give the platform more control over how an app runs.  In particular, we wanted to build a system where the user never needed to think about starting and stopping apps, but rather the system took care of this for them...  so the system had to have some more information about what is going on inside of each app, and be able to launch apps in various well-defined ways whenever it is needed even if it currently isn't running.

To accomplish this, we decomposed the typical main entry point of an app into a few different types of interactions the system can have with it.  And these are the Activity, BroadcastReceiver, Service, and ContentProvider APIs that Android developers quickly become familiar with.

These classes may look like they are telling you how the internals of your app should work, but they are not!  In fact, they are all about how your app needs to interact with the system (and how the system can coordinate its interaction with other apps).  As long as that interaction with the system happens, we don't really care what goes on inside of the app.

To illustrate, let's briefly look at these different APIs and what they really mean to the Android system.

Activity

This is the entry into an application for interacting with the user.  From the system's perspective, the key interactions it provides with the app are:

• Keep track of what the user currently cares about (what is on screen) to ensure the process hosting that is kept running.
• Know that previously used processes contain things the user may return to (stopped activities), and thus more highly prioritize keeping those processes around.
• Help the application deal with the situation where its process is killed so the user can return to activities with their previous state restored.
• Provide a way for applications to implement user flows between each other, coordinated by the system.  (The most classic example here being share.)

What we don't care about:

Once we have gotten in to this entry-point to your UI, we really don't care how you organize the flow inside.  Make it all one activity with  manual changes to its views, use fragments (a convenience framework we provide) or some other framework, or split it into additional internal activities.  Or do all three as needed.  As long as you are following the high-level contact of activity (it launches in the proper state, and saves/restores in the current state), it doesn't matter to the system.

BroadcastReceiver

This is a mechanism for the system to deliver events to the application that may be outside of a regular user flow.  Most importantly, because this is another well-defined entry into the app, the system can deliver broadcasts to apps even if they aren't currently running.  So, for example, an app can schedule an alarm to post a notification to tell the user about an upcoming event...  and by delivering that alarm to a BroadcastReceiver of the app, there is no need for the app to remain running until the alarm goes off.

What we don't care about:

Dispatching events within an app is an entirely different thing.  Whether you use some event bus framework, implement your own callback system, whatever...  there is no reason to use the system's broadcasting mechanism, since you aren't dispatching events across apps.  (In fact there is good reason not to -- there is a lot of unnecessary overhead and many potential security issues if using a global broadcast mechanism for the internal implementation of an app.)  We do provide the LocalBroadcastManager convenience class that implements a purely in-process intent dispatching system with a similar API to the system's APIs, if you happen to like them.  But again, there is no reason to use that over something else for things going on purely within your app.

Service

A general-purpose entry point for keeping an app running in the background for all kinds of reasons.  There are actually two very distinct semantics services tell the system about how to manage an app:

Started services are simply telling the system to, for some reason, "keep me running until I say I am done."  This could be to sync some data in the background or play music even after the user leaves the app.  Those also represent two different types of started services that modify how the system handles them:

• Music playback is something the user is directly aware of, so the app tells the system this by saying it wants to be foreground with a notification to tell the user about it; in this case the system knows that it should try really hard to keep that service's process running, because the user will be unhappy if it goes away.

• A regular background service is not something the user is directly aware as running, so the system has more freedom in managing its process.  It may allow it to be killed (and then restarting the service sometime later) if it needs RAM for things that are of more immediate concern to the user.

Bound services are running because some other app (or the system) has said that it wants to make use of the service.  This is basically the service providing an API to another process.  The system thus knows there is a dependency between these processes, so if process A is bound to a service in process B, it knows that it needs to keep process B (and its service) running for A.  Further, if process A is something the user cares about, than it also knows to treat process B as something the user also cares about.

Because of their flexibility (for better or worse), services have turned out to be a really useful building block for all kinds of higher-level system concepts.  Live wallpapers, notification listeners, screen savers, input methods, accessibility services, and many other core system features are all built as services that applications implement and the system binds to when they should be running.

What we don't care about:

Android doesn't care about things going on within your app that don't have any impact on how it should manage your process, so there is no reason to use services in these cases.  For example, if you want to start some background operation to download data for your UI, you should not use a service for this -- it is actually important to not be telling the system to keep your process running while doing this, because it really doesn't need to be and the system would be better off having more freedom in managing it with other things the user is doing.

If you just make a simple background thread (or whatever non-service mechanism you want) to do the downloading, you will get the semantics you want: while the user is in your UI, the system will keep your process running for that, so the download will never be interrupted.  When they leave your UI, your process will still be kept around (cached) and able to continue downloading, as long as its RAM isn't needed elsewhere.

Likewise for connecting different parts of your app together, there is no reason to bind to a service that is running in the same process as the one binding to it.  Doing so is not actively harmful -- the system just sees a dependency from the process to itself so doesn't try to keep it around any more than usual -- but it is a bunch of unnecessary work for both you and the system.  Instead, you can just use singletons or other normal in-process patterns for connecting pieces of your app together.

ContentProvider

Finally, the ContentProvider is a fairly specialized facility for publishing data from an app to other places.  People generally think of them as an abstraction on a database, because there is a lot of API and support built in to them for that common case...  but from the system design perspective, that isn't their point.

What these are to the system is an entry-point into an app for publishing named data items, identified by a URI scheme.  Thus an app can decide how it wants to map the data it contains to a URI namespace, handing out those URIs to other entities which can in turn use them to access the data.  There are a few particular things this allows the system to do in managing an app:

• Handing out a URI doesn't require the app remain running, so these can go all over the place with the owning app being dead.  Only at the point where someone tells the system, "hey give me the data for this URI" does it need to make sure the app owning that data is running, so it can ask the app to retrieve and return the data.

• These URIs also provide an important fine-grained security model.  For example, an application can place the URI for an image it has on the clipboard, but leave its content provider locked up so nobody can freely access it.  When another app pulls that URI off the clipboard, the system can give it a temporary "URI permission grant" so that it is allowed to access the data only behind that URI, but nothing else in the app.

What we don't care about:

It doesn't really matter how you implement the data management behind a content provider; if you don't need structured data in a SQLite database, don't use SQLite.  For example, the FileProvider helper class is an easy way to make raw files in your app available through a content provider.

Also, if you are not publishing data from your app for others to use, there is no need to use a content provider at all.  It is true, because of the various helpers built around content providers, this can be an easy way to put data in a SQLite database and use it to populate UI elements like a ListView.  But if any of this stuff makes what you are trying to do more difficult, then feel free to not use it and instead use a more appropriate data model for your app.﻿

SOURCE ->> https://plus.google.com/105051985738280261832/posts/FXCCYxepsDU

9,613 followers -

Google (Android Framework)

ABOUT

FRIENDS

andorid material design with design support library

noreply@blogger.com (Himanshu) — Tue, 7 Jul 2015 18:32:00 +0530

Android design support library give us many material design components that are support from android 2.1 and higher devices.

I am using android studio for creating app using design support library so if you don't have android studio then get it from Download studio.

Below are new components provided by design support lib.

You must take care below thing while you want your view to be support from andorid 2.1 and above .

android.support.design.widget.*

In stead of * your view will come.

AppBarLayout is a vertical LinearLayout which implements many of the features of material designs app bar concept, namely scrolling gestures.

Children should provide their desired scrolling behavior through setScrollFlags(int) and the associated layout xml attribute: app:layout_scrollFlags.

This view depends heavily on being used as a direct child within a CoordinatorLayout. If you use AppBarLayout within a different ViewGroup, most of it's functionality will not work.

AppBarLayout also requires a separate scrolling sibling in order to know when to scroll. The binding is done through the AppBarLayout.ScrollingViewBehavior behavior class, meaning that you should set your scrolling view's behavior to be an instance of AppBarLayout.ScrollingViewBehavior. A string resource containing the full class name is available.

 


 
    
 

 

 
    
 
    
 

 



You can see google guide for using AppBarLayout  from Google Design Spec AppBar and example use in my app at github.

CollapsingToolbarLayout is a wrapper for Toolbar which implements a collapsing app bar. It is designed to be used as a direct child of a AppBarLayout. CollapsingToolbarLayout contains the following features:

CollpasingToolbarLayout is use full when you want your top header content to be collapse from RecycleView or  NestedScrollView .

NOTE: Scrolling Technique will not work with Listview use RecycleView or NestedScrollView instead of it.

FloatingActionButton :

You can see in top image where i have use floating button over RecycleView and below is xml layout that used for it.

 

 
 
    
 
    
 
        
 
 
        
 
        
 
         
 
 
 
    
 
 
    
 
 

 

 

 
 

It will give design output like below one



NavigationView

Represents a standard navigation menu for application. The menu contents can be populated by a menu resource file.

NavigationView is typically placed inside a DrawerLayout.

 
    
 
        
 
 
        
 
        
        
 
    
 
 
    
 
 



It will look like below screen :



TabLayout

We need to put Tablayout inside AppBarLayout like below :


 
            
 
 
            
 
            
 
             
 
 
 
        



Then in java code you can add Tabs
mTabLayout=(TabLayout)findViewById(com.himotech.matrialdesign.R.id.tab_layout);

/*mTabLayout.addTab(mTabLayout.newTab().setCustomView(R.layout.custom_tab_layout));
 
mTabLayout.addTab(mTabLayout.newTab().setCustomView(R.layout.custom_tab_layout));
 
mTabLayout.addTab(mTabLayout.newTab().setCustomView(R.layout.custom_tab_layout));*/
 
mTabLayout.addTab(mTabLayout.newTab().setText("Tab One"));
 
mTabLayout.addTab(mTabLayout.newTab().setText("Tab Two"));
 
mTabLayout.addTab(mTabLayout.newTab().setText("Tab Third"));




You can check exiting project from Github

Material design with use of android design support library

noreply@blogger.com (Himanshu) — Fri, 12 Jun 2015 17:02:00 +0530

Google recently on 25 May 2015 post update in support library which have few major components which are useful for creating app which look like more materials .

You can check this official blog http://android-developers.blogspot.in/2015/05/android-design-support-library.html.

From that i have created a demo that showing uses of this library .

You can find it on https://github.com/Himanshu4003/MaterialDesign

Demo App of android in Api call ,andorid database example and xml parsing

noreply@blogger.com (Himanshu) — Sat, 21 Feb 2015 12:26:00 +0530

Here are few demo example that i have created in past .

This is for api call of Get and get response :

https://drive.google.com/file/d/0B-8An4Rd1nmKQlNCSTVvTmJBU3M/view?usp=sharing

Load Bitmap in android :

https://drive.google.com/file/d/0B-8An4Rd1nmKZWNmNzM5NDEtZDgwMy00YzY3LTgyMWYtYjk0MjAzNzE2NGEx/view?usp=sharing

Working with database :

https://drive.google.com/file/d/0B-8An4Rd1nmKS2RGelh0MjBjb3djVGhQcXpCalJvUDl2eEVB/view?usp=sharing

XML parsing in android :
https://drive.google.com/file/d/0B-8An4Rd1nmKNzNjNTY3YzktYzZmZi00ZjVhLTgyZWQtN2E4NTE2NDFiYWVi/view?usp=sharing

Gridview image in android:

https://drive.google.com/file/d/0B-8An4Rd1nmKZDllZmNlMTUtMGM4ZS00ZGI1LTljNjMtNzdlNTFiNjg1ODM3/view?usp=sharing

Creating notification using Notification Compact and Extended notification

noreply@blogger.com (Himanshu) — Thu, 18 Dec 2014 19:55:00 +0530

Today i have use extended notification style and check how it's working .

if you want to try check below activity .

public class NotificationActivity extends ActionBarActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_notification);

        initView();
    }

    private void initView(){

        Log.v("LOG_TAG","NotificationActivity-->"+ "initView(0)");

        Button mbtnGeneNotification = (Button) findViewById(R.id.btn_notification);

        Button mbtnExtendedNotification=(Button)findViewById(R.id.btn_extended);

        mbtnExtendedNotification.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                generateExtendedNotification();
            }
        });
        mbtnGeneNotification.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {

                generateSimpleNotification();

            }
        });

    }

    private void generateSimpleNotification(){

        NotificationCompat.Builder mNotificationBuilder=new NotificationCompat.Builder(this);

        mNotificationBuilder.setSmallIcon(R.drawable.ic_launcher);

        mNotificationBuilder.setContentText("App notification text here");

        mNotificationBuilder.setContentTitle("App notification Title here");

        mNotificationBuilder.setAutoCancel(true);

        // Creates an explicit intent for an Activity in your app

        Intent resultIntent=new Intent(this,NotificationParentActivity.class);

         // The stack builder object will contain an artificial back stack for the
        // started Activity.
        // This ensures that navigating backward from the Activity leads out of
        // your application to the Home screen.
        TaskStackBuilder mStackBuilder=TaskStackBuilder.create(this);
        // Adds the back stack for the Intent (but not the Intent itself)
        mStackBuilder.addParentStack(NotificationParentActivity.class);
        // Adds the Intent that starts the Activity to the top of the stack
        mStackBuilder.addNextIntent(resultIntent);
        PendingIntent mPendingIntent=mStackBuilder.getPendingIntent(0,PendingIntent.FLAG_UPDATE_CURRENT);

        mNotificationBuilder.setContentIntent(mPendingIntent);

        NotificationManager mNotificationManager =
                (NotificationManager) getSystemService(
                        Context.NOTIFICATION_SERVICE);
// mId allows you to update the notification later on.
        mNotificationManager.notify(0, mNotificationBuilder.build());

    }

    private void generateSimplenNonStackNotification(){

        NotificationCompat.Builder mNotificationBuilder=new NotificationCompat.Builder(this);

        mNotificationBuilder.setSmallIcon(R.drawable.ic_launcher);

        mNotificationBuilder.setContentText("App notification text here");

        mNotificationBuilder.setContentTitle("App notification Title here");

        mNotificationBuilder.setAutoCancel(true);

        // Creates an explicit intent for an Activity in your app

        Intent resultIntent=new Intent(this,NotificationActivity.class);

        // The stack builder object will contain an artificial back stack for the
        // started Activity.
        // This ensures that navigating backward from the Activity leads out of
        // your application to the Home screen.

        // Sets the Activity to start in a new, empty task
        resultIntent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK | Intent.FLAG_ACTIVITY_CLEAR_TASK);

        PendingIntent mPendingIntent= PendingIntent.getActivity(this,1,resultIntent,PendingIntent.FLAG_UPDATE_CURRENT);

         //mStackBuilder.getPendingIntent(0,PendingIntent.FLAG_UPDATE_CURRENT);

        mNotificationBuilder.setContentIntent(mPendingIntent);

        NotificationManager mNotificationManager =
                (NotificationManager) getSystemService(
                        Context.NOTIFICATION_SERVICE);
// mId allows you to update the notification later on.
        mNotificationManager.notify(0, mNotificationBuilder.build());

    }

    private void generateExtendedNotification(){

        NotificationCompat.Builder mBuilder = new NotificationCompat.Builder(this)
                .setSmallIcon(R.drawable.ic_launcher)
                .setContentTitle("Event tracker")
                .setContentText("Events received");

        NotificationCompat.InboxStyle inboxStyle =
                new NotificationCompat.InboxStyle();

        mBuilder.setAutoCancel(true);

        mBuilder.setNumber(4);

        String[] events = new String[6];

        events[0]="It's Holiday today";
        events[1]="It's Saturday today";
        events[2]="It's Sunday today";
        events[3]="It's Monday today";
        events[4]="It's Tueday today";

// Sets a title for the Inbox in expanded layout
        inboxStyle.setBigContentTitle("Event tracker details:");

        // Moves events into the expanded layout
        for (int i=0; i < events.length; i++) {

            inboxStyle.addLine(events[i]);
        }
// Moves the expanded layout object into the notification object.
        mBuilder.setStyle(inboxStyle);

        Intent resultIntent=new Intent(this,NotificationParentActivity.class);

        // The stack builder object will contain an artificial back stack for the
        // started Activity.
        // This ensures that navigating backward from the Activity leads out of
        // your application to the Home screen.

        // Sets the Activity to start in a new, empty task
        resultIntent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK | Intent.FLAG_ACTIVITY_CLEAR_TASK);

        PendingIntent mPendingIntent= PendingIntent.getActivity(this,2,resultIntent,PendingIntent.FLAG_UPDATE_CURRENT);

        //mStackBuilder.getPendingIntent(0,PendingIntent.FLAG_UPDATE_CURRENT);

        mBuilder.setContentIntent(mPendingIntent);

        NotificationManager mNotificationManager =
                (NotificationManager) getSystemService(
                        Context.NOTIFICATION_SERVICE);
// mId allows you to update the notification later on.
        mNotificationManager.notify(2, mBuilder.build());

    }

    @Override
    protected void onNewIntent(Intent intent) {

        Log.i("LOG_TAG","onNewIntent------>");

        super.onNewIntent(intent);
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.menu_notification, menu);
        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        // Handle action bar item clicks here. The action bar will
        // automatically handle clicks on the Home/Up button, so long
        // as you specify a parent activity in AndroidManifest.xml.
        int id = item.getItemId();

        //noinspection SimplifiableIfStatement
        if (id == R.id.action_settings) {
            return true;
        }

        return super.onOptionsItemSelected(item);
    }
}

Below is my manifest file:

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.himosoft.notificationtype" >

    <application
        android:allowBackup="true"
        android:icon="@drawable/ic_launcher"
        android:label="@string/app_name"
        android:theme="@style/AppTheme" >
        <activity
            android:name=".NotificationActivity"
            android:label="@string/app_name" >
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>

        <activity
            android:name=".NotificationParentActivity"
            android:label="@string/title_activity_notification_parent"
            android:parentActivityName=".NotificationActivity"
            >

            <meta-data
                android:name="android.support.PARENT_ACTIVITY"
                android:value=".NotificationActivity"
                >

            </meta-data>
        </activity>

    </application>

</manifest>

Android L like Drawer navigation animation and it's using Toolbar for top Navigation

noreply@blogger.com (Himanshu) — Wed, 17 Dec 2014 18:19:00 +0530

I have created one demo app from Sliding tab demo with android L like animation of arrow.

you can check my git for complete code and comment over there is you have any issue .I have build that project using android studio so you need to have it for run and test.

https://github.com/Himanshu4003/SlidingDrawerWithTabs

Here is look of app screen:

Happy Coding

Let ' s check android L ' s new UI RecyclerView

noreply@blogger.com (Himanshu) — Fri, 22 Aug 2014 23:32:00 +0530

As per Google Document RecyclerView is a more advanced and flexible version of ListView.

This widget is a container for large sets of views that can be recycled and scrolled very efficiently. Use the RecyclerView widget when you have lists with elements that change dynamically.

The RecyclerView has been developed with extensibility in mind, so it is possible to create any kind of layout you can think of, but not without a little pain-in-the-ass dose. This is Android, so things are never easy.

If you want to use a RecyclerView, you will need to feel comfortable with three elements:

- RecyclerView.Adapter
- LayoutManager
- ItemAnimator

A layout manager for positioning items

Default animations for common item operations

RecyclerView is easy to use, because it provides:

You also have the flexibility to define custom layout managers and animations for this widget.

To use the RecyclerView widget, you have to specify an adapter and a layout manager. To create an adapter, you extend the RecyclerView.Adapter class. The details of the implementation depend on the specifics of your dataset and the type of views. For more information, see the examples below.

We can use RecyclerView from Api version 7 in android .

Let me make my first list with RecyclerView and share my code with you all.

Below is my Activity class which use RecycleView to show list items.

import java.util.ArrayList;

import android.support.v7.app.ActionBarActivity;
import android.support.v7.widget.LinearLayoutManager;
import android.support.v7.widget.RecyclerView;
import android.support.v7.widget.RecyclerView.LayoutManager;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;

public class RecycleActivity extends ActionBarActivity {


    private RecyclerView mRecyclerView;

    private ListAdapter mListAdapter;


    private ArrayList<String> mArrayList=new ArrayList<String>();


    private LayoutManager mLayoutManager;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
       super.onCreate(savedInstanceState);
       setContentView(R.layout.activity_recycle);

       initView();

    }


    private void initView(){

       mRecyclerView=(RecyclerView)findViewById(R.id.recycle_view);

       mRecyclerView.setHasFixedSize(true);

       mLayoutManager=new LinearLayoutManager(this);

       mRecyclerView.setLayoutManager(mLayoutManager);

       mArrayList.clear();

       for (int i=0;i<30;i++){

           mArrayList.add("Listview Item at Position "+ i);

       }


       mListAdapter=new ListAdapter(mArrayList);

       mRecyclerView.setAdapter(mListAdapter);


    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
       // Inflate the menu; this adds items to the action bar if it is present.
       getMenuInflater().inflate(R.menu.recycle, menu);
       return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
       // Handle action bar item clicks here. The action bar will
       // automatically handle clicks on the Home/Up button, so long
       // as you specify a parent activity in AndroidManifest.xml.
       int id = item.getItemId();
       if (id == R.id.action_settings) {
           return true;
       }
       return super.onOptionsItemSelected(item);
    }
}

Here is my Adapter Class to bind data in to RecycleView

import java.util.ArrayList;
import android.support.v7.widget.RecyclerView;
import android.support.v7.widget.RecyclerView.ViewHolder;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.CheckBox;
import android.widget.CompoundButton;
import android.widget.CompoundButton.OnCheckedChangeListener;
import android.widget.ImageView;
import android.widget.RelativeLayout;
import android.widget.TextView;

public class ListAdapter extends RecyclerView.Adapter<ViewHolder>{

    private ArrayList<String> mArrayData;


    public ListAdapter(ArrayList<String> mArrayListUpdate){

        this.mArrayData=mArrayListUpdate;

    }

    public static class ViewHolder extends android.support.v7.widget.RecyclerView.ViewHolder{

        public ViewHolder(View view) {
            super(view);
            // TODO Auto-generated constructor stub

            mRlRowView=(RelativeLayout) view;

            mTxtView=(TextView) mRlRowView.findViewById(R.id.txt_title);

            mImgView=(ImageView)mRlRowView.findViewById(R.id.img_row);

            mCheckBox=(CheckBox)mRlRowView.findViewById(R.id.checkbox_item);

        }

        CheckBox mCheckBox;

        ImageView mImgView;

        TextView mTxtView;

        RelativeLayout mRlRowView;
    }

    @Override
    public int getItemCount() {
        // TODO Auto-generated method stub
        return mArrayData.size();

    }


    // Replace the contents of a view (invoked by the layout manager)
    @Override
    public void onBindViewHolder(
            android.support.v7.widget.RecyclerView.ViewHolder viewHolder, final int position) {
        // TODO Auto-generated method stub

        Log.i("LOG_TAG", "onBindViewHolder-->"+ position);

        ViewHolder mViewHolder=((ViewHolder)viewHolder);

        mViewHolder.mTxtView.setText(mArrayData.get(position));

        mViewHolder.mCheckBox.setOnCheckedChangeListener(new OnCheckedChangeListener() {

            @Override
            public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
                // TODO Auto-generated method stub

                Log.w("LOG_TAG", "onCheckedChanged is"+ isChecked + "Position is"+ position);

            }
        });

    }

    @Override
    public android.support.v7.widget.RecyclerView.ViewHolder onCreateViewHolder(
            ViewGroup viewGroup, int viewType) {
        // TODO Auto-generated method stub
        // create a new view

        Log.i("LOG_TAG", "onCreateViewHolder-->");
        View mView=LayoutInflater.from(viewGroup.getContext()).inflate(R.layout.list_row_item, viewGroup, false);

        // set the view's size, margins, paddings and layout parameters

        ViewHolder mViewHolder=new ViewHolder(mView);


        return mViewHolder;
    }
   }

Here is download link for my created Demo :
https://drive.google.com/file/d/0B-8An4Rd1nmKcU93VHU1Y1FWTG8/view?usp=sharing
It's Goog Drive link and from top there is download icons from there you can easily download whole code.

What mean by Activities, tasks, and intents in Android ?

noreply@blogger.com (Himanshu) — Fri, 16 May 2014 12:56:00 +0530

Activities In Android:

In Android, an activity is an application component that defines a screen of information and all of the associated actions the user can perform. Your app is a collection of activities, consisting of both the activities you create and those you re-use from other apps.

Tasks:

A task is the sequence of activities a user follows to accomplish a goal. A single task can make use of activities from just one app, or may draw on activities from a number of different apps.

Intents:

An intent is a mechanism for one app to signal it would like another app's assistance in performing an action. An app's activities can indicate which intents they can respond to. For common intents such as "Share", the user may have many apps installed that can fulfill that request.

Custom Alert Or Custom Dialog Fragment in Android

noreply@blogger.com (Himanshu) — Thu, 17 Apr 2014 16:16:00 +0530

I recently can not able to Create Alert Dialog with out it Boarder so i end up to resolved it by Support Dialog Fragment .

You can check my code .

public class AlertActivity extends ActionBarActivity {

    private AlertDialog mAlertDialog;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_alert);

        if (savedInstanceState == null) {
            getSupportFragmentManager().beginTransaction()
                    .add(R.id.container, new PlaceholderFragment()).commit();
        }
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {

        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.alert, menu);
        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        // Handle action bar item clicks here. The action bar will
        // automatically handle clicks on the Home/Up button, so long
        // as you specify a parent activity in AndroidManifest.xml.
        int id = item.getItemId();
        if (id == R.id.action_settings) {

            //showAlertDialog();

            CreateDialogFragment();

            return true;
        }
        return super.onOptionsItemSelected(item);
    }

    /**
    * A placeholder fragment containing a simple view.
    */
    public static class PlaceholderFragment extends Fragment {

        public PlaceholderFragment() {

        }

        @Override
        public View onCreateView(LayoutInflater inflater, ViewGroup container,
                Bundle savedInstanceState) {
            View rootView = inflater.inflate(R.layout.fragment_alert,
                    container, false);
            return rootView;
        }
    }

    private void showAlertDialog() {

        AlertDialog.Builder mBuilder = new Builder(new ContextThemeWrapper(
                this, android.R.style.Theme_Translucent_NoTitleBar));// new
                                                                        // Builder(this,android.R.style.Theme_Translucent_NoTitleBar);

        View mView = LayoutInflater.from(this).inflate(
                R.layout.alert_dialog_layout, null);

        mBuilder.setView(mView);
        // mBuilder.setC
        // mBuilder.s

        mAlertDialog = mBuilder.create();

        mAlertDialog.setInverseBackgroundForced(true);
        mAlertDialog.setCanceledOnTouchOutside(true);

        mAlertDialog.getWindow().setBackgroundDrawableResource(
                android.R.color.transparent);
        mAlertDialog.show();

    }

    private void CreateDialogFragment() {

        View mView = LayoutInflater.from(this).inflate(
                R.layout.alert_dialog_layout, null);
        MyDialogFragment mDialogFragment=new MyDialogFragment(mView);

        //mDialogFragment.setStyle(MyDialogFragment.STYLE_NO_FRAME, android.R.style.Theme_Translucent_NoTitleBar);
        mDialogFragment.setShowsDialog(true);


        mDialogFragment.show(getSupportFragmentManager(), "dialog");

    }

    public class MyDialogFragment extends DialogFragment {

        private View mView;

        /*
        * public MyDialogFragment newInstance(View mView) {
        *
        * mView=mView; return new MyDialogFragment(); }
        */

        public MyDialogFragment(View mView) {
            this.mView = mView;
        }

        @Override
        public View onCreateView(LayoutInflater inflater, ViewGroup container,
                Bundle savedInstanceState) {

            return mView;
        }

        @Override
        public Dialog onCreateDialog(Bundle savedInstanceState) {
        Dialog dialog = super.onCreateDialog(savedInstanceState);

        // request a window without the title
        dialog.getWindow().requestFeature(Window.FEATURE_NO_TITLE);
        return dialog;
        }
    }

}

Designing And Implementing Android UI For Phones and Tablets

noreply@blogger.com (Himanshu) — Thu, 27 Mar 2014 12:26:00 +0530

I have found one of Google IO pdf document which give us some fundamental guide for making android UI design for Phone and Tables.

Please have look on pdf from below link.

http://goo.gl/QJFCTG

How to show PopupWindow in android with background transparent when it show

noreply@blogger.com (Himanshu) — Tue, 11 Mar 2014 13:51:00 +0530

In this tutorial we will make android popup which will show as drop-down window at particular view point.

Below is Activity class which use to make Popup window on button click.

public class PoupWindowActivity extends Activity implements OnClickListener{

 

 

 public Button mBtnPopUpWindow;

 

 private PopupWindow mPopupWindow;

 

 private Button mBtnCancel;

 

 @Override

 protected void onCreate(Bundle savedInstanceState) {

  // TODO Auto-generated method stub

  super.onCreate(savedInstanceState);

  

  setContentView(R.layout.main_screen_layout);

  

  initView();

 }



 

 

 private void initView(){

  

  mBtnPopUpWindow=(Button)findViewById(R.id.btn_popup);

  mBtnPopUpWindow.setOnClickListener(this);

  

  

 }







 @Override

 public void onClick(View v) {

  

  switch(v.getId()){

  

  

  case R.id.btn_popup:

   

   showPopupWindow();

   

   break;

   

  case R.id.btn_cancel:

   

   

   if(mPopupWindow!=null & mPopupWindow.isShowing()){

    mPopupWindow.dismiss();

    mPopupWindow=null;

   }

   break;

  }

 }

 

 

 private void showPopupWindow(){

  

  LayoutInflater mLayoutInflater=LayoutInflater.from(this);

  View mView=mLayoutInflater.inflate(R.layout.pop_up_layout, null);

  mPopupWindow=new PopupWindow(mView, LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT, true);

 // mPopupWindow=new PopupWindow(mView,,LayoutParams.WRAP_CONTENT);

  mPopupWindow.setContentView(mView);

  mBtnCancel=(Button) mView.findViewById(R.id.btn_cancel);

  mBtnCancel.setOnClickListener(this);

  Drawable d = new ColorDrawable(Color.WHITE);

        d.setAlpha(130);

      

  mPopupWindow.setBackgroundDrawable(new BitmapDrawable());

  

  mPopupWindow.showAsDropDown(mBtnPopUpWindow, 0, 0,Gravity.LEFT);

  getWindow().setBackgroundDrawable(d);

  mPopupWindow.setOnDismissListener(new OnDismissListener() {

   

   @Override

   public void onDismiss() {

    

    Drawable d = new ColorDrawable(Color.WHITE);

    

    getWindow().setBackgroundDrawable(d);

   }

  });

 }

 



}

Here are xml file use for Activity and Popup window layout.

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >

<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:gravity="right"
android:orientation="horizontal" >

<Button

style="?android:attr/buttonStyleSmall"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:text="@string/popupwindow"
android:id="@+id/btn_popup"
/>
</LinearLayout>

</LinearLayout>

Popup window xml:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical"
android:paddingLeft="10dp"
android:paddingRight="10dp" >

<RelativeLayout
android:layout_width="match_parent"
android:layout_height="wrap_content" >

<ImageView
android:id="@+id/img_popup_arrow"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentRight="true"
android:layout_alignParentTop="true"
android:layout_marginRight="30dp"
android:scaleType="fitXY"
android:src="@drawable/ic_alerts_and_states_warning" />

<LinearLayout
android:layout_width="match_parent"
android:layout_height="20dp"
android:layout_below="@+id/img_popup_arrow"
android:background="@drawable/bg_orange_round" >
</LinearLayout>
</RelativeLayout>

<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="@drawable/bg_white_round"
android:orientation="vertical" >

<EditText
android:id="@+id/editxt_search"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:ems="10"
android:inputType="textPersonName" >

<requestFocus />
</EditText>

<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:gravity="right" >

<Button
android:id="@+id/btn_search"
style="?android:attr/buttonStyleSmall"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="@string/search" />

<Button
android:id="@+id/btn_cancel"
style="?android:attr/buttonStyleSmall"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="right|center_vertical"
android:text="@string/cancel" />
</LinearLayout>
</LinearLayout>

</LinearLayout>

Here is output of our popup window:

You can download source code from my drive as well:

https://drive.google.com/file/d/0B-8An4Rd1nmKeVJSejlEYUxwRGc/edit?usp=sharing

Android : Custom Listview with EditText in it and Managing data of Editext

noreply@blogger.com (Himanshu) — Thu, 6 Feb 2014 14:53:00 +0530

In One of my application we required to have EditText in Listview and i need to manage hot to fetch data from particular Editext when user done Editing after Using TextWatcher interface i can able to do what i required .

So I am sharing my code with you people ,if any one have better approach to work with Edittext in Listview and manage it's data as well then you can share your idear and implementation as well.

As my screen contain only list so i prefer to use List Activity.

public class ListActivity extends android.app.ListActivity {
private ListView mListview;
private final int TOTAL_ITEMS=100; 
private BaseListAdapter mBaseListAdapter;
ArrayList<String> mArrayList=new ArrayList<String>(TOTAL_ITEMS);
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
//setContentView(R.layout.activity_list);
init();
}
private void init(){
mListview=getListView();
for(int i=0;i<TOTAL_ITEMS;i++){
mArrayList.add("");
}
mBaseListAdapter=new BaseListAdapter(ListActivity.this, mArrayList);
mListview.setAdapter(mBaseListAdapter);
}

@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.list, menu);
return true;
}

}


Other class required is my Listview adapter class which is below .

public class BaseListAdapter extends BaseAdapter implements OnTouchListener,TextWatcher{
private Context mContext;
private ArrayList<String> mArrayEdittxt;
private LayoutInflater mLayoutInflater;
private int mPosition;
private boolean isTouch=false;
public BaseListAdapter(Context _Context,ArrayList<String> mArrayEditTxtData){
this.mContext=_Context;
mArrayEdittxt=mArrayEditTxtData;
mLayoutInflater=(LayoutInflater) mContext.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
}

@Override
public int getCount() {
// TODO Auto-generated method stub
return mArrayEdittxt.size();
}

@Override
public Object getItem(int position) {
// TODO Auto-generated method stub
return position;
}

@Override
public long getItemId(int position) {
// TODO Auto-generated method stub
return position;
}

@Override
public View getView(int position, View convertView, ViewGroup parent) {
ViewHolder mViewHolder;
if(convertView==null){
mViewHolder=new ViewHolder();
convertView=mLayoutInflater.inflate(R.layout.list_row_items, parent, false);
mViewHolder.mEditxt=(EditText)convertView.findViewById(R.id.editxt);
mViewHolder.mImgView=(ImageView)convertView.findViewById(R.id.imgview);
convertView.setTag(mViewHolder);
}else{
mViewHolder=(ViewHolder) convertView.getTag();
}
isTouch=false;
mViewHolder.mEditxt.addTextChangedListener(BaseListAdapter.this);
mViewHolder.mEditxt.setOnTouchListener(BaseListAdapter.this);
mViewHolder.mEditxt.setTag(position);
mViewHolder.mEditxt.setText(mArrayEdittxt.get(position));
return convertView;
}
public class ViewHolder{
EditText mEditxt;
ImageView mImgView;
}


@Override
public boolean onTouch(View v, MotionEvent event) {
Log.v("LOG_TAG", "onTouch-->");
isTouch=true;
mPosition=(Integer) v.getTag();
return false;
}



@Override
public void afterTextChanged(Editable s) {
Log.v("LOG_TAG", "afterTextChanged -->"+ s.toString() );
if(isTouch){
mArrayEdittxt.set(mPosition, s.toString());
}
}



@Override
public void beforeTextChanged(CharSequence s, int start, int count,
int after) {
}



@Override
public void onTextChanged(CharSequence s, int start, int before, int count) {
}

}


Below is my listview row xml file .

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="wrap_content" >

    <EditText
        android:id="@+id/editxt"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentLeft="true"
        android:layout_centerVertical="true"
        android:layout_marginLeft="5dp"
        android:layout_marginRight="5dp"
        android:layout_toLeftOf="@+id/imgview"
        android:ems="10" >

        <requestFocus />
        
    </EditText>

    <ImageView
        android:id="@+id/imgview"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentRight="true"
        android:layout_centerVertical="true"
        android:src="@android:drawable/ic_media_play" />

</RelativeLayout>

If any one want to check my source code they can directly download it from my Google Drive -->
https://drive.google.com/file/d/0B-8An4Rd1nmKNXNDTDRqM2FxWFU/edit?usp=sharing

Face Detection example in andoid from Gallery and by Camera capure image

noreply@blogger.com (Himanshu) — Wed, 18 Sep 2013 22:04:00 +0530

Hello Every one ,

I recently learn face detection in android by searching in google and other blogger i found below code and i have made some change in it .

Hope you will like my code and also shared your information in image processing and your expose in face detection in android.

Below is my android Activity code :

public class FaceDetectActivity extends Activity  implements OnClickListener{



        private static final int TAKE_PICTURE_CODE = 100;

        private static final int MAX_FACES = 5;

         

        private static final int SELECT_PICTURE = 6;

        

        private Bitmap cameraBitmap = null;

        private Button btn_TakePhoto;

        

        private Button btn_select_image;

        

        private Button btn_facedetect;

         

        private ImageView imageView;

        

        private int mWidth;

        private int mHeight;

        

        private ProgressDialog mProgressDialog;

        

        private Button btn_select_img;

        

       

    protected void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);

        setContentView(R.layout.activity_face_detect);

        

        initDisplay();

        

        btn_TakePhoto=(Button)findViewById(R.id.take_picture);

        btn_TakePhoto.setOnClickListener(this);

        btn_select_img=(Button)findViewById(R.id.btn_select_gallary);

        btn_select_img.setOnClickListener(this);

        

        

        

    }





    

    

    private void initDisplay(){

        

        DisplayMetrics metrics = new DisplayMetrics();

        getWindowManager().getDefaultDisplay().getMetrics(metrics);



        mHeight=metrics.heightPixels;

        mWidth=metrics.widthPixels;

        

        Log.v("LOG_TAG", "Wdith is "+ mWidth +"Height is "+ mHeight);

    }

    

    

    @Override

    public boolean onCreateOptionsMenu(Menu menu) {

        // Inflate the menu; this adds items to the action bar if it is present.

        getMenuInflater().inflate(R.menu.face_detect, menu);

        return true;

    }



    

    

    private void openCamera(){

        Intent intent = new Intent(android.provider.MediaStore.ACTION_IMAGE_CAPTURE);

         

        startActivityForResult(intent, TAKE_PICTURE_CODE);

    }

     

    private void processCameraImage(Intent intent){

        setContentView(R.layout.face_detect_layout);

         

        btn_facedetect=(Button)findViewById(R.id.detect_face);

        btn_facedetect.setOnClickListener(this);

         

        

        

        btn_select_image=(Button)findViewById(R.id.btn_pickimag);

        

        btn_select_image.setOnClickListener(this);

        

        

        imageView= (ImageView)findViewById(R.id.image_view);

         

        cameraBitmap = (Bitmap)intent.getExtras().get("data");

         

        imageView.setImageBitmap(cameraBitmap);

    }



    @Override

    public void onClick(View v) {

        

        switch(v.getId()){

        

        case R.id.take_picture:

            

            openCamera();

            break;

            

        case R.id.detect_face:

            

            //detectFaces();

            

            new FaceDetectAsyncTask().execute(cameraBitmap);

            

            break;

            

        case R.id.btn_pickimag:

            

            startImagePicker();

            

            break;

        

            

        case R.id.btn_select_gallary:

            

            startImagePicker();

            

            break;

        

        }

        

    }

    

    

    

    private Object[] detectFaces(Bitmap mBitmap){

       

        Object[] mObject = new Object[2];

        

        if(null != mBitmap){

                

               int width = mBitmap.getWidth();

                int height = mBitmap.getHeight();

                 

                FaceDetector detector = new FaceDetector(width, height,FaceDetectActivity.MAX_FACES);

                Face[] faces = new Face[FaceDetectActivity.MAX_FACES];

                 

                Bitmap bitmap565 = Bitmap.createBitmap(width, height, Config.RGB_565);

                Paint ditherPaint = new Paint();

                Paint drawPaint = new Paint();

                 

                ditherPaint.setDither(true);

                drawPaint.setColor(Color.GREEN);

                drawPaint.setStyle(Paint.Style.STROKE);

                drawPaint.setStrokeWidth(2);

                 

                Canvas canvas = new Canvas();

                canvas.setBitmap(bitmap565);

                canvas.drawBitmap(mBitmap, 0, 0, ditherPaint);

                 

                int facesFound = detector.findFaces(bitmap565, faces);

                PointF midPoint = new PointF();

                float eyeDistance = 0.0f;

                float confidence = 0.0f;

                 

                Log.i("FaceDetector", "Number of faces found: " + facesFound);

                 

                if(facesFound > 0)

                {

                        for(int index=0; index<facesFound; ++index){

                                faces[index].getMidPoint(midPoint);

                                eyeDistance = faces[index].eyesDistance();

                                confidence = faces[index].confidence();

                                 

                                Log.i("FaceDetector",

                                                "Confidence: " + confidence +

                                                ", Eye distance: " + eyeDistance +

                                                ", Mid Point: (" + midPoint.x + ", " + midPoint.y + ")");

                                 

                                canvas.drawRect((int)midPoint.x - eyeDistance ,

                                                                (int)midPoint.y - eyeDistance ,

                                                                (int)midPoint.x + eyeDistance,

                                                                (int)midPoint.y + eyeDistance, drawPaint);

                        }

                }else{

                    //Toast.makeText(this, "No Face Detect", Toast.LENGTH_SHORT).show();

                }

                 

                /*String filepath = Environment.getExternalStorageDirectory() + "/facedetect" + System.currentTimeMillis() + ".jpg";

                 

                        try {

                                FileOutputStream fos = new FileOutputStream(filepath);

                                 

                                bitmap565.compress(CompressFormat.JPEG, 90, fos);

                                 

                                fos.flush();

                                fos.close();

                        } catch (FileNotFoundException e) {

                                e.printStackTrace();

                        } catch (IOException e) {

                                e.printStackTrace();

                        }*/

                         

                       /* ImageView imageView = (ImageView)findViewById(R.id.image_view);

                         

                        imageView.setImageBitmap(bitmap565);*/

                

                mObject[0]=facesFound;

                mObject[1]=bitmap565;

                

                        return mObject;

        }

        

        return mObject;

    }

    

    

    @Override

    protected void onActivityResult(int requestCode, int resultCode, Intent data) {

            super.onActivityResult(requestCode, resultCode, data);

     

            if(TAKE_PICTURE_CODE == requestCode){

                    

                if(Activity.RESULT_OK==resultCode){

                    processCameraImage(data);

                }else{

                    Toast.makeText(this, "You have not capture Image", Toast.LENGTH_SHORT).show();

                    

                     setContentView(R.layout.face_detect_layout);

                     

                        btn_facedetect=(Button)findViewById(R.id.detect_face);

                        btn_facedetect.setOnClickListener(this);

                         

                        

                        

                        btn_select_image=(Button)findViewById(R.id.btn_pickimag);

                        

                        btn_select_image.setOnClickListener(this);

                        

                        

                        imageView= (ImageView)findViewById(R.id.image_view);

                }

                

            }else if(SELECT_PICTURE==requestCode){

                

                

                if(Activity.RESULT_OK==resultCode){

                    

                    Uri selectedImageUri = data.getData();

                    String selectedImagePath = getPath(selectedImageUri);

                    

                    

                    setContentView(R.layout.face_detect_layout);

                    

                    btn_facedetect=(Button)findViewById(R.id.detect_face);

                    btn_facedetect.setOnClickListener(this);

                     

                    

                    

                    btn_select_image=(Button)findViewById(R.id.btn_pickimag);

                    

                    btn_select_image.setOnClickListener(this);

                    

                    

                    imageView= (ImageView)findViewById(R.id.image_view);

                    

                    updateImageFromGallary(selectedImagePath);

                    

                    

                    

                    

                    

                }else{

                    

                }

                

            }

            

            

    }

    

    

    private void updateImageFromGallary(String imgPath){

        

        try{

            

            cameraBitmap=null;

            

            //cameraBitmap=BitmapFactory.decodeFile(imgPath);

            

            cameraBitmap=decodeSampledBitmapFromResource(getResources(),imgPath,mWidth,mHeight);

            

            imageView.setImageBitmap(cameraBitmap);

            

            Toast.makeText(this, "Press Face detect for Face Detection", Toast.LENGTH_SHORT).show();

            

        }catch(OutOfMemoryError outMemeoryError){

            

            Toast.makeText(this, "Unable to Load Image", Toast.LENGTH_SHORT).show();

            

        }

        

        

        

        

    }

    

    

    private void startImagePicker(){

        

        // in onCreate or any event where your want the user to

        // select a file

        /*Intent intent = new Intent();

        intent.setType("image/*");

        intent.setAction(Intent.ACTION_GET_CONTENT);*/

        Intent intent = new Intent(Intent.ACTION_PICK,

                   android.provider.MediaStore.Images.Media.EXTERNAL_CONTENT_URI);

        

        startActivityForResult(Intent.createChooser(intent,

                "Select Picture"), SELECT_PICTURE);

        

    }

    

    

    public String getPath(Uri uri) {

        

        

        

         Uri selectedImage = uri;

         String[] filePathColumn = {MediaStore.Images.Media.DATA};



         Cursor cursor = getContentResolver().query(selectedImage, filePathColumn, null, null, null);

         

         cursor.moveToFirst();



         int columnIndex = cursor.getColumnIndex(filePathColumn[0]);

         String filePath = cursor.getString(columnIndex);

        

         return filePath;

        

       /* String[] projection = { MediaStore.Images.Media.DATA };

        Cursor cursor = managedQuery(uri, projection, null, null, null);

        int column_index = cursor

                .getColumnIndexOrThrow(MediaStore.Images.Media.DATA);

        cursor.moveToFirst();

        return cursor.getString(column_index);*/

    }

    

    

    public static int calculateInSampleSize(

            BitmapFactory.Options options, int reqWidth, int reqHeight) {

    // Raw height and width of image

    final int height = options.outHeight;

    final int width = options.outWidth;

    int inSampleSize = 1;



    if (height > reqHeight || width > reqWidth) {



        // Calculate ratios of height and width to requested height and width

        final int heightRatio = Math.round((float) height / (float) reqHeight);

        final int widthRatio = Math.round((float) width / (float) reqWidth);



        // Choose the smallest ratio as inSampleSize value, this will guarantee

        // a final image with both dimensions larger than or equal to the

        // requested height and width.

        inSampleSize = heightRatio < widthRatio ? heightRatio : widthRatio;

    }



    return inSampleSize;

}

    

    

    public static Bitmap decodeSampledBitmapFromResource(Resources res, String path,

            int reqWidth, int reqHeight) {



        // First decode with inJustDecodeBounds=true to check dimensions

        final BitmapFactory.Options options = new BitmapFactory.Options();

        options.inJustDecodeBounds = true;

       // BitmapFactory.decodeResource(res, resId, options);

       // BitmapFactory.decodeFile(path);

        

        BitmapFactory.decodeFile(path, options);

        // Calculate inSampleSize

        options.inSampleSize = calculateInSampleSize(options, reqWidth, reqHeight);



        // Decode bitmap with inSampleSize set

        options.inJustDecodeBounds = false;

       //return BitmapFactory.decodeResource(res, resId, options);

        

        return  BitmapFactory.decodeFile(path, options);

    }

    

    

    

    public class FaceDetectAsyncTask extends AsyncTask<Bitmap, Void, Object[]>{



        

        

        @Override

        protected void onPostExecute(Object[] result) {

            // TODO Auto-generated method stub

            super.onPostExecute(result);

            

            

            

            dismissProgressDialog();

            

            if(result!=null){

                

                if(result[0]!=null){

                    

                    int faceDetect=(Integer) result[0];

                    if(faceDetect>0){

                        

                        ImageView imageView = (ImageView)findViewById(R.id.image_view);

                         

                        imageView.setImageBitmap((Bitmap) result[1]);

                    }else{

                        Toast.makeText(FaceDetectActivity.this, "No Face Detect", Toast.LENGTH_SHORT).show();

                    }

                }else{

                    Toast.makeText(FaceDetectActivity.this, "No Face Detect", Toast.LENGTH_SHORT).show();

                }

                

                

            }

            

            

            

            

            

        }



        /*@Override

        protected void onPostExecute(Bitmap result) {

            // TODO Auto-generated method stub

            super.onPostExecute(result);

            

             dismissProgressDialog();

            

             ImageView imageView = (ImageView)findViewById(R.id.image_view);

             

             imageView.setImageBitmap(result);

             

            

        }

*/

        @Override

        protected void onPreExecute() {

            

            super.onPreExecute();

            

            showProgressDialog();

        }



        @Override

        protected Object[] doInBackground(Bitmap... params) {

            // TODO Auto-generated method stub

            

            Bitmap mBitmap=params[0];

            Object [] mObjArray;

            

            mObjArray=detectFaces(mBitmap);

            

            return mObjArray;

        }



        

    }

    

    

    private void showProgressDialog(){

        

        if(mProgressDialog!=null && mProgressDialog.isShowing()){

            return ;

        }else{

            mProgressDialog=new ProgressDialog(this);

            

            mProgressDialog.setTitle("Please wait...");

            

            mProgressDialog.setMessage("Detecting face from image");

            

            mProgressDialog.setCancelable(false);

            

            mProgressDialog.show();

        }

    }

    

    private void dismissProgressDialog(){

    

        if(mProgressDialog!=null && mProgressDialog.isShowing()){

            mProgressDialog.dismiss();

            mProgressDialog=null;

        }

    }

    

    

}





Here are my layout files  code:



activity_face_detection.xml





<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"

    xmlns:tools="http://schemas.android.com/tools"

    android:layout_width="match_parent"

    android:layout_height="match_parent"

    android:paddingBottom="@dimen/activity_vertical_margin"

    android:paddingLeft="@dimen/activity_horizontal_margin"

    android:paddingRight="@dimen/activity_horizontal_margin"

    android:paddingTop="@dimen/activity_vertical_margin"

    tools:context=".FaceDetectActivity"

    android:gravity="center"

     >



     <!-- <TextView 

        android:layout_width="fill_parent"

        android:layout_height="wrap_content"

        android:text="@string/app_info"

        android:gravity="center_horizontal"

        android:layout_weight="1.0"

        android:id="@+id/txt_appinfo"

        /> -->

         

    <Button

        android:layout_width="wrap_content"

        android:layout_height="wrap_content"

        android:id="@+id/take_picture"

        android:layout_margin="5dip"

        android:text="@string/take_picture"

        android:layout_gravity="center_horizontal"

        android:layout_centerHorizontal="true"

        

        

        />

    

    <Button

        android:layout_width="wrap_content"

        android:layout_height="wrap_content"

        android:id="@+id/btn_select_gallary"

        android:layout_margin="5dip"

        android:text="@string/select_image_from_gallary"

        android:layout_gravity="center_horizontal"

        android:layout_centerHorizontal="true"

        android:layout_below="@+id/take_picture"

        />



</RelativeLayout>



face_detect_layout.xml







<?xml version="1.0" encoding="utf-8"?>

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"

    android:layout_width="match_parent"

    android:layout_height="match_parent"

    android:orientation="vertical" >



    <ImageView

        android:id="@+id/image_view"

        android:layout_width="match_parent"

        android:layout_height="0dp"

        android:layout_weight="1.0" 

         />

    

    

    

    

    <LinearLayout

        

        android:layout_width="match_parent"

        android:layout_height="wrap_content"

         >

        

         <Button

        android:id="@+id/detect_face"

        android:layout_width="wrap_content"

        android:layout_height="wrap_content"

        

        android:text="@string/detect_face"

        android:layout_gravity="center_vertical"

         />

         

          <Button

        android:id="@+id/btn_pickimag"

        android:layout_width="wrap_content"

        android:layout_height="wrap_content"

       android:layout_gravity="center_vertical"

        android:text="@string/select_image_from_gallary" />

        

    </LinearLayout>



   



</LinearLayout>

Display Image from Redirected URL in android

noreply@blogger.com (Himanshu) — Wed, 31 Jul 2013 17:40:00 +0530

Today i am sharing one of my analysis for image load in android for redirected url.

Our Goal

We need to display image from URL that itself redirected to another URL.

For example http://graph.facebook.com/xxxxxxxxxxxx/picture/

Hit above URL on your browser, you will be redirected to actual URL like below.

http://profile.ak.fbcdn.net/hprofile-ak-ash3/623856_1060685508_1679122714_q.jpg

Problem when using third party library like lazy loading

I have seen many library uses HttpURLConnection class to display image from URL.

Like “Universal Image Loader” , “Android-Query ” but these library can't handle URL redirection.

So, you can also manage URL redirection using HttpURLConnection class itself.

Please read below explanation to get more idea and What is best approach.

Now, We have below Http clients which are used to download image from specified URL.

AndroidHttpClient
HttpURLConnection / HttpsURLConnection

3. DefaultHttpClient / HttpClient

1. AndroidHttpClient

This class does not support URL redirection automatically.
We need to write extra code to handle URL redirection.
You need to take care manually to close the connection of client.
It will handle HTTP to HTTPS URL redirection and vice versa.
It will handle only 1 URL redirection.

HttpURLConnection

This class does not support URL redirection automatically.
We need to write some code by setting property setInstanceFollowRedirects = false to handle URL redirection properly.
You need to take care manually to close the connection of client.
It will handle HTTP to HTTPS URL redirection and vice versa.
This class handles up to 5 redirection.

DefaultHttpClient / HttpClient

This class by default support URL redirection automatically.
We need not to write any code.
No need to close the connection.
It will handle HTTP to HTTPS URL redirection and vice versa.
This class handles greater than five redirection. I am not able to find maximum limit.

Conclusion

From above explanation, Winner is DefaultHttpClient. We must use DefaultHttpClient class. This class also handles Cookie forward mechanism very well if we use singleton pattern in cookie based authentication process in project.

Now below are code for above example.

Below is my main Activity class.

public class MainActivity extends Activity implements OnClickListener{

private static String TAG = MainActivity.class.getSimpleName();

private Button btnAndroidHttpClient, btnDownloadHttpURLConnection, btnDownloadDefaultHttpClient;

private ImageView imgView;

private DefaultHttpClient client = null;

/**

* put your URL that itself redirected to another url that is the actual url to download image

private static final String URL_AndroidHttp = "http://graph.facebook.com/xxxxxxxxxxxx/picture/";

private static final String URL_HttpUrlConnection = "http://wired.ivvy.com/image/display/account/14/file/119806";

private static final String URL_DefaultHttp = "http://graph.facebook.com/xxxxxxxxxxxx/picture/";

@Override

protected void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.activity_main);

btnAndroidHttpClient = (Button) findViewById(R.id.btnDownloadAndroidHttpClient);

btnAndroidHttpClient.setOnClickListener(this);

btnDownloadHttpURLConnection = (Button)findViewById(R.id.btnDownloadHttpURLConnection);

btnDownloadHttpURLConnection.setOnClickListener(this);

btnDownloadDefaultHttpClient = (Button) findViewById(R.id.btnDownloadDefaultHttpClient);

btnDownloadDefaultHttpClient.setOnClickListener(this);

imgView = (ImageView)findViewById(R.id.imgView);

}

@Override

public void onClick(View v) {

switch (v.getId()) {

case R.id.btnDownloadAndroidHttpClient:

if(Utils.isNetworkAvailable(MainActivity.this))

{

if(URL_AndroidHttp != null || !URL_AndroidHttp.equalsIgnoreCase(""))

{

new DownloadImageViaAndroidHttpClientTask().execute(URL_AndroidHttp,imgView);

}

else

{

Toast.makeText(MainActivity.this, "Please provide image url.", Toast.LENGTH_SHORT).show();

}

else

{

Toast.makeText(MainActivity.this, "Please check your internet connectivity.", Toast.LENGTH_SHORT).show();

}

break;

case R.id.btnDownloadHttpURLConnection:

if(Utils.isNetworkAvailable(MainActivity.this))

{

if(URL_HttpUrlConnection != null || !URL_HttpUrlConnection.equalsIgnoreCase(""))

{

new DownloadImageViaHttpURLConnectionTask().execute(URL_HttpUrlConnection,imgView);

}

else

{

Toast.makeText(MainActivity.this, "Please provide image url.", Toast.LENGTH_SHORT).show();

}

else

{

Toast.makeText(MainActivity.this, "Please check your internet connectivity.", Toast.LENGTH_SHORT).show();

}

break;

case R.id.btnDownloadDefaultHttpClient:

if(Utils.isNetworkAvailable(MainActivity.this))

{

if(URL_DefaultHttp != null || !URL_DefaultHttp.equalsIgnoreCase(""))

{

new DownloadImageViaDefaultHttpClientTask().execute(URL_DefaultHttp,imgView);

}

else

{

Toast.makeText(MainActivity.this, "Please provide image url.", Toast.LENGTH_SHORT).show();

}

else

{

Toast.makeText(MainActivity.this, "Please check your internet connectivity.", Toast.LENGTH_SHORT).show();

}

break;

}

class DownloadImageViaAndroidHttpClientTask extends AsyncTask<Object, Void, Drawable>

{

private ImageView imgView;

private ProgressDialog dialog;

private AndroidHttpClient androidHttpClient = AndroidHttpClient.newInstance("Android");

@Override

protected void onPreExecute() {

dialog = new ProgressDialog(MainActivity.this);

dialog.setMessage("Please wait...");

dialog.show();

}

@Override

protected Drawable doInBackground(Object... params) {

imgView = (ImageView) params[1];

try {

HttpGet httpGet=new HttpGet((String)params[0]);

HttpResponse httpResponse=androidHttpClient.execute(httpGet);

androidHttpClient.close();

final int statusCode = httpResponse.getStatusLine().getStatusCode();

if (statusCode != HttpStatus.SC_OK) {

Header[] headers = httpResponse.getHeaders("Location");

if (headers != null && headers.length != 0) {

String newUrl = headers[headers.length - 1].getValue();

AppLog.i(TAG, "newUrl=>"+newUrl);

/**

* call again with new URL to get image

return downloadImage(newUrl);

} else {

return null;

}

catch (Exception ex)

{

AppLog.e(TAG, "DownloadImageTask doInBackground() Exception=>"+ex);

}

return null;

}

@Override

protected void onPostExecute(Drawable drawable) {

if (dialog.isShowing()) {

dialog.dismiss();

}

if(drawable != null)

{

imgView.setImageDrawable(drawable);

}

class DownloadImageViaHttpURLConnectionTask extends AsyncTask<Object, Void, Drawable>

{

private ImageView imgView;

private ProgressDialog dialog;

private HttpURLConnection con = null;

@Override

protected void onPreExecute() {

dialog = new ProgressDialog(MainActivity.this);

dialog.setMessage("Please wait...");

dialog.show();

}

@Override

protected Drawable doInBackground(Object... params) {

imgView = (ImageView) params[1];

try {

con = (HttpURLConnection)(new URL((String)params[0]).openConnection());

con.disconnect();

con.setInstanceFollowRedirects(false);

con.connect();

final int responseCode = con.getResponseCode();

AppLog.i(TAG, "responseCode=>"+responseCode);

if (responseCode != HttpStatus.SC_OK) {

String newUrl = con.getHeaderField("Location");;

AppLog.i(TAG, "newUrl=>"+newUrl);

return downloadImage(newUrl);

}

catch (Exception ex)

{

AppLog.e(TAG, "DownloadImageTask doInBackground() Exception=>"+ex);

}

finally

{

if(con != null)

{

con.disconnect();

con= null;

}

return null;

}

@Override

protected void onPostExecute(Drawable drawable) {

if (dialog.isShowing()) {

dialog.dismiss();

}

if(drawable != null)

{

imgView.setImageDrawable(drawable);

}

class DownloadImageViaDefaultHttpClientTask extends AsyncTask<Object, Void, Drawable>

{

private ImageView imgView;

private ProgressDialog dialog;

@Override

protected void onPreExecute() {

dialog = new ProgressDialog(MainActivity.this);

dialog.setMessage("Please wait...");

dialog.show();

}

@Override

protected Drawable doInBackground(Object... params) {

imgView = (ImageView) params[1];

try {

/**

* check for whether client os initialized or not. first time it is null, after first request

* it will not create client. it will use existing initialized client to reduce memory consumption and improve performance.

* It will also used to cookie based implementation if we are using only one instance of client to redirect cookie to further request.

if(client==null)

{

createClient();

}

HttpParams httpParams = client.getParams();

httpParams.setIntParameter("http.connection.timeout", 30000); // 30 SECONDS

httpParams.setIntParameter("http.socket.timeout", 30000); // 30 SECONDS

HttpGet httpGet=new HttpGet((String)params[0]);

HttpResponse httpResponse=client.execute(httpGet);

InputStream is=httpResponse.getEntity().getContent();

Drawable d = Drawable.createFromStream(is, "src name");

is.close();

return d;

}

catch (Exception ex)

{

AppLog.e(TAG, "DownloadImageTask doInBackground() Exception=>"+ex);

}

return null;

}

@Override

protected void onPostExecute(Drawable drawable) {

if (dialog.isShowing()) {

dialog.dismiss();

}

if(drawable != null)

{

imgView.setImageDrawable(drawable);

}

private static Drawable downloadImage(String stringUrl) {

URL url = null;

HttpURLConnection connection = null;

InputStream inputStream = null;

try {

url = new URL(stringUrl);

connection = (HttpURLConnection) url.openConnection();

connection.setUseCaches(true);

inputStream = connection.getInputStream();

Drawable d = Drawable.createFromStream(inputStream, "src name");

inputStream.close();

return d;

} catch (Exception e) {

AppLog.e(TAG, "Error while retrieving bitmap from " + e);

} finally {

if (connection != null) {

connection.disconnect();

}

return null;

}

public void createClient() {

BasicHttpParams params = new BasicHttpParams();

SchemeRegistry schemeRegistry = new SchemeRegistry();

schemeRegistry.register( new Scheme("http", PlainSocketFactory.getSocketFactory(), 80));

schemeRegistry.register( new Scheme("https", SSLSocketFactory.getSocketFactory(), 443));

ClientConnectionManager ccm = new ThreadSafeClientConnManager( params, schemeRegistry);

client = new DefaultHttpClient( ccm, params);

}

----------------------------------------------------------------------------------------------------------

public class AppLog {

private static boolean sFlagDebug= true;

private static boolean sFlagInfo= true;

private static boolean sFlagErr= true;

/**

* THis will print in Blue

* @param tag

* @param message

public static void d(String tag, String message){

if(sFlagDebug)

{

Log.d(tag,message);

}

/**

* This will print in Green

* @param tag

* @param message

public static void i(String tag, String message){

if(sFlagInfo)

{

Log.i(tag,message);

}

/**

* This will print in Error

* @param tag

* @param message

public static void e(String tag, String message){

if(sFlagErr)

{

Log.e(tag,message);

}

---------------------------------------------------------------------------------------------------------

public class Utils {

private static final String TAG = Utils.class.getSimpleName();

/**

* Check Internet connection flag.

* @param context

* @return

public static boolean isNetworkAvailable(Context context) {

ConnectivityManager connectivityManager = (ConnectivityManager) context

.getSystemService(Context.CONNECTIVITY_SERVICE);

final NetworkInfo networkInfo = connectivityManager

.getActiveNetworkInfo();

if (networkInfo != null && networkInfo.isConnectedOrConnecting()) {

return true;

}

return false;

}

Loading Large Bitmaps Efficiently in android

noreply@blogger.com (Himanshu) — Fri, 4 Jan 2013 15:26:00 +0530

Below is code for loading large image from url in android mobile.

Below is code for loading large image from url in android mobile.

public class ImageLoadActivity extends Activity {
ImageView mImageView;
BitmapWorkTask mBitmapWorkTask;
public static final String URL="http://www.iiccentre.org/image/Restaurants.jpg";
public static final String URL2="http://nssdc.gsfc.nasa.gov/planetary/image/cassini_titan_15.jpg";
ProgressDialog mProgressDialog;
public static int deviceHeight;
public static int deviceWidth;
DisplayMetrics dm;

@Override protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_image_load);
displayIntialize();
mImageView=(ImageView)findViewById(R.id.img_loaded);
mBitmapWorkTask=new BitmapWorkTask();
mBitmapWorkTask.execute(URL,URL2);

}

private void displayIntialize(){
dm= new DisplayMetrics();
getWindowManager().getDefaultDisplay().getMetrics(dm);
deviceHeight=dm.heightPixels;
deviceWidth=dm.widthPixels;

}

@Override
public boolean onCreateOptionsMenu(Menu menu) { // Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.activity_image_load, menu);
return true;
}

public class BitmapWorkTask extends AsyncTask{

@Override
protected void onPreExecute() {
super.onPreExecute();
mProgressDialog=new ProgressDialog(ImageLoadActivity.this, ProgressDialog.STYLE_SPINNER);
mProgressDialog=ProgressDialog.show(ImageLoadActivity.this, "Please wait", "While image is loading");
mProgressDialog.show();
}

protected void onPostExecute(Bitmap result) {
// TODO Auto-generated method stub
super.onPostExecute(result);
if(result!=null){
mImageView.setImageBitmap(result);

}
if(mProgressDialog!=null){
mProgressDialog.dismiss();
}
}
@Override protected Bitmap doInBackground(String... params) {
Bitmap mBitmap=null;
int size=params.length;
String urlIs=params[1];
mBitmap=downloadBitmap(urlIs);
return mBitmap;
}
}

static Bitmap downloadBitmap(String url) {
final AndroidHttpClient client = AndroidHttpClient.newInstance("Android");
final HttpGet getRequest = new HttpGet(url);
try {
HttpResponse response = client.execute(getRequest);
final int statusCode = response.getStatusLine().getStatusCode();
if (statusCode != HttpStatus.SC_OK) {

Log.w("ImageDownloader", "Error " + statusCode + " while retrieving bitmap from " + url);
return null;
}
final HttpEntity entity = response.getEntity();
if (entity != null) {
InputStream inputStream = null;
try {
inputStream = entity.getContent();
BufferedInputStream bis = new BufferedInputStream(inputStream);
bis.mark(1024 * 1024);
final Bitmap bitmap = decodeSampledBitmapFromResource(bis,deviceWidth,deviceHeight);
return bitmap;
} finally {
if (inputStream != null) {
inputStream.close();
}
entity.consumeContent();
}
}
} catch (Exception e) { // Could provide a more explicit error message for IOException or IllegalStateException
getRequest.abort();
//Log.w("ImageDownloader", "Error while retrieving bitmap from " + url, e.toString());
Log.e("LOG_TAG", "Error while retrieving bitmap from" + url + e.toString());
} finally {
if (client != null) {
client.close();
}
} return null;

}

public static Bitmap decodeSampledBitmapFromResource(BufferedInputStream inputStream,int reqWidth, int reqHeight) { // First decode with
//inJustDecodeBounds=true
//to check dimensions
final BitmapFactory.Options options = new BitmapFactory.Options();
options.inJustDecodeBounds = true;
BitmapFactory.decodeStream(inputStream, null, options); // Calculate inSampleSize
options.inSampleSize = calculateInSampleSize(options, reqWidth, reqHeight); // Decode bitmap with inSampleSize set
options.inJustDecodeBounds = false;
try {
inputStream.reset();
} catch (IOException e) {
e.printStackTrace();
}

return BitmapFactory.decodeStream(inputStream, null, options);

}

public static int calculateInSampleSize(BitmapFactory.Options options, int reqWidth, int reqHeight) { // Raw height and width of image
final int height = options.outHeight;
final int width = options.outWidth;
int inSampleSize = 1;
if (height > reqHeight || width > reqWidth) {
if (width > height) {
inSampleSize = Math.round((float) height / (float) reqHeight);
} else {
inSampleSize = Math.round((float) width / (float) reqWidth);
}
} return inSampleSize;
}
}

}

}

}

Here is output:

Android Custom ListView with Seekbar ,TextView and Button

noreply@blogger.com (Himanshu) — Fri, 4 May 2012 12:16:00 +0530


In this Example you can see how to use Custom Listview with Seekbar ,TextView and Button in android ListView.

Below is code for Activity which have ListView .



public class SeekBarExampleActivity extends ListActivity implements
  OnClickListener, OnTouchListener, OnSeekBarChangeListener {
 /** Called when the activity is first created. */
 ListView mListView;
 public static final int TOTAL_ITEM = 25;

 ImageView mImageView;
 ArrayList mSeekbarValue;

 ImageButton mImageButton;
 ListAdapter mListAdapter;
 TextView mTempTextview;

 @Override
 public void onCreate(Bundle savedInstanceState) {
  super.onCreate(savedInstanceState);
  setContentView(R.layout.main);
  mListView = getListView();
  mSeekbarValue = new ArrayList(TOTAL_ITEM);
  for(int i=0;i adapter, View view,
    int position, long lon) {

  }
 };

 @Override
 public boolean onTouch(View v, MotionEvent event) {
  Log.v("Log_tag", "LinearView is Click");
  /*LinearLayout mLinearlayout = (LinearLayout) v;
  if (mLinearlayout.getChildCount() > 0) {
   LinearLayout mtopLinearlayout = (LinearLayout) mLinearlayout
     .getChildAt(0);
   mTempTextview = (TextView) mtopLinearlayout.getChildAt(0);
   Log.v("Log_tag", "Tecview chnage");
  }*/

  return false;
 }

 @Override
 public void onProgressChanged(SeekBar seekBar, int progress,
   boolean fromUser) {
  int position = seekBar.getId();
  LinearLayout mLinearlayout=(LinearLayout) seekBar.getParent();
  if (mLinearlayout.getChildCount() > 0) {
   LinearLayout mtopLinearlayout = (LinearLayout) mLinearlayout
     .getChildAt(0);
   mTempTextview = (TextView) mtopLinearlayout.getChildAt(0);
   Log.v("Log_tag", "Tecview chnage");
  }
  //mSeekbarValue.add(position, progress);
  mSeekbarValue.set(position, progress);
  updateTextview(progress);
 }

 @Override
 public void onStartTrackingTouch(SeekBar seekBar) {

 }

 @Override
 public void onStopTrackingTouch(SeekBar seekBar) {

 }

 public void updateTextview(int paramValue) {
  if (mTempTextview != null) {
   mTempTextview.setText(String.valueOf(paramValue));
  }
 }
}



Here is My Row xml used for Custom ListView:

list_row_view.xml:





    

        

        

    



main.xml

Android Dialog with Custom View

noreply@blogger.com (Himanshu) — Fri, 20 Apr 2012 00:00:00 +0530

You can create Android Dialog with Below code .

public class DatePickerDialogActivity extends Activity {

@Override
public boolean onMenuItemSelected(int featureId, MenuItem item) {
// TODO Auto-generated method stub
return super.onMenuItemSelected(featureId, item);
}

@Override
public boolean onMenuOpened(int featureId, Menu menu) {
// TODO Auto-generated method stub
return super.onMenuOpened(featureId, menu);
}

@Override
public boolean onOptionsItemSelected(MenuItem item) {
// TODO Auto-generated method stub
return super.onOptionsItemSelected(item);
}

@Override
public void onOptionsMenuClosed(Menu menu) {
// TODO Auto-generated method stub
super.onOptionsMenuClosed(menu);
}

public static final int DATE_PICKER_DIALOG=1;
public static final int MY_NEW_DIALOG=2;
public Calendar mCalendar;
int mYear;
int mMonth;
int mDay;
String mStringdate="04/04/2012";
String mStrdate1="2012-04-04";
public DatePickerDialog mDatePickerDialog;
public Dialog mDialog;
public Button mButton;
@Override
protected Dialog onCreateDialog(int id) {
switch(id){

case DATE_PICKER_DIALOG:
mDatePickerDialog=new DatePickerDialog(this, new DatePickerDialog.OnDateSetListener() {
@Override
public void onDateSet(DatePicker view, int year, int monthOfYear,
int dayOfMonth) {
view.setOnClickListener(mDateSetListener);
mYear=year + 1;
mMonth=monthOfYear;
mDay=dayOfMonth;
Log.v("Log_tag", "Year is " + mYear +"month is "+ monthOfYear +"Day is "+ dayOfMonth);
}
}, mYear, mMonth, mDay);
mDatePickerDialog.setTitle(R.string.date_set_message);

return mDatePickerDialog;
case MY_NEW_DIALOG:
mSimpleDialog=new Dialog(this,R.style.CustomDialogTheme);
mSimpleDialog.setContentView(R.layout.dialog_layout);
TextView mTextView=(TextView)findViewById(R.id.msgtxt);
Button mBtnYes=(Button)mSimpleDialog.findViewById(R.id.btn_yes);
Button mBtnNo=(Button)mSimpleDialog.findViewById(R.id.btn_no);
mBtnYes.setOnClickListener(DialogButtonClickListener);
mBtnNo.setOnClickListener(DialogButtonClickListener);
mSimpleDialog.setCancelable(true);
mSimpleDialog.show();
return mSimpleDialog;

}
return null;
}

@Override
protected void onPrepareDialog(int id, Dialog dialog) {

super.onPrepareDialog(id, dialog);
}

OnClickListener mDateSetListener =new OnClickListener() {

@Override
public void onClick(View v) {

Log.v("Log_tag", "Set Date is done");
}
};

OnClickListener mButtonClickListener =new OnClickListener() {

@Override
public void onClick(View v) {

if(mDatePickerOn){
showDialog(DATE_PICKER_DIALOG);
}else{
showDialog(MY_NEW_DIALOG);
}

Log.v("Log_tag", "Set Date is done");

}
};

Dialog mSimpleDialog;
ToggleButton mToggleButton;
boolean mDatePickerOn=false;

/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
// requestWindowFeature(Window.)
super.onCreate(savedInstanceState);
setContentView(R.layout.my_dialog);
mCalendar=Calendar.getInstance();
mYear=mCalendar.get(Calendar.YEAR);
mMonth=mCalendar.get(Calendar.MONTH);
mDay=mCalendar.get(Calendar.DAY_OF_MONTH);
mButton=(Button)findViewById(R.id.btn_show_calander);
mButton.setOnClickListener(mButtonClickListener);
mToggleButton=(ToggleButton)findViewById(R.id.toogleButton);
mToggleButton.setOnCheckedChangeListener(mOnCheckedChangeListener);
SimpleDateFormat mSimpleDateFormat=new SimpleDateFormat("EEE, MMM d, ''yy");
SimpleDateFormat curFormater = new SimpleDateFormat("dd/MM/yyyy");
try {
//dateobj1= mSimpleDateFormat.parse(mStrdate1);
Date dateObj = curFormater.parse(mStringdate);
SimpleDateFormat postFormater = new SimpleDateFormat("EEE,MMMM dd, yyyy");
String newDateStr = postFormater.format(dateObj);
// date2=mSimpleDateFormat.format(dateobj1);
//dateobj=mSimpleDateFormat.parse(mStringdate);
//String dateis=mSimpleDateFormat.format(dateobj);
Log.v("Log_tag", "Here we are with Date Function"+ newDateStr);
} catch (ParseException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}

}

OnCheckedChangeListener mOnCheckedChangeListener=new OnCheckedChangeListener() {

@Override
public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {

if(isChecked){
mDatePickerOn=true;
}else{
mDatePickerOn=false;
}
}
};

View.OnClickListener DialogButtonClickListener=new View.OnClickListener() {

@Override
public void onClick(View v) {
switch(v.getId()){
case R.id.btn_yes:
finish();
break;
case R.id.btn_no:
mSimpleDialog.dismiss();
break;
}

}
};
}

Here is xml Layout for Custom Dialog .
dialog_layout.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:background="@drawable/dialog_bg"
android:orientation="vertical" >

<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center_horizontal"
android:layout_marginTop="35dp"
android:text="@string/hello"
android:id="@+id/msgtxt"/>

<LinearLayout
android:id="@+id/btn_linerLayout"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:orientation="horizontal"
android:paddingLeft="10dp"
android:paddingRight="10dp"
android:gravity="center_horizontal"
android:layout_marginTop="50dp">

<Button
android:id="@+id/btn_yes"
android:layout_width="125dp"
android:layout_height="40dp"
android:layout_gravity="center_vertical"

android:text="@string/btn_yes"
android:layout_marginRight="5dp" />

<Button
android:id="@+id/btn_no"
android:layout_width="125dp"
android:layout_height="40dp"
android:layout_gravity="center_vertical"

android:text="@string/btn_no"
android:layout_marginLeft="5dp"/>
</LinearLayout>

</LinearLayout>

Another xml layout that used in Example is below
my_dialog.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >

<Button
android:id="@+id/btn_show_calander"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:onClick="mButtonClickListener"
android:text="@string/btn_text" />

<ToggleButton
android:id="@+id/toogleButton"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="ToggleButton"
android:textOn="@string/text_toggle_on"
android:textOff="@string/text_toggle_off"
android:gravity="center"/>

</LinearLayout>

Android Vs iPhone : Do iOS Apps Crash More Than Android Apps? A Data Dive.

noreply@blogger.com (Himanshu) — Sat, 4 Feb 2012 15:42:00 +0530

Ever wonder why certain mobile apps you use crash so much?

It turns out there are many possible reasons. And it can vary particularly depending on whether you are using an Apple iOS device such as an iPhone or iPad, or an Android device.

One of the reasons for app crashes is the proliferation of mobile operating systems on iOS and Android. As Apple and Google have released more new operating systems, each with multiple updates, app developers face more operating systems to test apps on. In data that mobile app monitoring startup Crittercism compiled for app crashes between December 1 and 15, there were at least 23 different iOS operating systems on which apps had crashed and 33 Android operating systems on which apps had crashed. (See the graphs above.) Note that the graphs that separate out Android and iOS show these number of operating systems and the graph that combines both iOS and Android shows less–22 iOS and 17 Android.

The largest proportion of app crashes from both iOS and Android platforms were on iOS 5.01 with 28.64% of overall crashes (in a normalized data set). That makes sense since iOS 5 was still relatively new at that time and many apps still need to work out the kinks with the new OS. But there are also older iOS versions that have a significant proportion of app crashes. For example, iOS 4.2.10 had 12.64% of app crashes, iOS 4.3.3 had 10.66% and iOS 4.1 had 8.24%. One other point that this made clear to me is that many people apparently take their time updating their iPhone software or never update it at all.

The data raises two main questions for me: why do apps on these operating systems crash so much, and do iOS apps crash more than Android apps? On the first question of why apps crash, the reasons are many, says Crittercism CEO Andrew Levy. This can be due to hardware issues, such as the use of location or GPS services or cameras; it could be due to the Internet connection, that is, how a phone connects to 3G or WiFi, or that the device is not connected to the Internet at a certain moment, or that something happens during the switch between 3G and WiFi. There could also be issues with language support on certain devices. There can also be memory problems if an app uses too much memory.

Problems can also occur with third-party services that developers use in their apps, from analytics to advertising systems. For example, there were reports that Apple’s iAds system gave some developers problems if they did not adhere to certain standards. ”It can be a mix of both hardware and software issues that developers may or may not be responding to,” Levy says.

In addition, developers also constantly create new updates to their apps to create new features or fix bugs. But again, people often don’t update their apps–just as they don’t update their operating system. (Android, unlike iOS, allows users to auto-update their apps, which can eliminate some of the problems.) So developers often test all previous versions of their apps with each version of the different operating systems. ”The permutations go on forever,” Levy says. “That’s a large reason for creating our platform.” Particularly with a new OS, developers have to test their app to make sure it still works on the new OS. Often they will seek to test their apps in a test environment, but often that isn’t possible.

The Apple iOS operating system app crashes accounted for more of the app crashes in Crittercism’s data than did Android-based phones, as mentioned above. In the pie graph “Crashes by OS Version Normalized” you can see that iOS accounted for close to three-fourths of the app crashes, with Android making up the rest. But is that just because Crittercism has more iOS phones in its network? Crittercism parsed some data to answer that question.

Crittercism analyzed a total of more than 214 million app launches from November and December 2011 from apps that use its service (see graph at top of this article). There were about 3 times more app launches for iOS that Crittercism analyzed, about 162 million to 52 million. But the analysis examined app crashes as a percentage of each app launch, so this data takes out the issue of there being more iOS than Android apps. In other words for each iOS app and each Android app how often percentage-wise do they crash?

In the top quartile of apps, Android apps crashed 0.15% of the time they launched, while top quartile iOS apps crashed 0.51% of the time. In the second quartile of apps, Android apps crashed 0.73% of the time and iOS apps crashed 1.47% of their launches. In the third quartile of apps, Android apps crashed 2.97% of the time, while iOS apps crashed 3.66% of the time.

So what does all this data mean? On a basic level, you can see that iOS apps crashed more than Android apps during this time period. But Crittercism’s Levy cautions that this doesn’t necessarily mean that overall iOS apps crash more than Android apps. That’s because Apple had recently released a new version iOS 5 in October. Android’s new Ice Cream Sandwich operating system (Android 4.0), meanwhile, had not been widely released on phones yet at the time of this study. “I expect as Ice Cream Sandwich just launched and the new Nexus S phone launched (during the study), we’ll expect the same situation to occur (with Android) as what happened (with iOS),” Levy says.

Still, the data shows that apps on iOS did crash substantially more than Android apps. Anecdotally, I know that certain apps I use on my iPhone crash and they crash often. Will that change as Ice Cream Sandwich rolls out and as more developers improve on iOS 5? We’ll see.

One other thing about the data: in the best apps, that is, the top quartile, the apps crashed much less than in the third quartile. Levy emphasized that that shows the difference that developers can make with their apps by analyzing the data and improving their apps. Splitting up the data by quartiles also removes apps with massive user bases that can skew the averages.

My own point: when you get to the top apps, Android’s lower app crash rate than iOS makes less of a difference because they are both well below 1%. However, there was a bigger difference between iOS and Android app crashes in the top quartile of apps than in the third quartile. In other words, the best apps in Android crashed about one third as many times as the best iOS apps, while the second best quartile Android apps crashed about half as much as comparable iOS apps, and in the quartile, the difference between the two operatings systems was even less. So the very top Android apps are achieving a crash rate that, at least in this time period, the best iOS apps can’t match. Why that is, I’m not entirely clear.

However, Android, it should be noted, allows developers to push updates faster than Apple. With Android developers can just send an update to its code, which can show up almost in real-time. But for iOS it can takes days or a week for an update to show up. That means there can be more app crashes while those updates are waiting to happen. Whereas with Android, presumably if developers know there’s a bug they can immediately fix it.

One final piece of interesting data from Crittercism: The performance of apps is not only different on various operating systems but also on different devices. About 74.41% of the iOS crashes Crittercism tracked were on the iPhone, 14.81% were on the iPod Touch, and 10.72% were on the iPad.

Crittercism, which is backed by Google Ventures, Kleiner Perkins Caufield & Byers, AngelPad, AOL Ventures, Opus Capital and Shasta Ventures, provides crash reporting to app developers. The company provides developers with a wide range of data besides the mobile device and operating system, including, for example, the length of time between when an app is loaded and when it crashes, or how a user is holding a phone–portrait or landscape–when it crashes. It can also help evaluate whether an app’s own code has caused it to crash or whether a third party service SDK being used is causing the problem. This kind of data is important for helping developers plug all the holes in the landscape of operating systems. Clients using Crittercism include: Aston Martin Explore, Bullet Time and Hipster.

Protecting apps from crashes is not only important for app developers, who by definition live and die by the ability of their apps to work smoothly. Increasingly, many types of companies rely on apps to run their businesses, even if there isn’t a large consumer user base using the apps. Banks have mobile apps that enable check deposits, sales people use apps in the field, and so on. “It’s about protecting your brand,” says Crittercism cofounder Rob Kwok. “More and more business-critical functions are moving to apps.”

Crittercism is signing up a number of large customers to its platform as a result. The company has already ramped way up from the 214 million app launches that it monitored in this data from November and December. If you’re hoping to end those annoying crashes on your phone or tablet, that should be welcome news.

Android Graphics : Some Fact About Android Graphics

noreply@blogger.com (Himanshu) — Wed, 1 Feb 2012 21:59:00 +0530

Here Some Interesting Things About Android Graphics By Post of Dianne Hackborn.

• Android has always used some hardware accelerated drawing. Since before 1.0 all window compositing to the display has been done with hardware.

• This means that many of the animations you see have always been hardware accelerated: menus being shown, sliding the notification shade, transitions between activities, pop-ups and dialogs showing and hiding, etc.

• Android did historically use software to render the contents of each window. For example in a UI like http://www.simplemobilereview.com/wp-content/uploads/2010/12/2-home-menu.png there are four windows: the status bar, the wallpaper, the launcher on top of the wallpaper, and the menu. If one of the windows updates its contents, such as highlighting a menu item, then (prior to 3.0) software is used to draw the new contents of that window; however none of the other windows are redrawn at all, and the re-composition of the windows is done in hardware. Likewise, any movement of the windows such as the menu going up and down is all hardware rendering.

• Looking at drawing inside of a window, you don’t necessarily need to do this in hardware to achieve full 60fps rendering. This depends very much on the number of pixels in your display and the speed of your CPU. For example, Nexus S has no trouble doing 60fps rendering of all the normal stuff you see in the Android UI like scrolling lists on its 800x480 screen. The original Droid however struggled with a similar screen resolution.

• "Full" hardware accelerated drawing within a window was added in Android 3.0. The implementation in Android 4.0 is not any more full than in 3.0. Starting with 3.0, if you set the flag in your app saying that hardware accelerated drawing is allowed, then all drawing to the application’s windows will be done with the GPU. The main change in this regard in Android 4.0 is that now apps that are explicitly targeting 4.0 or higher will have acceleration enabled by default rather than having to put android:handwareAccelerated="true" in their manifest. (And the reason this isn’t just turned on for all existing applications is that some types of drawing operations can’t be supported well in hardware and it also impacts the behavior when an application asks to have a part of its UI updated. Forcing hardware accelerated drawing upon existing apps will break a significant number of them, from subtly to significantly.)

• Hardware accelerated drawing is not all full of win. For example on the PVR drivers of devices like the Nexus S and Galaxy Nexus, simply starting to use OpenGL in a process eats about 8MB of RAM. Given that our process overhead is about 2MB, this is pretty huge. That RAM takes away from other things, such as the number of background processes that can be kept running, potentially slowing down things like app switching.

• Because of the overhead of OpenGL, one may very well not want to use it for drawing. For example some of the work we are doing to make Android 4.0 run well on the Nexus S has involved turning off hardware accelerated drawing in parts of the UI so we don’t lose 8MB of RAM in the system process, another 8MB in the phone process, another 8MB in the system UI process, etc. Trust me, you won’t notice -- there is just no benefit on that device in using OpenGL to draw something like the status bar, even with fancy animations going on in there.

• Hardware accelerated drawing is not a magical silver bullet to butter-smooth UI. There are many different efforts that have been going on towards this, such as improved scheduling of foreground vs. background threads in 1.6, rewriting the input system in 2.3, strict mode, concurrent garbage collection, loaders, etc. If you want to achieve 60fps, you have 20 milliseconds to handle each frame. This is not a lot of time. Just touching the flash storage system in the thread that is running the UI can in some cases introduce a delay that puts you out of that timing window, especially if you are writing to storage.

• A recent example of the kinds of interesting things that impact UI smoothness: we noticed that ICS on Nexus S was actually less smooth when scrolling through lists than it was on Gingerbread. It turned out that the reason for this was due to subtle changes in timing, so that sometimes in ICS as the app was retrieving touch events and drawing the screen, it would go to get the next event slightly before it was ready, causing it to visibly miss a frame while tracking the finger even though it was drawing the screen at a solid 60fps. (Edit: for those who need this made clear, yes of course this particular issue is fixed.)

• When people have historically compared web browser scrolling between Android and iOS, most of the differences they are seeing are not due to hardware accelerated drawing. Originally Android went a different route for its web page rendering and made different compromises: the web page is turned in to a display list, which is continually rendered to the screen, instead of using tiles. This has the benefit that scrolling and zooming never have artifacts of tiles that haven’t yet been drawn. Its downside is that as the graphics on the web page get more complicated to draw the frame rate goes down. As of Android 3.0, the browser now uses tiles, so it can maintain a consistent frame rate as you scroll or zoom, with the negative of having artifacts when newly needed tiles can’t be rendered quickly enough. The tiles themselves are rendered in software, which I believe is the case for iOS as well. (And this tile-based approach could be used prior to 3.0 without hardware accelerated drawing; as mentioned previously, the Nexus S CPU can easily draw the tiles to the window at 60fps.)

• Hardware accleration does not magically make drawing performance problems disappear. There is still a limit to how much the GPU can do. A recent interesting example of this is tablets built with Tegra 2 -- that GPU can touch every pixel of a 1280x800 screen about 2.5 times at 60fps. Now consider the Android 3.0 tablet home screen where you are switching to the all apps list: you need to draw the background (1x all pixels), then the layer of shortcuts and widgets (let’s be nice and say this is .5x all pixels), then the black background of all apps (1x all pixels), and the icons and labels of all apps (.5x all pixels). We’ve already blown our per-pixel budget, and we haven’t even composited the separate windows to the final display yet. To get 60fps animation, Android 3.0 and later use a number of tricks. A big one is that it tries to put all windows into overlays instead of having to copy them to the framebuffer with the GPU. In the case here even with that we are still over-budget, but we have another trick: because the wallpaper on Android is in a separate window, we can make this window larger than the screen to hold the entire bitmap. Now, as you scroll, the movement of the background doesn’t require any drawing, just moving its window... and because this window is in an overlay, it doesn’t even need to be composited to the screen with the GPU.

• As device screen resolution goes up, achieving a 60fps UI is closely related to GPU speed and especially the GPU’s memory bus bandwidth. In fact, if you want to get an idea of the performance of a piece of hardware, always pay close attention to the memory bus bandwidth. There are plenty of times where the CPU (especially with those wonderful NEON instructions) can go a lot faster than the memory bus.

EDIT:

Wow this has generated a lot more discussion, and I won't be able to address nearly everything that has been raised. But I'll try to expand on things a bit here to better address what I think are some of the more interesting points.

Some have raised points along the lines of Samsung Galaxy S2 phones already having a smoother UI and indicating that they are doing something different vs. the Galaxy Nexus. When comparing individual devices though you really need to look at all of the factors. For example, the S2's screen is 480x800 vs. the Galaxy Nexus at 720x1280. If the Nexus S could already do 60fps for simple UIs on its 480x800, the CPU in the S2's is even better off.

The real important difference between these two screens is just that the Galaxy Nexus has 2.4x as many pixels that need to be drawn as the S2. This means that to achieve the same efficiency at drawing the screen, you need a CPU that can run a single core at 2.4x the speed (and rendering a UI for a single app is essentially not parallelizable, so multiple cores isn't going to save you).

This is where hardware accelerated rendering really becomes important: as the number of pixels goes up, GPUs can generally scale much better to handle them, since they are more specialized at their task. In fact this was the primary incentive for implementing hardware accelerated drawing in Android -- at 720x1280 we are well beyond the point where current ARM CPUs can provide 60fps. (And this is a reason to be careful about making comparisons between the Galaxy Nexus and other devices like the S2 -- if you are running third party apps, there is a good chance today that the app is not enabling hardware acceleration, so your comparison is doing CPU rendering on the Galaxy Nexus which means you almost certainly aren't going to get 60fps out of it, because it needs to hit 2.4x as many pixels as the S2 does.)

To be complete, there is another big advantage that the GPU gives you -- many more drawing effects become feasible. For example, if you are drawing a bitmap in software, you basically can't do anything to it except apply an offset. Just trying to scale it is going to make rendering significantly slower. On a GPU, applying transformations well beyond simple scales is basically free. This is why in the new default Holo themes in Android we have background images -- with hardware accelerated drawing, we can afford to draw (and scale) them. In fact, if the hardware path is not enabled by the app, these background images will be turned off.

Download Image From Url or link in Android With ProgressDialog to Show Image is Loading..

noreply@blogger.com (Himanshu) — Sat, 28 Jan 2012 22:11:00 +0530

Hello,Every One I have Now Write here simple Demo for Loading Image From Url with Help of
AsyncTask in Android,By this Way We Can see that how much data of image has been loading and so we can show progress of Loading Image To ProgressDialog in Android.

Below is Main Activity luncher Class Which is :
LoadBitmapActivity.java

Here is Java Code for It.
___________________________________Start____________________________________________

public class LoadBitmapActivity extends Activity {
/** Called when the activity is first created. */
public boolean isConnected = false;
public static final String IMAGE_URL = "http://media1.santabanta.com/full4/bollywood%20movies/agneepath/agneepath-8a.jpg";
ProgressDialog mProgressDialog;
TextView mTextView;
ImageView mImageView;
Button mButton;
private ByteArrayOutputStream byte_output_stream;
private double filesize;
private double downloaded;
public static final int DOWNLOADING = 0;
private int status = DOWNLOADING;
public static final int COMPLETE = 1;
private Bitmap mBitmap;
HttpURLConnection connection;
InputStream is;
public int MAX_BUFFER_SIZE = 1024;
public static int SIZE = 100;

@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
mTextView = (TextView) findViewById(R.id.text_data);
mImageView = (ImageView) findViewById(R.id.loaded_image);
mButton = (Button) findViewById(R.id.btn_start);
mButton.setOnClickListener(mButtonClickListener);

}

View.OnClickListener mButtonClickListener = new View.OnClickListener() {

@Override
public void onClick(View v) {
switch (v.getId()) {
case R.id.btn_start:
if (checkInternet()) {
new DownloadImagetask().execute(IMAGE_URL);
} else {
AlertDialog.Builder builder = new AlertDialog.Builder(
LoadBitmapActivity.this);
builder.setTitle(R.string.alert_internet_msg_title);

builder.setPositiveButton(R.string.alert_btn_text,
new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog,
int which) {
dialog.dismiss();
}
});
}
break;

default:
break;
}
}
};

public boolean checkInternet() {
ConnectivityManager mConnectivityManager = (ConnectivityManager) this
.getSystemService(Context.CONNECTIVITY_SERVICE);
NetworkInfo mNetworkinfo = mConnectivityManager.getActiveNetworkInfo();
if (mNetworkinfo != null && mNetworkinfo.isAvailable()
&& mNetworkinfo.isConnected()) {
return isConnected = true;
} else {
return isConnected = false;
}
}

private class DownloadImagetask extends AsyncTask<String, Integer, Bitmap> {

@Override
protected void onPostExecute(Bitmap result) {
mProgressDialog.dismiss();
mImageView.setImageBitmap(result);

super.onPostExecute(result);
}

public DownloadImagetask() {
mBitmap = null;
downloaded = 0;
filesize = 0;
status = DOWNLOADING;
}

@Override
protected void onPreExecute() {
mProgressDialog = new ProgressDialog(LoadBitmapActivity.this);
mProgressDialog.setProgressStyle(ProgressDialog.STYLE_HORIZONTAL);
// mProgressDialog.setProgress(0);
mProgressDialog.setMessage(getString(R.string.progress_msg_title));
// mProgressDialog.setMax(10);
mProgressDialog.show();
super.onPreExecute();
}

@Override
protected void onProgressUpdate(Integer... values) {
mProgressDialog.setProgress(values[0]);
super.onProgressUpdate(values);
}

@Override
protected Bitmap doInBackground(String... params) {
try {
URL url = new URL(params[0]);
connection = (HttpURLConnection) url.openConnection();
filesize = connection.getContentLength();
byte_output_stream = new ByteArrayOutputStream((int) filesize);
connection.setDoOutput(true);
connection.connect();
is = connection.getInputStream();

if (filesize < SIZE) {
MAX_BUFFER_SIZE = 1024;
} else {
MAX_BUFFER_SIZE = (int) Math.ceil(filesize / SIZE);
}
// loop with step 1Kb
while (status == DOWNLOADING) {
byte[] imagedata_buffer;
if (filesize - downloaded > MAX_BUFFER_SIZE) {
imagedata_buffer = new byte[MAX_BUFFER_SIZE];
} else {
imagedata_buffer = new byte[(int) (filesize - downloaded)];
}
int read = is.read(imagedata_buffer);
if (read == -1) {
publishProgress(100);
break;
}
byte_output_stream.write(imagedata_buffer, 0, read);
downloaded += read;

publishProgress((int) ((downloaded / filesize) * 100));
}

if (status == DOWNLOADING) {
status = COMPLETE;
}
return BitmapFactory
.decodeStream((InputStream) new ByteArrayInputStream(
byte_output_stream.toByteArray()));

} catch (MalformedURLException excep) {
excep.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
} finally {
if (connection != null) {
connection.disconnect();
}

}

return null;
}

}
}
-----------------------------------------------End of Class------------------------------------------------
Here is Xml that i have used for Activity.

main.xml

<?xml version="1.0" encoding="utf-8"?>
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
   android:layout_width="fill_parent"
   android:layout_height="fill_parent"
   android:layout_gravity="center_vertical" >

   <TextView
   android:id="@+id/text_data"
   android:layout_width="fill_parent"
   android:layout_height="wrap_content"
   android:text="@string/hello" />

   <ImageView
   android:id="@+id/loaded_image"
   android:layout_width="wrap_content"
   android:layout_height="wrap_content"
   android:layout_gravity="center_horizontal"
   android:layout_marginTop="15dip"
   android:src="@drawable/ic_launcher" />

   <Button
   android:id="@+id/btn_start"
   android:layout_width="wrap_content"
   android:layout_height="wrap_content"
   android:layout_gravity="bottom|center_horizontal"
   android:gravity="center"
   android:text="@string/btn_start" />

</FrameLayout>

For Work with image to load from Internet you need to give two permission in your's android project Manifest .And Here are two permission.

This Permission Give us to access internet from our android application.

<uses-permission android:name="android.permission.INTERNET"/>
And Now Second one i have used for To get State of our Android Mobile it is connected to internet or not,and this permission also need to get any changes in network state .
   <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"/>

What is Run Android Lint Checks and What are it's Advantages.

noreply@blogger.com (Himanshu) — Wed, 28 Dec 2011 22:57:00 +0530

For First To Get Advantage for Run Android lint for your Android Project You May Need To Download
Eclipse With Latest Update as Well Android ADT Plugins 16 For use of Lint in Eclipse with out Command Line .

First if you are Using Old Eclipse Like Eclipse Galileo (3.5) and Eclipse Helios (3.6) Then i Prefer You to Use Latest Eclipse Which you can Download From www.Eclipse.org Click Here is Link http://www.eclipse.org/downloads/packages/eclipse-ide-java-developers/indigosr1

After Getting Eclipse Version 3.7 you can Setup Android Application Development Environment By Getting Guide From Below Link:

http://developer.android.com/sdk/installing.html

Check Requirement From Below Link :

http://developer.android.com/sdk/requirements.html

ok now when you Done Will Eclipse Indigo and Set up ADT 16 Plugin and Your Android SDK with it You can see One new Tool in Eclipse that it Run Android lint .Now Let see What is Run Android Lint.

Android Lint is a new tool for ADT 16 (and Tools 16) which scans Android project sources for potential bugs. It is available both as a command line tool, as well as integrated with Eclipse. The architecture is deliberately IDE independent so it will hopefully be integrated with other IDEs, with other build tools and with continuous integration systems as well.

Here are some examples of the types of errors that it looks for:

Missing translations (and unused translations)
Layout performance problems (all the issues the old layoutopt tool used to find, and more)
Unused resources
Inconsistent array sizes (when arrays are defined in multiple configurations)
Accessibility and internationalization problems (hardcoded strings, missing contentDescription, etc)
Icon problems (like missing densities, duplicate icons, wrong sizes, etc)
Usability problems (like not specifying an input type on a text field)
Manifest errors

and many more.

Now Here Are Some Advantages You Will Get to Known When You Run Android Lint for You Android Project .Here are lint Checks .

$ lint --show
Available issues:

Correctness
===========

AdapterViewChildren
-------------------
Summary: Checks that AdapterViews do not define their children in XML

Priority: 10 / 10
Severity: Warning
Category: Correctness

AdapterViews such as ListViews must be configured with data from Java code,
such as a ListAdapter.

More information:

http://developer.android.com/reference/android/widget/AdapterView.html
MissingPrefix
-------------
Summary: Detect XML attributes not using the Android namespace

Priority: 8 / 10
Severity: Warning
Category: Correctness

Most Android views have attributes in the Android namespace. When referencing
these attributes you *must* include the namespace prefix, or your attribute
will be interpreted by aapt as just a custom attribute.

MissingTranslation
------------------
Summary: Checks for incomplete translations where not all strings are
translated

Priority: 8 / 10
Severity: Error
Category: Correctness

If an application has more than one locale, then all the strings declared in
one language should also be translated in all other languages.

By default this detector allows regions of a language to just provide a subset
of the strings and fall back to the standard language strings. You can require
all regions to provide a full translation by setting the environment variable
ANDROID_LINT_COMPLETE_REGIONS.

Proguard
--------
Summary: Looks for problems in proguard.cfg files

Priority: 8 / 10
Severity: Error
Category: Correctness

Using -keepclasseswithmembernames in a proguard.cfg file is not correct; it
can cause some symbols to be renamed which should not be.
Earlier versions of ADT used to create proguard.cfg files with the wrong
format. Instead of -keepclasseswithmembernames use -keepclasseswithmembers,
since the old flags also implies "allow shrinking" which means symbols only
referred to from XML and not Java (such as possibly CustomViews) can get
deleted.

More information: http://code.google.com/p/android/issues/detail?id=16384

ScrollViewCount
---------------
Summary: Checks that ScrollViews have exactly one child widget

Priority: 8 / 10
Severity: Warning
Category: Correctness

ScrollViews can only have one child widget. If you want more children, wrap
them in a container layout.

DuplicateIds
------------
Summary: Checks for duplicate ids within a single layout

Priority: 7 / 10
Severity: Warning
Category: Correctness

Within a layout, id's should be unique since otherwise findViewById() can
return an unexpected view.

InconsistentArrays
------------------
Summary: Checks for inconsistencies in the number of elements in arrays

Priority: 7 / 10
Severity: Warning
Category: Correctness

When an array is translated in a different locale, it should normally have the
same number of elements as the original array. When adding or removing
elements to an array, it is easy to forget to update all the locales, and this
lint warning finds inconsistencies like these.

Note however that there may be cases where you really want to declare a
different number of array items in each configuration (for example where the
array represents available options, and those options differ for different
layout orientations and so on), so use your own judgement to decide if this is
really an error.

You can suppress this error type if it finds false errors in your project.

NestedScrolling
---------------
Summary: Checks whether a scrolling widget has any nested scrolling widgets
within

Priority: 7 / 10
Severity: Warning
Category: Correctness

A scrolling widget such as a ScrollView should not contain any nested
scrolling widgets since this has various usability issues

ScrollViewSize
--------------
Summary: Checks that ScrollViews use wrap_content in scrolling dimension

Priority: 7 / 10
Severity: Warning
Category: Correctness

ScrollView children must set their layout_width or layout_height attributes to
wrap_content rather than fill_parent or match_parent in the scrolling
dimension

DuplicateIncludedIds
--------------------
Summary: Checks for duplicate ids across layouts that are combined with
include tags

Priority: 6 / 10
Severity: Warning
Category: Correctness

It's okay for two independent layouts to use the same ids. However, if layouts
are combined with include tags, then the id's need to be unique within any
chain of included layouts, or Activity#findViewById() can return an unexpected
view.

ExtraTranslation
----------------
Summary: Checks for translations that appear to be unused (no default language
string)

Priority: 6 / 10
Severity: Warning
Category: Correctness

If a string appears in a specific language translation file, but there is no
corresponding string in the default locale, then this string is probably
unused. (It's technically possible that your application is only intended to
run in a specific locale, but it's still a good idea to provide a fallback.)

ManifestOrder
-------------
Summary: Checks for manifest problems like <uses-sdk> after the <application>
tag

Priority: 5 / 10
Severity: Warning
Category: Correctness

The <application> tag should appear after the elements which declare which
version you need, which features you need, which libraries you need, and so
on. In the past there have been subtle bugs (such as themes not getting
applied correctly) when the <application> tag appears before some of these
other elements, so it's best to order your manifest in the logical dependency
order.

StateListReachable
------------------
Summary: Looks for unreachable states in a <selector>

Priority: 5 / 10
Severity: Warning
Category: Correctness

In a selector, only the last child in the state list should omit a state
qualifier. If not, all subsequent items in the list will be ignored since the
given item will match all.

GridLayout
----------
Summary: Checks for potential GridLayout errors like declaring rows and
columns outside the declared grid dimensions

Priority: 4 / 10
Severity: Error
Category: Correctness

Declaring a layout_row or layout_column that falls outside the declared size
of a GridLayout's rowCount or columnCount is usually an unintentional error.

PxUsage
-------
Summary: Looks for use of the "px" dimension

Priority: 2 / 10
Severity: Warning
Category: Correctness

For performance reasons and to keep the code simpler, the Android system uses
pixels as the standard unit for expressing dimension or coordinate values.
That means that the dimensions of a view are always expressed in the code
using pixels, but always based on the current screen density. For instance, if
myView.getWidth() returns 10, the view is 10 pixels wide on the current
screen, but on a device with a higher density screen, the value returned might
be 15. If you use pixel values in your application code to work with bitmaps
that are not pre-scaled for the current screen density, you might need to
scale the pixel values that you use in your code to match the un-scaled bitmap
source.

More information: http://developer.android.com/guide/practices/screens_support.html#screen-independence

Security
========

ExportedService
---------------
Summary: Checks for exported services that do not require permissions

Priority: 5 / 10
Severity: Warning
Category: Security

Exported services (services which either set exported=true or contain an
intent-filter and do not specify exported=false) should define a permission
that an entity must have in order to launch the service or bind to it. Without
this, any application can use this service.

Performance
===========

UseCompoundDrawables
--------------------
Summary: Checks whether the current node can be replaced by a TextView using
compound drawables.

Priority: 6 / 10
Severity: Warning
Category: Performance

A LinearLayout which contains an ImageView and a TextView can be more
efficiently handled as a compound drawable

MergeRootFrame
--------------
Summary: Checks whether a root <FrameLayout> can be replaced with a <merge>
tag

Priority: 4 / 10
Severity: Warning
Category: Performance

If a <FrameLayout> is the root of a layout and does not provide background or
padding etc, it can be replaced with a <merge> tag which is slightly more
efficient.

InefficientWeight
-----------------
Summary: Looks for inefficient weight declarations in LinearLayouts

Priority: 3 / 10
Severity: Warning
Category: Performance

When only a single widget in a LinearLayout defines a weight, it is more
efficient to assign a width/height of 0dp to it since it will absorb all the
remaining space anyway. With a declared width/height of 0dp it does not have
to measure its own size first.

UnusedResources
---------------
Summary: Looks for unused resources

Priority: 3 / 10
Severity: Warning
Category: Performance

Unused resources make applications larger and slow down builds.

LIMITATIONS:
* If you are running lint from the command line instead of Eclipse, then the
analysis of Java files is pattern based rather than using an accurate parse
tree, so the results may not be accurate. (This limitation will go away
soon.)
* The analysis does not consider dependencies between projects, so if you have
a library project which defines resources and a project including the library
project referencing the resources, then the resources will still be reported
as unused.

UselessLeaf
-----------
Summary: Checks whether a leaf layout can be removed.

Priority: 2 / 10
Severity: Warning
Category: Performance

A layout that has no children or no background can often be removed (since it
is invisible) for a flatter and more efficient layout hierarchy.

UselessParent
-------------
Summary: Checks whether a parent layout can be removed.

Priority: 2 / 10
Severity: Warning
Category: Performance

A layout with children that has no siblings, is not a scrollview or a root
layout, and does not have a background, can be removed and have its children
moved directly into the parent for a flatter and more efficient layout
hierarchy.

TooDeepLayout
-------------
Summary: Checks whether a layout hierarchy is too deep

Priority: 1 / 10
Severity: Warning
Category: Performance

Layouts with too much nesting is bad for performance. Consider using a flatter
layout (such as RelativeLayout or GridLayout).The default maximum depth is 10
but can be configured with the environment variable ANDROID_LINT_MAX_DEPTH.

TooManyViews
------------
Summary: Checks whether a layout has too many views

Priority: 1 / 10
Severity: Warning
Category: Performance

Using too many views in a single layout in a layout is bad for performance.
Consider using compound drawables or other tricks for reducing the number of
views in this layout.

The maximum view count defaults to 80 but can be configured with the
environment variable ANDROID_LINT_MAX_VIEW_COUNT.

UnusedIds
---------
Summary: Looks for unused id's

Priority: 1 / 10
Severity: Warning
Category: Performance
NOTE: This issue is disabled by default!
You can enable it by adding --enable UnusedIds

This resource id definition appears not to be needed since it is not
referenced from anywhere. Having id definitions, even if unused, is not
necessarily a bad idea since they make working on layouts and menus easier, so
there is not a strong reason to delete these.

Usability
=========

TextFields
----------
Summary: Looks for text fields missing inputType or hint settings

Priority: 5 / 10
Severity: Warning
Category: Usability

Providing an inputType attribute on a text field improves usability because
depending on the data to be input, optimized keyboards can be shown to the
user (such as just digits and parentheses for a phone number). Similarly,a
hint attribute displays a hint to the user for what is expected in the text
field.

If you really want to keep the text field generic, you can suppress this
warning by setting inputType="text".

Usability:Icons
===============

IconNoDpi
---------
Summary: Finds icons that appear in both a -nodpi folder and a dpi folder

Priority: 7 / 10
Severity: Warning
Category: Usability:Icons

Bitmaps that appear in drawable-nodpi folders will not be scaled by the
Android framework. If a drawable resource of the same name appears *both* in a
-nodpi folder as well as a dpi folder such as drawable-hdpi, then the behavior
is ambiguous and probably not intentional. Delete one or the other, or use
different names for the icons.

GifUsage
--------
Summary: Checks for images using the GIF file format which is discouraged

Priority: 5 / 10
Severity: Warning
Category: Usability:Icons

The .gif file format is discouraged. Consider using .png (preferred) or .jpg
(acceptable) instead.

More information: http://developer.android.com/guide/topics/resources/drawable-resource.html#Bitmap

IconDipSize
-----------
Summary: Ensures that icons across densities provide roughly the same
density-independent size

Priority: 5 / 10
Severity: Warning
Category: Usability:Icons

Checks the all icons which are provided in multiple densities, all compute to
roughly the same density-independent pixel (dip) size. This catches errors
where images are either placed in the wrong folder, or icons are changed to
new sizes but some folders are forgotten.

IconDuplicatesConfig
--------------------
Summary: Finds icons that have identical bitmaps across various configuration
parameters

Priority: 5 / 10
Severity: Warning
Category: Usability:Icons

If an icon is provided under different configuration parameters such as
drawable-hdpi or -v11, they should typically be different. This detector
catches cases where the same icon is provided in different configuration
folder which is usually not intentional.

IconExpectedSize
----------------
Summary: Ensures that launcher icons, notification icons etc have the correct
size

Priority: 5 / 10
Severity: Warning
Category: Usability:Icons
NOTE: This issue is disabled by default!
You can enable it by adding --enable IconExpectedSize

There are predefined sizes (for each density) for launcher icons. You should
follow these conventions to make sure your icons fit in with the overall look
of the platform.

More information: http://developer.android.com/guide/practices/ui_guidelines/icon_design_launcher.html#size

IconLocation
------------
Summary: Ensures that images are not defined in the density-independent
drawable folder

Priority: 5 / 10
Severity: Warning
Category: Usability:Icons

The res/drawable folder is intended for density-independent graphics such as
shapes defined in XML. For bitmaps, move it to drawable-mdpi and consider
providing higher and lower resolution versions in drawable-ldpi, drawable-hdpi
and drawable-xhdpi. If the icon *really* is density independent (for example a
solid color) you can place it in drawable-nodpi.

More information:

IconDensities
-------------
Summary: Ensures that icons provide custom versions for all supported
densities

Priority: 4 / 10
Severity: Warning
Category: Usability:Icons

Icons will look best if a custom version is provided for each of the major
screen density classes (low, medium, high, extra high). This lint check
identifies icons which do not have complete coverage across the densities.

Low density is not really used much anymore, so this check ignores the ldpi
density. To force lint to include it, set the environment variable
ANDROID_LINT_INCLUDE_LDPI=true. For more information on current density usage,
see http://developer.android.com/resources/dashboard/screens.html

More information: http://developer.android.com/guide/practices/screens_support.html

IconDuplicates
--------------
Summary: Finds duplicated icons under different names

Priority: 3 / 10
Severity: Warning
Category: Usability:Icons

If an icon is repeated under different names, you can consolidate and just use
one of the icons and delete the others to make your application smaller.
However, duplicated icons usually are not intentional and can sometimes point
to icons that were accidentally overwritten or accidentally not updated.

IconMissingDensityFolder
------------------------
Summary: Ensures that all the density folders are present

Priority: 3 / 10
Severity: Warning
Category: Usability:Icons

Icons will look best if a custom version is provided for each of the major
screen density classes (low, medium, high, extra high). This lint check
identifies folders which are missing, such as drawable-hdpi.
Low density is not really used much anymore, so this check ignores the ldpi
density. To force lint to include it, set the environment variable
ANDROID_LINT_INCLUDE_LDPI=true. For more information on current density usage,
see http://developer.android.com/resources/dashboard/screens.html

More information: http://developer.android.com/guide/practices/screens_support.html

Accessibility
=============

ContentDescription
------------------
Summary: Ensures that image widgets provide a contentDescription

Priority: 3 / 10
Severity: Warning
Category: Accessibility

Non-textual widgets like ImageViews and ImageButtons should use the
contentDescription attribute to specify a textual description of the widget
such that screen readers and other accessibility tools can adequately describe
the user interface.

Internationalization
====================

HardcodedText
-------------
Summary: Looks for hardcoded text attributes which should be converted to
resource lookup

Priority: 5 / 10
Severity: Warning
Category: Internationalization

Hardcoding text attributes directly in layout files is bad for several
reasons:

* When creating configuration variations (for example for landscape or
portrait)you have to repeat the actual text (and keep it up to date when
making changes)

* The application cannot be translated to other languages by just adding new
translations for existing string resources.