C#Wave.NET

Local storage with SQLite for Hybrid Mobile App with IONIC, Cordova and sqlite

2015-05-24T01:05:00.000-07:00

After hours of search on google there was no proper documentation on how to implement step by step instructions to implement local storage for hybrid mobile application.

This post will help you implement the feature without searching multiple locations for instructions.

1) Create a IONIC or Cordova basic application using command line

Cordova based app

Cordova create localStoreApp

IONIC based app

ionic start localStoreApp

2) Add the ios platform to the application

cd localStoreApp

cordova platform add ios

ioinc platform add ios

3) Build the basic app to check cli is correctly building

cordova build ios

ionic build ios

4) Add sqlite plugin

cordova plugin add https://github.com/litehelpers/cordova-sqlite-common

5) Add the plugin to the config.xml file in the current directory,

under the setting <access origin="*"/>

6) If local storage is not required to be backed up on iCloud,

Under the settings <platform name="ios">

7) Copy the SQLitePlugin.js file under the directory

plugins / cordova-sqlite-common/www/

SQLitePlugin.js

8) Past the copied file into the current locations www/js directory

9) Refer the SQLitePlugin.js file from the index.html file.

Reference should be below cordova.js file

10) Access the databased on where it needs to be used.

sqlite should be accessed after the deviceready event in Cordova and $ionicPlatform.ready call back in IONIC.

var db = window.sqlitePlugin.openDatabase("Database", "1.0", "Demo", -1);

db.transaction(function(tx) {

tx.executeSql('DROP TABLE IF EXISTS test_table');

tx.executeSql('CREATE TABLE IF NOT EXISTS test_table (id integer primary key, data text, data_num integer)');

alert("DB droped")

tx.executeSql("INSERT INTO test_table (data, data_num) VALUES (?,?)", ["test", 100], function(tx, res) {

console.log("insertId: " + res.insertId + " -- probably 1");

//alert("rowsAffected: " + res.rowsAffected + " -- should be 1");

alert("Data Inserted")

tx.executeSql("select count(id) as cnt from test_table;", [], function(tx, res) {

console.log(("res.rows.length: " + res.rows.length + " -- should be 1");

console.log(("res.rows.item(0).cnt: " + res.rows.item(0).cnt + " -- should be 1");

alert("Data Selected")

});

tx.executeSql("select data from test_table;", [], function(tx, res) {

console.log(("res.rows.length: " + res.rows.length + " -- should be 1");

alert("res.rows.item(0) :" + res.rows.item(0).data );

alert("Data Selected")

});

}, function(e) {

alert("ERROR: " + e.message);

});

11) Build and Prepare the application for platform

cordova build ios

ionic build ios

12) run the application using the cli command or via the xcode

cli - cordova run ios --device

ionic run ios --device

xcode - navigate the the folder

platforms / ios

open the file localstoreapp.xcodeproj

run the application by clicking on play button or product menu > run

Kindly let me know if you encounter any build error or if the application does not get deployed correctly.

Suppose if the application does get built but not correctly gets deployed then remove the platform and add it. remember to run the prepare ios command which will download the necessary files needed for ios.

Happy coding

Creating HTML 5 based android Mobile App with cordova (PhoneGap)

2014-04-08T21:05:00.000-07:00

This article covers the steps followed to successfully create the first PhoneGap based Android Application.

Follow the steps as per the given order bellow

Pre-requests
Installing Apache ANT
Installing Eclipse
Adding Android ADT Plugin
Installing NodeJS
Installing Cordova
Setting up Environment Variable
Creating Cordova App

1. Pre-requests

Confirm Java is installed on your machine.

eg: Open command prompt and type Java. You should see a screen similar to bellow.

If Java is not installed you should be able to download from below location.

https://www.java.com/en/download/

2. Installing Apache ANT

Apache ANT can be found in below location

https://ant.apache.org/bindownload.cgi

download the highlighted file and open the zip file. Open the extracted folder and copy the ant folder to c:/ folder.

3. Installing Eclipse

Download Eclipse from below location.

https://www.eclipse.org/downloads/packages/eclipse-standard-432/keplersr2

Extract the ZIP file and copy the Eclipse to c:/Program Files location

4. Adding Android ADT Plugin

Steps to add Plugin

Open Eclipse

Click on Help

Follow as per the screen shots

Click on Add

Type as per the screen.
Name : ADT Plugin
Location: https://dl-ssl.google.com/android/eclipse/

Select the check boxes as per the screen

Agree the licences for all and click on finish.

It would take quite a long time to download and install the ADT.

5. Installing NodeJS

Download NodeJS from below location.

http://nodejs.org/download/

6. Installing cordova

Open NodeJS command prompt which is in All Programs as shown below.

Once the command prompt is open type below command
npm install cordova

7.Setting up Environment Variables

All the system environment variables are listed below with name and value pair. If you find any of them are missing create them under system environment variables.

The locations are as per my machine and you need to find the correct location as per your installation.

Set up ANT_HOME path in user variables

If you don't find ANT_HOME in your user variables create New one as per instructions below

Click on NEW button under user variables and type these values.

Variable : ANT_HOME

Value : c:\ant (remember ant was extracted and copied to c: root directory)

Set up ANDROID_ADT_PATH in system variable

If you don't find ANDROID_NDK_PATH in your system variables create New one as per instructions below

Click on NEW button under system variables and type these values.

Variable : ANDROID_NDK_PATH

Value : C:\Users\UDXF001\Documents\Android\ndk\android-ndk-r8d (by default when the ADT Plugin is installed via eclipse it will put under the users documents.)

Set up PATH in system variable

Select path under the system variables. Click on Edit and copy the variable content in Variable value.

Past the content in a new notepad.

Check if nodejs is correctly installed by searching for nodeJS in the content. If it does not exist then you need to install the nodejs as per the instructions given on top. Expected path should be C:\Program Files\nodejs\;

Add the ANT bin path by typing C:\ant\bin\; (again location based on where it is...)

Add android sdk paths as per below given values.

C:\Software\adt-bundle-windows-x86_64-20131030\sdk\platform-tools;

C:\Software\adt-bundle-windows-x86_64-20131030\sdk\tools;

to find the location search for adt-bundle-windows in the file explorer and replace it with your own location.

Once the above settings are changed copy the hole content, delete the content in variable value and past it there.

Next restart the PC and since all are good to go.

We will create our first application in the next step and emulate it.

8. Creating cordova android based app

follow the instructions highlighted in yellow step by step

Once the Build Success is displayed the android emulator will prompt and this would take quite a while.

You will be able to see an app similar to this which means you are good to go to the next steps.

I will be writing my next Blog on how to work with Aptana Studio to create apps which is more user friendly to work with HTML apps.

Please give your feedback on this so that it would help me and others to improve. Raise your questions if you find any steps failing. Most likely on step 8 you will encounter some issue like http://stackoverflow.com/questions/22626338/unable-to-resolve-phone-gap-error-cmd-command-failed-with-exit-code-enoent-3

and my answer to that is http://stackoverflow.com/questions/22312332/phone-gap-error-cmd-command-failed-with-exit-code-enoent/22952259#22952259

Happy Codeing :)

C# Searching Data form DataTable does not work as expected

2013-12-08T19:50:00.000-08:00

An XML file was loaded to the datatable and performed a search for the member id as shown bellow. For a few it was returning records and for the few while the data exists it did not return the data.

string path = WebConfigurationManager.AppSettings.Get("xmlFilePath");
if (path.Length > 0)
{
ds.ReadXml(path);
if (ds.Tables.Count > 0)
{
DataRow[] result = ds.Tables[0].Select(
string.Format("member_id={0}", memberID));
if (result.Length > 0)
{
lblCardNumber.Text = result[0]["card_no"].ToString();
lblPointsBalance.Text = result[0]["closing_balance"].ToString();
}
}
}

The reason being member_id column was a string column and if the change was as shown below it did return the data.

DataRow[] result = ds.Tables[0].Select(
string.Format("member_id='{0}'", memberID));

I am yet to find the reason for this issue. The correct way to find the string value is to add (') before and after the value.

ASP.NET MVC Structure Map, No parameter less constructor defined for this object.

2013-10-27T03:20:00.000-07:00

While using Structure Map with ASP.NET MVC there was a error "No parameter less constructor defined for this object" for the already working controller.

[HttpPost]
        public ActionResult CreateBranch(mBranch branch)
        {
            _service.CreateBranch(branch);

            return new JsonResult { Data = "Registered", JsonRequestBehavior = JsonRequestBehavior.AllowGet };
        }

The Structure map Controller factory were configured properly and once this method is commented everything working except when this post method was called the error was thrown.

Reason why it threw the exception was that the class mBranch had only once constructor with a parameter when the method is called mBranch is instantiated it there was no constructor without parameter and resulted in this error.

public class mBranch
    {
        public mBranch(int companyId)
        {
            CompanyID = companyId;
            BranchContact = new mContactInfo();
        }

             //error thrown due to this constructor was missing
        public mBranch()
        {
            BranchContact = new mContactInfo();
        }
    }

Editing a macro which automatically open and close after the macro runs

2013-10-01T05:53:00.003-07:00

I spend hours trying to edit my macro which when opened it will run the macro and create a separate file and then closes by it self.

Thanks for this post to same my time.

http://www.excelforum.com/excel-new-users-basics/881031-cant-edit-macro-with-auto-open-and-auto-close.html

All you need to do is to

Open the excel application
Go to File
Go to Open
Pres on Shift Button
Then select the macro file
Go to view
Select the view macro to see the code

Multiple foreign keys within same table using CodeFrist Enitty Framework and Fluent API

2013-06-07T20:42:00.003-07:00

This example shows how to work with multiple foreign key referred to the same table using CodeFirst Entity Framework (Inverse Navigation Properties
)

Parent Table (Branch) has two foreign keys (Primary Contact and Secondary Contact) referring to the Child Table (Contact).

Branch
BranchID	guid
Branch Name	varchar
PrimaryContactID	guid,null
SecondaryContatID	guid,null

Contact
ContactID	guid
Firstname	varchar
LastName	varchar
Address	varchar
Gender	char

First of all we need to create the Branch Class

public class Branch

{

public Guid BranchID { get; set; }

public string BranchName { get; set; }

public Nullable<Guid> PrimaryContactID { get; set; }

public Nullable<Guid> ScondaryContactID{ get; set; }

public Contact PrimaryContact { get; set; }

public Contact SecondaryContact { get; set; }

}

Then creating the Contact Class

public class Contact

{

public Guid ContactID { get; set; }

public string Firstname { get; set; }

public string Lastname { get; set; } public ICollection<Branch> PrimaryContactFor { get; set; }

public ICollection<Branch> ScondaryContactFor{ get; set; }

}

When configuring in the fluent API below shown coding is used.

protected override void OnModelCreating(DbModelBuilder modelBuilder)
{
base.OnModelCreating(modelBuilder);
modelBuilder.Entity<Branch>().HasOptional(b => b.PrimaryContact).WithMany(a => a.PrimaryContactFor).HasForeignKey(b=>b.PrimaryContactID);
modelBuilder.Entity<Branch>().HasOptional(b => b.SecondaryContact).With Many (a => a.ScondaryContactFor).HasForeignKey(b=>b.ScondaryContactID);

}

Happy Coding :)

Shortcut Keys in Visual Studio Editor

2013-05-08T20:25:00.000-07:00

Some Useful Visual Studio shortcut keys

I would like to share some on the shortcut keys that are available in visual studio that will be very useful for the developers for fast codeing. I have segregated them into different parts.

VS Tools and Explore Bars (Windows) Related

Solution Explorer	Ctrl +W, S
Server Explorer	Ctrl + W, L
Error List	Ctrl + W, E
Output Window	Ctrl + W, O
Property Window	Ctrl + W, P
Tool Box	Ctrl + W, X

Code File Related

Comment Selection	Ctrl +E, C or Ctrl + K, C
Uncomment Selection	Ctrl + E, U or Ctrl + K, U
Format Document	Ctrl + E, D
Make UPPERCASE	Ctrl + Shit, U
Make lowercase	Ctrl + U
Place Bookmark	Ctrl + B + E
Clear Bookmark	Ctrl + B + C
Toggle Bookmark	Ctrl + B + T
Previous Bookmark	Ctrl + B + P
Next Bookmark	Ctrl + B + N

Project Related

Add New Class	Shift + Alt + C
Add New Item	Ctrl + Shift + A
Add Existing Item	Shift + Alt + A

I use these shortcuts daily in my coding life and makes my life easy and fast to code. Hope this will effect your coding life and i would like to hear your feedback on this and please suggest if you have any.

Your feedbacks are warmly welcomed.

Happy Coding :)

ASP.NET MVC Call multiple collection parameter action method from AJAX

2013-04-05T01:23:00.002-07:00

Call multiple collection parameter action method using AJAX
This example is used to demonstrate how to send multiple collection data to a action method in MVC.
First i have defined the View Model which is the type of the collection that is used as the parameter of the action method.
Second the Controller Action Method is defined to show that it takes to List<Employee> collections.
Third listing explains the View - javascript which stringify the object and send a AJAX request to the server.
View Model
public class Employee
{
public int ID{get;set;}
public string Name{get;set;}
public string Age{get;set;}
}

Controller Action Method

public ActionResult SaveData(List<Employee> updateEmployee, List<Employee> deleteEmployee)
{
try
{
   //Do your processing
}
catch(exception)
{
   // do your loggin
}
}

View - javascript
$(document).ready(function(){
// Here i would like to simulate the collections by adding them statically for simplicity
var uEmployee = new Object();
var dEmployee = new Object();
//Create update employees
var ut1Emp = new Object();
ut1Emp.ID = 1; ut1Emp.Name="Desmond"; ut1Emp.Age="27";
var ut2Emp = new Object();
ut2Emp.ID = 2; ut2Emp.Name="Maria"; ut2Emp.Age="1";
uEmployee.Push(ut1Emp );
uEmployee.Push(ut2Emp );
//Create delete employees
var dt1Emp = new Object();
dt1Emp.ID = 3; dt1Emp.Name="Jacintha"; dt1Emp.Age="25";
var dt2Emp = new Object();
dt2Emp.ID = 4; dt2Emp.Name="Angel"; dt2Emp.Age="1";
dEmployee.Push(dt1Emp );
dEmployee.Push(dt2Emp );

var param = { 'updateEmployee': uEmployee, 'deleteEmployee': dEmployee};

$.ajax({ url: "SaveData",
          type: 'POST',
          contentType: "application/json; charset=utf-8" , // this is important
          data: JSON.stringify(param), // This is important
          failure: function (errorMSG){
              alert('Error occurred on saving data');
          },
          success: function (data) {
          alert('Successfully saved');
          }
        });
});

Keyword 'this' is not valid in a static property, static method, or static field initializer this.Page.User.Identity.Name

2012-07-08T19:30:00.000-07:00

[WebMethod] is static and if the User.Identity.Name is used this error "Keyword 'this' is not valid in a static property, static method, or static field initializer" is thrown.

Reason being this.Page.User.Identity is non static and usage is not valid.

Instead using " HttpContext.Current.User.Identity.Name " will resolve the error since current is static.

ex:
someVariable = someMethodArgument(HttpContext.Current.User.Identity.Name);

How to win Interviews

2012-02-10T17:32:00.000-08:00

I would like to share my experience to those who face the interviews.

Look at the roles and responsibility of the job
Basic overview of the employer on what is their main business, achievements and products or service they provide
Be there at least 20 minutes earlier
While facing the interview be open and honest
If you don't know the straight answer say you don't know but think logically and try to find possible way, tell your interviewer this way it should happen (Reason we are not born in this world with full of knowledge, important is to think instantly what could be the possible solution)
When you are asked about some coding solution, think about the solution and while explaining tell them the answer and the steps to achieve the answer. Very important if you have implemented smiler solution in the past please refer
Be friendly and don't get panic if you dont know the answer.

When you learn new technology learn the basic concepts through an ebook or product web site like MSDN

Good luck guys i will update this when things get into my memory. Best luck for your future...

Single or multiple Image upload on ASP.NET MVC3

2012-01-13T16:37:00.000-08:00

I spent a great time searching for an example of Upload Image on ASP.NET MVC3 web site.

These are the two simple steps you need to do. (single image)

Create the view
---------------------

<form action="" method="post" enctype="multipart/form-data">
<input type="text" name="firstName" id="firstName" />
<input type="file" name="file" id="file1" />
<input type="submit" />

*Note - Make sure the name that you give for the input type file is important

or If u are using html helper to create the form

@using (Html.BeginForm("Upload", "Home", FormMethod.Post, new { enctype = "multipart/form-data" }))
{
<input type="text" name="firstName" id="firstName" />
<input type="file" name="file" id="file1" />
<input type="submit" />
}

Create the controller

[HttpPost]

public ActionResult Upload(string firstName, HttpPostedFileBase file)

{

if (file.ContentLength > 0)

{

using(Image img= Image.FromStream(file.InputStream))

{

//--Initialize the size of the array

byte[] imgData = new byte[file.InputStream.Length];

//--Create a new BinaryReader and set the InputStream

//-- for the Images InputStream to the

//--beginning, as we create the img using a stream.

BinaryReader reader = new BinaryReader(file.InputStream);

file.InputStream.Seek(0, SeekOrigin.Begin);

//--Load the image binary.

imgData = reader.ReadBytes((int)file.InputStream.Length);

//--Create a new image to be added to the database

}

return RedirectToAction("Index");

}

For multiple Image upload

The View

<form action="" method="post" enctype="multipart/form-data">
<input type="text" name="firstName" id="firstName" />
<input type="file" name="files" id="file1" />
<input type="file" name="files" id="file2" />
<input type="submit" />

or If u are using html helper to create the form

@using (Html.BeginForm("Upload", "Home", FormMethod.Post, new { enctype = "multipart/form-data" }))
{
<input type="text" name="firstName" id="firstName" />
<input type="file" name="files" id="file1" />
<input type="file" name="files" id="file2" />
<input type="submit" />
}

The Controller

[HttpPost]
public ActionResult Upload(string firstName, IEnumerable<HttpPostedFileBase> files)
{
foreach (var file in files)
{
if (file.ContentLength > 0)
{
using(Image img= Image.FromStream(file.InputStream))
{
//--Initialize the size of the array
byte[] imgData = new byte[file.InputStream.Length];

//--Create a new BinaryReader and set the InputStream
//-- for the Images InputStream to the
//--beginning, as we create the img using a stream.
BinaryReader reader = new BinaryReader(file.InputStream);
file.InputStream.Seek(0, SeekOrigin.Begin);

//--Load the image binary.
imgData = reader.ReadBytes((int)file.InputStream.Length);

//--Create a new image to be added to the database
}
}
}
return RedirectToAction("Index");
}

Reference
http://garfbradazweb.wordpress.com/2011/08/16/mvc-3-upload-sql-server-entity-framework/

Unable to load one or more of the requested types. Retrieve the LoaderExceptions property for more information.

2011-12-11T16:51:00.001-08:00

Problem :
When i created the MVC3 project while having the Domain on a separate project and reffed the dll to the web project i came across this error "Unable to load one or more of the requested types. Retrieve the LoaderExceptions property for more information."

Solution:
Remove the reference to the Entity Framework dll and add the Entity Framework dll on the domain bin project again.

Reason :
When i started the web project i added reference to EF 4.1 but while completing the domain i refereed to EF 4.2. This was the cause to the problem.

:) coding

Problem Installing MVC 3

2011-10-10T09:46:00.000-07:00

Warning Message
"This product is incompatible with the Microsoft Visual Studio Async CTP. Please uninstall the component, then try to install this product again"

Solution
Go to Control Panel -> Click on View Installed Updates -> Under Microsoft Visual Studio 2010 Ultimate or type Async in search box and then -> select the Microsoft Visual Studio Async CTP and Uninstall.

About Me

2011-10-10T09:38:00.000-07:00

Dear Readers,

I welcome you all to my very first blog with a warm welcome. I would like to give you brief introduction about myself so that it I can stay one step closer to you. I am from Sri Lanka the beautiful isle of the Indian Ocean. I have completed my Masters Degree in Computer Science and I have more than 5 years of experience in Software Development.

I started with classic ASP, developed a web based CRM for call center after one year I moved to another company where I worked for another year on ASP.net and Oracle 9i and developed an ERP system. I could not find what I was looking for there as well, but the moment I went to the Interview at Duo Software, I was much happy and excited to join them.

At Duo I developed the CRM with customized fields, Campaign Manager, Soft Phone using Microsoft RTC, Quality Management System for Call Center, Predictive Dialer and Advanced Request Distribution Server (generalized version of Automated Call Distribution System ACD).

I started with .net 1.1 and gradually moved to .net 2.0, .net 3.0 and .net 4.0 along with WCF and SQL Server 2005 and 2008. I was able to reengineer my own products at Duo by applying proper design pattern to cater extendibility, maintainability and reusability.

I am always glad to share my experience with you and to answer your questions with my own experience. Looking forward to blog with you all we will share each other with what we know.

As Steve Jobs mentioned lets “be hunger be foolish”..