My Adventures in Android Development

Changing Tab with Horizontal Swipe Gesture

2012-05-31T08:01:00.000-07:00

This tutorial describes the code I used to change activities with a swipe or fling gesture. This is an update to my scrolling tab article.

Lets say you want right and left "swipes" or "flings" to be able to flip through the tabs, like pages in a book.

In my project, I am using tabs that have separate activities to fill the content views.

As far as I can tell, the gesture can be detected two ways: place the gesture listener in each activity or from just this one to control them all. I placed code that handles swipes in the main activity page, the one that contains the set up for the tab host, and also sets the content for all the tabs.

Here is what you add to the main java file:

public class GestureScrollTabActivity extends TabActivity implements OnClickListener {

static TabHost mTabHost;
Intent intent;
private static final int SWIPE_MIN_DISTANCE = 120;
private static final int SWIPE_MAX_OFF_PATH = 250;
private static final int SWIPE_THRESHOLD_VELOCITY = 200;
private GestureDetector gestureDetector;
View.OnTouchListener gestureListener;

/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);

[...]

// Gesture detection
gestureDetector = new GestureDetector(new MyGestureDetector());
gestureListener = new View.OnTouchListener() {
public boolean onTouch(View v, MotionEvent event) {
return gestureDetector.onTouchEvent(event);
}
};
mTabHost.setOnClickListener(GestureScrollTabActivity.this);
mTabHost.setOnTouchListener(gestureListener);

} // end onCreate

[...]

class MyGestureDetector extends SimpleOnGestureListener {
@Override
public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX, float velocityY) {
try {
if (Math.abs(e1.getY() - e2.getY()) > SWIPE_MAX_OFF_PATH)
return false;
// right to left swipe
if (e1.getX() - e2.getX() > SWIPE_MIN_DISTANCE && Math.abs(velocityX) > SWIPE_THRESHOLD_VELOCITY) {
int i = mTabHost.getCurrentTab();
mTabHost.setCurrentTab(i+1);
Toast.makeText(GestureScrollTabActivity.this, "Left Swipe", Toast.LENGTH_SHORT).show();
} else if (e2.getX() - e1.getX() > SWIPE_MIN_DISTANCE && Math.abs(velocityX) > SWIPE_THRESHOLD_VELOCITY) {
int i = mTabHost.getCurrentTab();
mTabHost.setCurrentTab(i-1);
Toast.makeText(GestureScrollTabActivity.this, "Right Swipe", Toast.LENGTH_SHORT).show();
}
} catch (Exception e) {
// nothing
}
return false;
}
}

@Override
public void onClick(View v) {
Filter f = (Filter) v.getTag();
// FilterFullscreenActivity.show(this, input, f);
// Toast.makeText(GestureScrollTabActivity.this, "onClick", Toast.LENGTH_SHORT).show();
}

}

Resources:
(1) http://stackoverflow.com/questions/937313/android-basic-gesture-detection

Reading a TXT File from the Emulator's "SD Card"

2012-01-20T09:10:00.000-08:00

The app that I'm developing has to read a TXT file from an SD card storage and display it in textview.

The process to get your file (any file) onto the emulator's pretend SD card is kind of tricky. First you have to create the SD card. I did this in eclipse by opening the AVD manager, selecting the device you want to create the SD card in and clicking edit.

In the edit screen, find the SD Card section and give your SD card a side. I gave mine 4 GB.

Then you have to move your file onto the SD card. In eclipse, this can be done by running your app and opening the DDMS view. Go to the File Explorer tab. Expand the "mnt" folder. Select the "sdcard" folder. Once selected, select the button in the upper right that has an image on a phone and an arrow. This should read "Push a file onto the device" when you hover over it. Click it. Find the file on your hard drive and push that baby onto the phone. Whew. Now its available to be read by our app.

Back to java. I pulled this code from someone's awesome answer on StackOverflow but forgot to bookmark it. Sorry!

// Find the directory for the SD Card using the API
// *Don't* hardcode "/sdcard"
File sdcard = Environment.getExternalStorageDirectory();

// Get the text file
File file = new File(sdcard, "filename.txt");

// Read text from file
StringBuilder text = new StringBuilder();
try {
BufferedReader br = new BufferedReader(new FileReader(file));
String line;

while ((line = br.readLine()) != null) {
text.append(line);
text.append('\n');
}
} catch (IOException e) {
// You'll need to add proper error handling here
}
DialogDetails.setText( text );

How to View Your Android App Database: SQLite Database Broswer

2012-01-13T09:23:00.000-08:00

I've been using SQLite Database Browser to look through my android database and make changes. Linky link:

http://sourceforge.net/projects/sqlitebrowser/

You can pull your application's database off the emulator as a .sql file and open it up in this browser to see all that fancy sql stuff.

To get your database off the emulator:

First, you have to have eclipse open and running, and run your application in your emulator of choice.

Once the app is up and running, go back to eclipse and select Window > Open Perspective > DDMS

Under the Devices tab: Make sure the emulator that is running your app is highlighted/selected. Navigate to the "File Explorer" tab. (If it's not available, select Window > Show View > File Explorer.)

In the File Explorer tab: (1) open the "data" folder, (2) open a second "data" folder, (3) find and open the folder with "your application's name", (4) find and open the "databases" folder, (5) select the file with your application's name

In the upper right of the File Explorer frame, there is a button with an image of a floppy disk with an arrow. Click on the one that says "Pull a file from device" and save your database file somewhere memorable. It might automatically save it to your project's location on your hard drive.

Now you can view it and play around with it in SQLite Database Browser :)

Keep in mind that you have to upload the new database onto the phone or emulator before the changes can be accessed by your app.

Custom Tabs that Scroll Horizontally

2011-07-05T09:19:00.000-07:00

So I designed horizontally scrolling tabs that use separate activities to fill the tab content. TI rate this a 1/5 on the fun scale: there are so many different files you have to create and different selection states you have to consider. (Click here for my update to this tutorial: Changing Tab with Horizontal Swipe Gesture)

Faded edges indicate additional content

tabhostlayout.xml - Pretty basic stuff here, if you followed the tab widget tutorial on the android dev site.[1] The only thing to note here is that I surrounded the tab widget with Horizontal Scroll View element to achieve a horizontal scroll for the tabs. (Note: Sorry for the formatting here. I've tried to fix it only to make it much much worse. Blame blogger?)

<TabHost
xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@android:id/tabhost"
android:layout_width="fill_parent"
android:layout_height="fill_parent">
<LinearLayout
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent">
<HorizontalScrollView
android:layout_width="fill_parent"
android:layout_height="wrap_content">
<TabWidget
android:id="@android:id/tabs"
android:layout_width="fill_parent"
android:layout_height="wrap_content" />
</HorizontalScrollView>
<FrameLayout
android:id="@android:id/tabcontent"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:padding="5dp" />
</LinearLayout>
</TabHost>

TabHostActivity.java - This activity must extend TabActivity. You will need to define the following variables and also set the divider drawable BEFORE setting up tabs

TabHost mTabHost = (TabHost) findViewById(android.R.id.tabhost);
mTabHost.getTabWidget().setDividerDrawable(R.drawable.tab_divider);
Intent intent; // Reusable Intent for each tab

For each tab you would like to add, use the following code in onCreate:

intent = new Intent().setClass(TabHostActivity.this, PageOne.class);
setupTab(new TextView(this), "Tab One", intent);

After onCreate, you need to add two new classes. "setupTab" creates the tabs and tab content. "createTabView" handles all tab events, like setting the views for selection events and stuff like that.

private void setupTab(final View view, final String tag, final Intent myIntent) {
View tabview = createTabView(mTabHost.getContext(), tag);
TabSpec setContent = mTabHost.newTabSpec(tag).setIndicator(tabview).setContent(myIntent);
mTabHost.addTab(setContent);
}
private static View createTabView(final Context context, final String text) {
View view = LayoutInflater.from(context).inflate(R.layout.tabs_bg, null);
TextView tv = (TextView) view.findViewById(R.id.tabsText);
tv.setText(text);
return view;
}

tabs_bg.xml - In the code above, "createTabView" calls a layout called tabs_bg. Create this file in the layout folder. This layout creates the layout for each tab element. I have only added a single textview but an image view could also be added (but will need some adjustments to the java code not shown above). This is where some of the layout personalization comes in. Text size and style, and padding elements. Note the background and text color call drawable files that handle the color changes for selection events.

<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/tabsLayout"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:background="@drawable/tab_bg_selector"
android:padding="3dip"
android:gravity="center"
android:orientation="vertical">
<TextView
android:layout_width="wrap_content"
android:textColor="@drawable/tab_text_selector"
android:gravity="center"
android:textSize="12dip"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:id="@+id/tabsText"
android:text="Title"
android:padding="10px">
</TextView>
</LinearLayout>

tab_bg_selector.xml - both bg and text selector drawable files require the same four states to be defined: active, pressed, selected (using arrows), and inactive. I don't really know why the text and bg have to be separate files, but when I tried to combine them, it wasn't displaying properly. This code resembles custom button selection.

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


<item
android:state_selected="true"
android:state_focused="false"
android:state_pressed="false">
<shape
android:shape="rectangle">
<gradient
android:startColor="#A8A8A8"
android:centerColor="#7F7F7F"
android:endColor="#696969"
android:angle="-90" />
</shape>
</item>



<item
android:state_selected="false"
android:state_focused="false"
android:state_pressed="false">
<shape
android:shape="rectangle">
<gradient
android:startColor="#5C5C5C"
android:centerColor="#424242"
android:endColor="#222222"
android:angle="-90" />
</shape>
</item>

<item
android:state_pressed="true"
android:drawable="@android:color/transparent" />

<item
android:state_selected="true"
android:state_focused="true"
android:state_pressed="false"
android:drawable="@android:color/transparent" />
</selector>

tab_text_selector.xml

<selector
xmlns:android="http://schemas.android.com/apk/res/android">
<item
android:state_selected="true"
android:color="@android:color/white" />
<item
android:state_focused="true"
android:color="@android:color/white" />
<item
android:state_pressed="true"
android:color="@android:color/white" />

<item
android:color="#f8f8f8" />
</selector>

References:
1) http://developer.android.com/resources/tutorials/views/hello-tabwidget.html
2)http://joshclemm.com/blog/?p=136
For additional help, click here to download a zip containing all the files needed to create the above project.

Solution to "Installation error: INSTALL_FAILED_INSUFFICIENT_STORAGE"

2011-07-01T10:50:00.000-07:00

Source: http://stackoverflow.com/questions/4709137/solution-android-install-failed-insufficient-storage-error

Getting this error:

[2011-07-01 10:36:22 - MDatHand] Installation error: INSTALL_FAILED_INSUFFICIENT_STORAGE
[2011-07-01 10:36:22 - MDatHand] Please check logcat output for more details.
[2011-07-01 10:36:22 - MDatHand] Launch canceled!

I used this solution:

RIGHT CLICK the root of your Android Project
SELECT "Run As" then go to "Run Configurations..."
LOCATE the "Android Application" node in the tree at the left then SELECT your project
SELECT "Target" tab on the right side of the window look down for the "Additional Emulator Command Line Options" field (sometimes you'll need to make the window larger)
PASTE "-partition-size 1024" there
CLICK "Apply" and then Run to use your emulator

Like so.

“Debug certificate expired” Error in Eclipse

2011-06-23T12:31:00.000-07:00

When there is no error in the code, but for some reason the project says there is an error and prevents you from running...

When you've torn your hair out trying to delete and re-import your project files to no avail...

When you've "cleaned" and "fixed project properties" so many times your index fingertip is bleeding...

Try looking at your project problems ( Window > Show View > Problems )

You might get something that looks like this:
Debug Certificate Expired...

If the above has happened to you, then I have a fix for you! You can probably solve this problem by deleting the debug certificate file. (Eclipse will then build a new one, and the error will go away.)

Win 7 OS: Go to ( Window > Preferences > Android > Build ) and find out where the debug.keystore file is located on your hard drive. Then using file explorer, find it and destroy it.

Thats it. Import your projects or whatever, do a clean and the error should disappear.

References:
http://stackoverflow.com/questions/2194808/debug-certificate-expired-error-in-eclipse-android-plugins

So you need to change the text size of simple_list_item_single_choice...

2011-06-08T13:41:00.000-07:00

I feel you.

I tried for a month straight to call the checkedtextview in the android standard layout and resize the text. It never let me. I felt like a idiot. And now that I've figured it out, I know that it is more than just a feeling.

And so I'm posting it here, in the event that I actually forget how to do this later on. Because.. you know... I'm an idiot.

I went and copied the xml from the api demo and pasted it into a new .xml file(step 1). I accessed the text size and adjusted it thusly (step 2). Then I changed the java code to replace the simple_list_item_single_choice with my own custom row layout (step 3). Facepalmed for about two hours (step 4).

my_listitem_singlechoice.xml (i just chaged "textAppearance" attribute but I'm sure you can do other stuff to it too) :

<CheckedTextView xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@android:id/text1"
android:layout_width="match_parent"
android:layout_height="?android:attr/listPreferredItemHeight"
android:textAppearance="?android:attr/textAppearanceSmall"
android:gravity="center_vertical"
android:checkMark="?android:attr/listChoiceIndicatorSingle"
android:paddingLeft="6dip"
android:paddingRight="6dip"
/>

my_java_with_singlechoice.java (this should look somewhat familiar) :

ListView lv = this.getListView();
MyListAdapter = new ArrayAdapter<String>(this, R.layout.my_listitem_singlechoice, myArrayList);
lv.setAdapter(MyListAdapter );
lv.setChoiceMode(ListView.CHOICE_MODE_SINGLE);

Getting Your Big Ass Database onto Your Android Phone

2011-04-27T10:42:00.000-07:00

Yeah, I effing did it!!!!!!!!!! (Sorry, still pumped from finally getting this to work.)

First off: giving credit where credit is due. Many many many thanks to my sources:

http://www.reigndesign.com/blog/using-your-own-sqlite-database-in-android-applications/

http://www.mail-archive.com/android-developers@googlegroups.com/msg28194.html

http://www.chriskopec.com/blog/2010/mar/13/deploying-android-apps-with-large-databases/

My project requires a preformed database (SQLite), which in total comes out to a whopping 17mb. Ridiculous I know, but my boss wants it all packaged with the app, and not just to be available online. Hypothetically, getting this to work should be as easy as creating a blank db and then copying the existing one over it from assets or raw. And this totally works-- if your db is smaller than 1mb. So I went and got some free file splitting software (http://www.dekabyte.com/filesplitter/) and split my db file into 1mb pieces. I put the pieces in the raw directory.

I created the DataBaseHelper class and made the necessary tweaks:

public class DataBaseHelper extends SQLiteOpenHelper {

// The Android's default system path of your application database.
private static final String DB_PATH = "/data/data/com.instacare/databases/";

private static final String DB_NAME = "MDAtHand";

private SQLiteDatabase myDataBase;

private final Context myContext;
Resources resources;

/**
* Constructor Takes and keeps a reference of the passed context in order to
* access to the application assets and resources.
*
* @param context
*/
public DataBaseHelper(Context context) {

super(context, DB_NAME, null, 1);
this.myContext = context;

// super(context, DB_NAME, null, 1);
resources = context.getResources();
}

/**
* Creates a empty database on the system and rewrites it with your own
* database.
* */
public void createDataBase() throws IOException {

boolean dbExist = checkDataBase();

if (dbExist) {
// do nothing - database already exist

copyDataBase();

} else {

// By calling this method and empty database will be created into
// the default system path
// of your application so we are gonna be able to overwrite that
// database with our database.
this.getReadableDatabase();

try {

copyDataBase();

} catch (IOException e) {

throw new Error("Error copying database");

}
}

}

/**
* Check if the database already exist to avoid re-copying the file each
* time you open the application.
*
* @return true if it exists, false if it doesn't
*/
private boolean checkDataBase() {

SQLiteDatabase checkDB = null;

try {
String myPath = DB_PATH + DB_NAME;
checkDB = SQLiteDatabase.openDatabase(myPath, null,
SQLiteDatabase.OPEN_READONLY);

} catch (SQLiteException e) {

// database does't exist yet.

}

if (checkDB != null) {

checkDB.close();

}

return checkDB != null ? true : false;
}

/**
* Copies your database from your local assets-folder to the just created
* empty database in the system folder, from where it can be accessed and
* handled. This is done by transfering bytestream.
* */
private void copyDataBase() throws IOException {

// Open your local db as the input stream
// InputStream myInput = myContext.getAssets().open(DB_NAME);

// Path to the just created empty db
// String outFileName = DB_PATH + DB_NAME;

// Open the empty db as the output stream
// OutputStream myOutput = new FileOutputStream(outFileName);

// transfer bytes from the inputfile to the outputfile
// byte[] buffer = new byte[1024];
// int length;
// while ((length = myInput.read(buffer))>0){
// myOutput.write(buffer, 0, length);
// }

// Close the streams
// myOutput.flush();
// myOutput.close();
// myInput.close();

InputStream databaseInput = null;
// String outFileName = DB_PATH + DbConsts.DATABASE_NAME;
String outFileName = DB_PATH + DB_NAME;
OutputStream databaseOutput = new FileOutputStream(outFileName);

byte[] buffer = new byte[1024];
int length;

databaseInput = resources.openRawResource(R.raw.datafile01);
while ((length = databaseInput.read(buffer)) > 0) {
databaseOutput.write(buffer, 0, length);
databaseOutput.flush();
}
databaseInput.close();
databaseInput = resources.openRawResource(R.raw.datafile02);
while((length = databaseInput.read(buffer)) > 0) {
databaseOutput.write(buffer, 0, length);
databaseOutput.flush();
}
databaseInput.close();
databaseInput = resources.openRawResource(R.raw.datafile03);
while((length = databaseInput.read(buffer)) > 0) {
databaseOutput.write(buffer, 0, length);
databaseOutput.flush();
}
databaseInput.close();

databaseInput = resources.openRawResource(R.raw.datafile04);
while((length = databaseInput.read(buffer)) > 0) {
databaseOutput.write(buffer, 0, length);
databaseOutput.flush();
}
databaseInput.close();
databaseInput = resources.openRawResource(R.raw.datafile05);
while((length = databaseInput.read(buffer)) > 0) {
databaseOutput.write(buffer, 0, length);
databaseOutput.flush();
}
databaseInput.close();
databaseInput = resources.openRawResource(R.raw.datafile06);
while((length = databaseInput.read(buffer)) > 0) {
databaseOutput.write(buffer, 0, length);
databaseOutput.flush();
}
databaseInput.close();
databaseInput = resources.openRawResource(R.raw.datafile07);
while((length = databaseInput.read(buffer)) > 0) {
databaseOutput.write(buffer, 0, length);
databaseOutput.flush();
}
databaseInput.close();
databaseInput = resources.openRawResource(R.raw.datafile08);
while((length = databaseInput.read(buffer)) > 0) {
databaseOutput.write(buffer, 0, length);
databaseOutput.flush();
}
databaseInput.close();
databaseInput = resources.openRawResource(R.raw.datafile09);
while((length = databaseInput.read(buffer)) > 0) {
databaseOutput.write(buffer, 0, length);
databaseOutput.flush();
}
databaseInput.close();
databaseInput = resources.openRawResource(R.raw.datafile10);
while((length = databaseInput.read(buffer)) > 0) {
databaseOutput.write(buffer, 0, length);
databaseOutput.flush();
}
databaseInput.close();
databaseInput = resources.openRawResource(R.raw.datafile11);
while((length = databaseInput.read(buffer)) > 0) {
databaseOutput.write(buffer, 0, length);
databaseOutput.flush();
}
databaseInput.close();
databaseInput = resources.openRawResource(R.raw.datafile12);
while((length = databaseInput.read(buffer)) > 0) {
databaseOutput.write(buffer, 0, length);
databaseOutput.flush();
}
databaseInput.close();
databaseInput = resources.openRawResource(R.raw.datafile13);
while((length = databaseInput.read(buffer)) > 0) {
databaseOutput.write(buffer, 0, length);
databaseOutput.flush();
}
databaseInput.close();
databaseInput = resources.openRawResource(R.raw.datafile14);
while((length = databaseInput.read(buffer)) > 0) {
databaseOutput.write(buffer, 0, length);
databaseOutput.flush();
}
databaseInput.close();
databaseInput = resources.openRawResource(R.raw.datafile15);
while((length = databaseInput.read(buffer)) > 0) {
databaseOutput.write(buffer, 0, length);
databaseOutput.flush();
}
databaseInput.close();
databaseInput = resources.openRawResource(R.raw.datafile16);
while((length = databaseInput.read(buffer)) > 0) {
databaseOutput.write(buffer, 0, length);
databaseOutput.flush();
}
databaseInput.close();
databaseInput = resources.openRawResource(R.raw.datafile17);
while((length = databaseInput.read(buffer)) > 0) {
databaseOutput.write(buffer, 0, length);
databaseOutput.flush();
}
databaseInput.close();
databaseOutput.flush();
databaseOutput.close();

}

public void openDataBase() throws SQLException {

// Open the database
String myPath = DB_PATH + DB_NAME;
myDataBase = SQLiteDatabase.openDatabase(myPath, null,
SQLiteDatabase.OPEN_READONLY);

}

@Override
public synchronized void close() {

if (myDataBase != null)
myDataBase.close();

super.close();

}

@Override
public void onCreate(SQLiteDatabase db) {

}

@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {

}

// Add your public helper methods to access and get content from the
// database.
// You could return cursors by doing "return myDataBase.query(....)" so it'd
// be easy
// to you to create adapters for your views.

}

Then I added this awesomeness to the main.java file

DataBaseHelper myDbHelper = new DataBaseHelper(this);
   //myDbHelper = new DataBaseHelper(this);

   try {

   myDbHelper.createDataBase();

} catch (IOException ioe) {

throw new Error("Unable to create database");

}

try {

myDbHelper.openDataBase();

}catch(SQLException sqle){

throw sqle;

}

Thats it :)

Deleting Single Choice Listview Items

2011-02-09T07:41:00.000-08:00

This post assumes you know how to create a single choice listview and a button in xml.

1) First, define these three variables:

   public static List<String> strings;
   public static ListAdapter adapter;
   ListView lv;

2) Next, set up the listview in onCreate:

   strings = new ArrayList<String>();
   lv = getListView();
   adapter = new ArrayAdapter<String>(this,android.R.layout.simple_list_item_single_choice, strings);
   lv.setChoiceMode(ListView.CHOICE_MODE_SINGLE);
   lv.setAdapter(adapter);

3) Last, set up the delete button:

   Button btnRemove = (Button) findViewById(R.id.ButtonEditLabOrderForm_Remove);
   btnRemove.setOnClickListener(new View.OnClickListener() {
   @SuppressWarnings("unchecked")
   public void onClick(View v) {
   // Code below only works with ONE CHECKED ITEM at a time
   int len = lv.getCount();
SparseBooleanArray checked = lv.getCheckedItemPositions();
for (int i = 0; i < len; i++)
if (checked.get(i)) {
String item = strings.get(i);
// do whatever you want with the checked item
strings.remove(item);
((ArrayAdapter<String>) adapter).notifyDataSetChanged();
}
   }
   });

Thats it !

Still trying to figure out how to delete multiple items in a multiple choice list :(

Button with Image and Text

2011-02-01T12:37:00.000-08:00

This all goes down in the XML file with the button in question. This can also be accomplished dynamically (not shown.) Here is the excerpt from the xml file defining the button. The image should be located in the drawable folder. The image is called from android:drawable. Use drawableLeft, drawableRight, drawableTop, drawableBottom depending on how you want to place the image in relation to the text. Adjust the padding to suit your aesthetic.

<Button
   android:layout_width="wrap_content"
   android:text="Sample Text"
   android:id="@+id/Button01"
   android:layout_height="wrap_content"
   android:drawableLeft="@drawable/search"
   android:drawablePadding="0px"
   android:padding="0px">
</Button>

Custom Spinner Row Layout & Custom Spinner Adapter

2011-01-28T09:01:00.000-08:00

The custom spinner adapter is similar to the custom list row & adapter, because we can use LayoutInflater.

(*edit: This code may not run as-is. Therefore, I have included project files associated with this post available for download at the end of this post.)

1) The spinner layout. This is how each row will look when the spinner is selected. In my example there are three text views as three rows.

<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent" android:orientation="vertical">
<TextView
android:layout_height="wrap_content"
android:id="@+id/TextView01"
android:textSize="12px"
android:layout_width="match_parent"
android:textColor="#000000">
</TextView>
<TextView
android:layout_height="wrap_content"
android:id="@+id/TextView02"
android:layout_width="match_parent"
android:textSize="12px" android:textColor="#000000"></TextView>
<TextView
android:layout_height="wrap_content"
android:id="@+id/TextView03"
android:layout_width="match_parent"
android:textSize="12px"
android:textColor="#000000">
</TextView>
</LinearLayout>

2) The custom adapter

// CUSTOM SPINNER ADAPTER
public class MyCustomSpinnerAdapter extends ArrayAdapter<String> {

public MyCustomSpinnerAdapter(Context context, int textViewResourceId,
String[] objects) {
super(context, textViewResourceId, objects);
// TODO Auto-generated constructor stub
}

@Override
public View getDropDownView(int position, View convertView, ViewGroup parent) {
// TODO Auto-generated method stub
return getCustomView(position, convertView, parent);
}

@Override
public View getView(int position, View convertView, ViewGroup parent) {
// TODO Auto-generated method stub
return getCustomView(position, convertView, parent);
}

public View getCustomView(int position, View convertView,ViewGroup parent) {
// TODO Auto-generated method stub
// return super.getView(position, convertView, parent);

LayoutInflater inflater = getLayoutInflater();

ViewHolder holder;
if (convertView == null) {
convertView = inflater.inflate(R.layout.customspinneritem, null);
holder = new ViewHolder();
holder.txt01 = (TextView) convertView.findViewById(R.id.TextView01);
holder.txt02 = (TextView) convertView.findViewById(R.id.TextView02);
holder.txt03 = (TextView) convertView.findViewById(R.id.TextView03);

convertView.setTag(holder);

} else {

holder = (ViewHolder) convertView.getTag();
}

holder.txt01.setText("Route")
holder.txt02.setText("Strength");
holder.txt03.setText("Form");

return convertView;
}

class ViewHolder {
TextView txt01;
TextView txt02;
TextView txt03;
}

} // end custom adapter

3) Calling the spinner & setting the adapter

Spinner spinner = (Spinner) findViewById(R.id.spinner1);
spinner.setPrompt("Select One");
spinner.setAdapter(new MyCustomSpinnerAdapter(this, 0, items));
spinner.setOnItemSelectedListener(new OnItemSelectedListener() {
@Override
public void onItemSelected(AdapterView<?> parentView, View selectedItemView, int position, long id) {
// your code here
}

@Override
>public void onNothingSelected(AdapterView<?> parentView) {
// your code here
}
});

4) Setting string items

String[] items = { "Route 1, Strength 1, Form 1", "Route 2, Strength 2, Form 2", "Route 3, Strength 3, Form 3" };

Downloads:
main.xml
customspinneritem.xml
CustomSpinnerActivity.java (select "qui")

Resources:
My previous Spinner post
Android Dev Tutorial - Hello Spinner
Custom List Row Layout w/ Adapter

Simple Spinner w/ Array Adapter

2011-01-28T08:13:00.000-08:00

Very basic stuff here, people. If you haven't yet, get acquainted with android spinner using the dev tutorial.

1) Calling the spinner, defining the array adapter.

   Spinner spinner= (Spinner) findViewById(R.id.spinner);
   ArrayAdapter<String> spinnerArrayAdapter = new ArrayAdapter<String>(
   this, android.R.layout.simple_spinner_item, items);
   spinnerArrayAdapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
     spinner.setPrompt("Select One");
     spinner.setAdapter(spinnerArrayAdapter );
spnRoute.setOnItemSelectedListener(new OnItemSelectedListener() {
@Override
public void onItemSelected(AdapterView<?> parentView,
View selectedItemView, int position, long id) {
// your code here
}

@Override
public void onNothingSelected(AdapterView<?> parentView) {
// your code here
}
});

2) The string array

String[] items = { "lorem", "ipsum", "dolor", "sit", "amet"};

Seriously, this is how I made a multi-column list item populated by strings!!

2011-01-14T10:37:00.000-08:00

Untitled Document 1) The item layout:

<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/LinearLayout01"
android:layout_alignParentLeft="true"
android:layout_height="fill_parent"
android:orientation="vertical"
android:layout_width="fill_parent">
<TextView
android:layout_height="wrap_content"
android:id="@+id/TextView_Title"
android:text="Title"
android:textSize="15px"
android:layout_width="fill_parent"></TextView>

<LinearLayout
android:id="@+id/LinearLayout02"
android:layout_width="fill_parent"
android:layout_height="wrap_content">
<TextView
android:layout_height="wrap_content"
android:id="@+id/TextView_Item1"
android:text="Item1"
android:layout_width="wrap_content"
android:textSize="10px" android:layout_weight="1"/>
<TextView
android:layout_height="wrap_content"
android:id="@+id/TextView_Item2"
android:text="Item2"
android:layout_width="wrap_content"
android:textSize="10px" android:layout_weight="1"/>
<TextView
android:layout_height="wrap_content"
android:id="@+id/TextView_Item3"
android:text="Item3"
android:layout_width="wrap_content"
android:textSize="10px" android:layout_weight="1"/>
</LinearLayout>
</LinearLayout>

2) Build the custom adapter:

// CUSTOM TWO ROW LIST ADAPTER
static class EfficientAdapter extends BaseAdapter {
private LayoutInflater mInflater;

public EfficientAdapter(Context context) {
mInflater = LayoutInflater.from(context);
}

public int getCount() {
return title.size();
}

public Object getItem(int position) {
return position;
}

public long getItemId(int position) {
return position;
}

public View getView(int position, View convertView, ViewGroup parent) {
ViewHolder holder;
if (convertView == null) {
convertView = mInflater.inflate(R.layout.listitem_addrx, null);
holder = new ViewHolder();
holder.txtTitle = (TextView) convertView.findViewById(R.id.TextView_Title);
holder.txtItem1 = (TextView) convertView.findViewById(R.id.TextView_Item1);
holder.txtItem2 = (TextView) convertView.findViewById(R.id.TextView_Item2);
holder.txtItem3 = (TextView) convertView.findViewById(R.id.TextView_Item3);

convertView.setTag(holder);
holder = (ViewHolder) convertView.getTag();
}

holder.txtTitle.setText(title.get(position));
holder.txtItem1.setText(one.get(position));
holder.txtItem2.setText(two.get(position));
holder.txtItem3.setText(three.get(position));

return convertView;
}

static class ViewHolder {
TextView txtTitle;
TextView txtItem1;
TextView txtItem2;
TextView txtItem3;
}
} // end custom adapter

3) Call the following items:

static ListView lv;
public static ListAdapter adapter;
String selected;
static final ArrayList<String> title = new ArrayList<String>();
static final ArrayList<String> one = new ArrayList<String>();
static final ArrayList<String> two = new ArrayList<String>();
static final ArrayList<String> three = new ArrayList<String>();

4) Set the list adapter:

lv = (ListView) getListView();
lv.setAdapter(new EfficientAdapter(this));

5) Add entries to list:

Either define a string array when you call the variables in step 3 or add items dynamically:

title.add(selected);
route.add(selected);
strength.add(selected);
form.add(selected);

lv.setAdapter(new EfficientAdapter(getBaseContext()));

References (& many, many thanks to):

Custom list row & adapter: http://www.androidpeople.com/android-custom-dynamic-listview/

Custom spinner row & adapter: http://android-er.blogspot.com/2010/12/custom-arrayadapter-for-spinner-with.html

Update with my version later...

Custom Button Using XML

2011-01-14T10:33:00.000-08:00

1. Create a custombuttonlayout.xml file in the drawable folder

Selector: this element surrounds the entire xml. It defines this drawable as a selecter (e.g. buttons, list rows, or anything that can be "selected")

Items: There are three buttons states that must be defined: pressed, focused, normal. However, there are a total of seven states that can be defined(pressed, focused, selected, checkable, checked, enabled, and window_focused).These are defined as three separate "items". Due to the nature of the way java programs are read (basically from the top down) you need to define items in this specific order, with pressed first, focused next, and normal last to get the buttons to display correctly.

Gradient: Android buttons typically have a highlight/lowlight gradient, so you should define two colors, and the angle of the "shadow".

Stroke: I think this defines the outline style of the button? Not too sure...

Corners: creates a rounded button corner. The default android radius value is "5dp".

Padding: This defines the blank space between the button text and the button borders.

custombuttonlayout.xml

<selector
  xmlns:android="http://schemas.android.com/apk/res/android">
  <item
   android:state_pressed="true">
   <shape>
   <gradient
   android:startColor="#FFFF40"
   android:endColor="#FFFFC0"
   android:angle="270" />
   <stroke
   android:width="1dp"
   android:color="#000000" />
   <corners
   android:radius="5dp" />
   <padding
   android:left="10dp"
   android:top="15dp"
   android:right="10dp"
   android:bottom="15dp" />
   </shape>
  </item>
  <item
   android:state_focused="true">
   <shape>
   <gradient
   android:endColor="#8080FF"
   android:startColor="#C0C0C0"
   android:angle="270" />
   <stroke
   android:width="1dp"
   android:color="#4A494A" />
   <corners
   android:radius="5dp" />
   <padding
   android:left="10dp"
   android:top="15dp"
   android:right="10dp"
   android:bottom="15dp" />
   </shape>
  </item>
  <item>
   <shape>
   <gradient
   android:endColor="#8080FF"
   android:startColor="#C0C0C0"
   android:angle="270" />
   <stroke
   android:width="1dp"
   android:color="#000000" />
   <corners
   android:radius="5dp" />
   <padding
   android:left="10dp"
   android:top="15dp"
   android:right="10dp"
   android:bottom="15dp" />
   </shape>
  </item>
</selector>

2. In the main.xml layout when you insert a button that you want to apply the layout to:

Define the button background source as the drawable/custombuttonlayout.xml from above.

excerpt from main.xml:

<Button
   android:layout_width="wrap_content"
   android:text="Sample Text"
   android:id="@+id/Button01"
   android:layout_height="wrap_content"
   android:background="@drawable/custombuttonlayout"></Button>

Resources:

1) http://developer.android.com/guide/topics/resources/drawable-resource.html#StateList

2) http://developer.android.com/guide/topics/resources/color-list-resource.html

3) http://developer.android.com/reference/android/widget/Button.html

4) http://androiddrawableexplorer.appspot.com/

5) http://developer.android.com/guide/topics/resources/drawable-resource.html#Shape

Date Picker Frustrations

2010-12-13T09:20:00.000-08:00

The date picker for the scheduler part of my app has somehow completely disappeared from existence. Did I dream that this was a working widget and never bothered to try it out in real life!? Anyhow, I'm trying to implement a date picker from an options menu click event inside a tabhost and the code is giving me a load of problems. Damn you, ambiguously written android dev tutorial!

The result -- I think trying to implement a date picker in tabhost is impossible. Something about the content view... had to work around the problem by adding a "select a date" button into the activity controlling that particular tab and removing the troublesome item from the options menu.

Saving State on Orientation Change

2010-12-03T13:50:00.000-08:00

Problem:

Form loses state on orientation change. This is due to onCreate being called on orientation change. This affects pages with forms half-filled out becoming blank.

Solution:

In Manifest.xml, go to Application tab, select the Activity in question (yes, you have to do this for EVERY activity you want to protect). For Config Changes select “keyboardHidden” and “orientation”. Worked for me.

Repainting a ListView Adapter from a Separate Activity

2010-12-03T13:46:00.000-08:00

Basically, I have a page with a search box. You search for something, get the results in the form of a list on a pop-up dialog (which has its own activity). When you select one of the results, the dialog closes, and the item is added to the original page with the search box. You can repeat this, ad nauseum. *NOTE* This method requires an API level of at least 1.6.

PageOne.java
Be sure to declare variables for the strings and adapter before onCreate. Static makes it available to use by other activities in the package:

static List<String> strings; ListView lv; static ListAdapter adapter;

Define these variables inside onCreate:

strings = new ArrayList<String>();
lv = getListView();
adapter = new ArrayAdapter<String>(this, R.layout.list_item, R.id.label, strings);
lv.setAdapter(adapter);

PageTwo.java

In the onClick method, add code to transform selected item to a string value. Then, adds the item to the String Array in PageOne. Last, notifyDataSetChanged on the adapter used in pageone:

@Override
public void onListItemClick(ListView parent, View v, int position, long id) {
selected = ((TextView) v).getText().toString();
PageOne.strings.add(selected);
((ArrayAdapter<String>) PageOne.adapter).notifyDataSetChanged();
this.finish();
}

"Conversion to Dalvik format failed with error 1"

2010-12-02T10:37:00.000-08:00

Ugh. Don't you hate errors that aren't in the code, and don't go away no matter how many times you fix project setup or clean.

Heres what I got in the console:

[2010-12-02 10:38:10 - MDatHand]
trouble processing "java/lang/Object.class":
[2010-12-02 10:38:10 - MDatHand]
Attempt to include a core VM class in something other than a core library.
It is likely that you have attempted to include the core library from a desktop
virtual machine into an application, which will most assuredly not work. If
you really intend to build a core library -- which is only appropriate as
part of creating a full virtual machine binary, as opposed to compiling an
application -- then use the "--core-library" option to suppress this error
message. If you go ahead and use "--core-library" but are in fact building
an application, then please be aware that your build will still fail at some
point; you will simply be denied the pleasure of reading this helpful error
message.
[2010-12-02 10:38:10 - MDatHand] 1 error; aborting
[2010-12-02 10:38:10 - MDatHand] Conversion to Dalvik format failed with error 1

Oh yeah... this was certainly a real pleasure... jerk. The only thing I understand in all that garbage is "library" not that that give me any damn clue on how to fix it. How but just a nice error message that says "FIX YOUR LIBRARY SETTINGS"????? Anywho, I digress...

I did some soul searching on the interwebs, and a nice man by the name of Jim had posted a reasonable solution. I'm posting it herein the event the error pops up again again:

I received the following message and found several others who had seen
it but no solution. So I have included how I finally fixed it. (I'm
using Eclipse version 3.4.2 and Android 1.5.)

...
The fix for me was to go to my project's properties, select:

Java Build Path -> Libraries (tab)

Somehow, the android.jar had been added, and when I deleted it, all
was good. Note that the android.jar is included as part of the
Android 1.5 library, so this was a duplication.

How did this happen? I certainly didn't do it. But my app has blown
up a lot in the emulator, so who knows.

Later . . . Jim

THANKS JIM :]

Marquee Attributes

2010-11-30T08:10:00.000-08:00

This has absolutely nothing to do with Android or Java.

I had a text marquee announcement news thingy on my company website, and I didn't want to lose the code because it took me a full day to figure out how to use marquee attributes.

<marquee behavior="scroll" direction="left" scollamount="1" onmouseover="this.stop();" onmouseout="this.start();"></marquee>

Setting up Android Development Environment with Eclipse

2010-11-26T21:47:00.000-08:00

I've done set up a fifth computer with the Android Dev environment and every time it's a gorram struggle. I hate setting up workstations! So here I am, finally conceding to the idea that there will never be a last and final time for the most tedious, time consuming, and confusing chores.

1) Download Eclipse IDE for Java Developers 3.5 (Galileo). The newer version 3.6 Helios is not supported by android. Galileo comes as a zip file, no install necessary. Unzip somewhere you will remember, and make shortcuts to your desktop/task bar/whatever.
http://www.eclipse.org/downloads/packages/eclipse-ide-java-developers/galileor

2) Download JDK/JRE v.6 (or the new v.7). Follow the install. You will need a login username and password for Sun Microsystems. (*Optional: After install, find the jdk folder, and copy the "jre" file into your eclipse folder. I don't know if this is the correct way to do this, but it works for me. Particularly useful if you downloaded the Android SDK as a zip rather than the installer.)
http://www.oracle.com/technetwork/java/javase/downloads/index.html

3) Download Android SDK. This can also come as a zip file but also includes an installer which I will recommend, because the installer will "link" the Android SDK to the JDK. Whatever that means. But because of this linking thing, the JDK has to be fully installed first in order to run.
http://developer.android.com/sdk/index.html

4) Add SDK Platform. After the installer from step 3 finishes, start the SDK program. Start checking off stuff to add. You need at least ONE platform to begin developing in android. You will need to download all the versions you plan on testing on. Be sure to add packages in small groups, if you try to do it all at once it crashes or never finishes.

http://developer.android.com/sdk/adding-components.html

5) "Download"/Install/Configure ADT plugin. Finish downloading the SDK in step 4 before attempting this. Adding the ADT to Eclipse requires use of the "Adding new software" option from the Help menu. Its awful and feels wrong. Instructions at the link below. Be sure to follow the steps for downloading AND configuring the ADT plugin!

http://developer.android.com/sdk/eclipse-adt.html#downloading

6) Create an AVD (Android Virtual Device.) This is the emulator. I set the target to Android 2.2 - API Level 8, and the skin to WVGA854
http://developer.android.com/guide/developing/tools/avd.html#creating

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

Adding xml Layout to an Existing xml Layout Dynamically

2010-11-18T13:07:00.000-08:00

So some background information is needed for this tutorial. My project requires many many many screens. It's incredibly difficult to keep track of all these for development purposes, and on top of that it makes load time on the phone mind-bogglingly slow. So I am trying to create generic "blank" screens to use and reuse for my applications. In this particular example, I have created a generic list screen with a TextView "title" and a blank ListView. I already know that I can programically change the row styling, data entries, the text in the title, etc etc. But I needed to add a row of buttons to the bottom. So I created a simple xml layout with some buttons inside a horizontal linear layout. This is where I hit the snag. I assumed it would be simple to just say mainlayout.addView(extrabuttonslayout);

I was wrong.

So after three or four days of searching, attempting, failing... (Yeah I know I'm slow) I magically discovered four magical lines of text that allow me to make all my wildest dreams come true. At least for now.

So here's how I did it:

main.xml

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

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

android:orientation="vertical" android:layout_height="fill_parent"

android:layout_width="fill_parent" android:id="@+id/LinearLayout_listview">

<TextView android:layout_height="wrap_content"

android:layout_width="fill_parent" android:text="title" android:id="@+id/TextView_Title"

android:padding="5px" android:textSize="20px" />

<ListView android:layout_height="wrap_content" android:id="@android:id/list"

android:layout_width="fill_parent" android:layout_weight="1" />

<FrameLayout android:layout_height="wrap_content"

android:id="@+id/FrameLayout_listview" android:layout_width="fill_parent" />

</LinearLayout>

extrabuttonlayout.xml

<LinearLayout android:layout_height="wrap_content" android:layout_width="fill_parent"
android:gravity="center" android:id="@+id/LinearLayout_er">
<Button android:layout_width="wrap_content"
android:layout_height="wrap_content" android:text="Search"
android:minWidth="100px" android:id="@+id/btnEmergencyResponse_Search"></Button>
<Button android:layout_width="wrap_content"
android:layout_height="wrap_content" android:text="Exit"
android:minWidth="100px" android:id="@+id/btnEmergencyResponse_Exit"></Button>
</LinearLayout>

and finally the oh so dynamic MainActivity.java (I only included the part where I dynamically add a view, for info on how to dynamically populate a listview, or handle click evens, see my other entries.) Basically here we are setting our layout to be a "view" and then adding the view to the main layout. Silly me, I already thought it was a view...

public class MainActivity extends ListActivity {

LayoutInflater linflater;
LinearLayout llList;
LinearLayout llER;

/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);

//trying to add view to listview.xml
llList = (LinearLayout) findViewById(R.id.LinearLayout_listview);
   linflater = (LayoutInflater) getSystemService(Context.LAYOUT_INFLATER_SERVICE);
   View myView = linflater.inflate(R.layout.extrabuttonlayout, null);
   llList.addView(myView);

}
}

Using Intent and Bundle to pass String values to a new Activity.

2010-10-13T10:50:00.000-07:00

So it took me three days to figure out how to pass on a string value from an old activity to a new one. This version uses bundle and intent.

I have only used this when starting a new activity with a button , list item , and menu item clicks events, although I'm sure it can be applied to many more types.

You will need two activities. My example uses a list item click to set up a regular intent. A bundle is created with a string value, and its variables are ("unique.key.name", "The string you want to pass on"). (items[position]) is code that displays the text value of the list item that was selected. Then the bundle is added to the intent.

Page1.java

public void onListItemClick(ListView parent, View view, int position, long id) {
Intent i = new Intent(Page1.this, Page2.class);
Bundle extras = new Bundle();
extras.putString("my.unique.extras.key", (items[position]) + " Details");
i.putExtras(extras);
startActivity(i);
}

Page2 activity needs to have a textview item ready to receive the bundle (this would look like uniquetextview.setText(extras.getString("("my.unique.extras.key")). An alternative is to set the bundle to be the activities title, as in my example below.

Page2.java

// Adds selected listview item to title

Bundle extras = this.getIntent().getExtras();

if ( extras != null ) {

if ( extras.containsKey("my.unique.extras.key") ) {

this.setTitle(extras.getString("my.unique.extras.key"));

}

Easy ListView with Anchored Header/Footer and "Custom" Row Layout.

2010-10-07T09:08:00.000-07:00

This is the basic listview that has been working great for me.

Disclaimer: While the list item view for this is "custom" it does not allow you to provide more than one view per list item. You can customize that one item (background, font, size, color, etc.) To add more views to a list item please see my entry on custom list adapters.

First is the page layout. I only included a simple textview header, but it could easily be replaced with buttons or checkboxes or anything. The surrounding linear layout but be set to "fill_parent" height and width and also have a vertical orientation. The listview width should be set to "fill_parent" so that the whole list row is clickable and not just the text. layout_weight should be set to 1 which will cause the listview to expand to the height of available space in the window, pushing the header or footer to be docked at the top or bottom.

pageone.xml

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

  android:layout_height="fill_parent"
  android:layout_width="fill_parent"
  android:orientation="vertical" >

<TextView android:layout_height="wrap_content"
  android:layout_width="fill_parent"
  android:text="This is the Header"
  android:id="@+id/Header" >
</TextView>

<ListView
  android:layout_width="fill_parent"
  android:layout_height="wrap_content"
  android:layout_weight="1"
  android:textFilterEnabled="true"
  android:id="@android:id/list" >
</ListView>
</LinearLayout>

The row layout is important if you want to customize the look of your list (like text size, color, etc). Otherwise, android has some built in layouts that can be used. In my example, I am just using a single textview (easily populated by string values using simpleadapter) with a small font. Add more textviews in a horizontal linear layout for columns, or vertical for two rows of text. Use relative layout to add photos and for even more customization. Remember the id of the textviews that will be populated by simple adapter later on. (EDIT: If you want to use additional text views, image views check boxes or whatever, you need to use a custom adapter!)

list_item.xml

<TextView xmlns:android="http://schemas.android.com/apk/res/android"
  android:layout_width="fill_parent"
  android:layout_height="fill_parent"
  android:padding="10dp"
  android:textSize="16sp"
  android:id="@+id/label">
</TextView>

In the java file, include a String of the items you want to display before the onCreate. Set the list Adapter in onCreate. Set up list item click event handler after onCreate. Right now, it is set up to display a toast message of the list item selected.

PageOne.java

public class StepTherapy extends ListActivity {

String[] items={"lorem", "ipsum", "dolor", "sit", "amet",
"consectetuer", "adipiscing", "elit", "morbi", "vel",
"ligula", "vitae", "arcu", "aliquet", "mollis",
"etiam", "vel", "erat", "placerat", "ante",
"porttitor", "sodales", "pellentesque", "augue",
"purus"};
   /** Called when the activity is first created. */
   @Override
   public void onCreate(Bundle savedInstanceState) {
   super.onCreate(savedInstanceState);
   setContentView(R.layout.steptherapy);

ListView lv = (ListView)getListView();
   lv.setAdapter(new ArrayAdapter<String>(this, R.layout.list_item, R.id.label, items));
   public void onListItemClick(ListView parent, View v, int position, long id) {
   Toast.makeText(getApplicationContext(), ((TextView) v).getText(), Toast.LENGTH_SHORT).show();
}
}

Easy Tab Layout using separate Activities to fill Tab Content.

2010-10-04T13:59:00.001-07:00

This is the working tab layout that I have designed thus far. This project requires three xml layouts, two xml drawables and a three java classes (and two png drawables for tab logos).

The main.xml file should have the following. Elements like buttons or TextViews that are needed to be displayed outside of the tabs or tab window should be placed above or below TabHost. Use the include method to add tab content layout files.

main.xml

<TabHost

   xmlns:android="http://schemas.android.com/apk/res/android"
  android:id="@android:id/tabhost"
  android:layout_width="fill_parent"
  android:layout_height="fill_parent"
  android:isScrollContainer="true">

<LinearLayout android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent">

<TabWidget android:id="@android:id/tabs"
android:layout_width="fill_parent"
android:layout_height="wrap_content">
</TabWidget>

<FrameLayout android:id="@android:id/tabcontent"
android:layout_width="fill_parent"
android:layout_height="fill_parent"></FrameLayout>

</LinearLayout>
</TabHost>

I'm only going to include two tabs. You need to have a separate layout.xml file for each tab's content.

tab1.xml and tab2.xml (they are the same for the sake of this tutorial)

<LinearLayout
  xmlns:android="http://schemas.android.com/apk/res/android"
  android:id="@+id/scheduler_dayview"
  android:layout_height="fill_parent"
  android:layout_width="fill_parent"
  android:orientation="vertical">

<TextView android:layout_width="fill_parent"
  android:text="Tab 1"
  android:padding="5px"
  android:id="@+id/TextView01"
  android:layout_height="wrap_content"
</TextView>

</LinearLayout>
Again, for the sake of this tutorial, the tabs respective activities are the same.

Tab1.java and Tab2.java

public class Tab1 extends Activity {

/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.tab1);

}

}

Now for the java class.

TabLayoutExample.Java

public class TabLayoutExample extends TabActivity {

   // Called when the activity is first created.
   @Override
   public void onCreate(Bundle savedInstanceState) {
   super.onCreate(savedInstanceState);
   setContentView(R.layout.main);

   // Tab Stuff
   Resources res = getResources();
   TabHost tabHost = getTabHost();
   Intent intent;

   // Create an Intent to launch an Activity for the tab
   intent = new Intent().setClass(this, Tab1.class);
   // Initialize a TabSpec for each tab and add it to the TabHost
   tabHost.addTab(tabHost.newTabSpec("t1").setIndicator("Tab1",
   res.getDrawable(R.drawable.tab1))
   .setContent(intent));

   // Do the same for the other tabs
   intent = new Intent().setClass(this, Tab2.class);
   tabHost.addTab(tabHost.newTabSpec("t2").setIndicator("Tab2",
   res.getDrawable(R.drawable.tab2))
   .setContent(intent));

   tabHost.setCurrentTab(0);
   }
}