CoderzHeaven

Hello all……

I have written a lost of posts on Listviews. You can see that by just searching Listviews in my site. Today I will show you how to create a slide out animation while we delete a row from a ListView.

So this is the xml that contains the ListView. Let it be in the main.xml

main.xml

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

Create another file inside the layout folder named “simplerow.xml”.

simplerow.xml

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

OK our xml part is over. Now the java part.

This is the main java file that implements this xml.

“SimpleListViewActivity.java”

package com.coderzheaven.pack;

import java.util.ArrayList;

import android.app.Activity;
import android.os.Bundle;
import android.os.Handler;
import android.view.View;
import android.view.animation.Animation;
import android.view.animation.AnimationUtils;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.ListView;
import android.widget.Toast;

public class SimpleListViewActivity extends Activity {
  
  private ListView mainListView ;
  private ArrayAdapter<String> listAdapter ;
   ArrayList<String> all_planets = 
       new ArrayList<String>(){      
           private static final long serialVersionUID = -1773393753338094625L;
           {
               add("Mercury ");
               add("Venus "); 
               add("Earth"); 
               add("Mars"); 
               add("Jupiter"); 
               add("Saturn"); 
               add("Uranus"); 
               add("Neptune"); 
               add("Pluto"); 
           }
   };
   
  @Override
  public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);    
  
    mainListView = (ListView) findViewById( R.id.mainListView );

    listAdapter = new ArrayAdapter<String>(this, R.layout.simplerow, all_planets);

    mainListView.setAdapter( listAdapter );  
    
    mainListView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
        @Override
        public void onItemClick(AdapterView<?> parent, View rowView, int positon,long id) {
            Toast.makeText(rowView.getContext(), ""+positon, Toast.LENGTH_LONG).show();
            removeListItem(rowView,positon);
        }
    });
    
  }
  
  protected void removeListItem(View rowView, final int positon) {

      final Animation animation = AnimationUtils.loadAnimation(SimpleListViewActivity.this,android.R.anim.slide_out_right); 
      rowView.startAnimation(animation);
      Handler handle = new Handler();
      handle.postDelayed(new Runnable() {

		@Override
          public void run() {
        	  all_planets.remove(positon);
              listAdapter.notifyDataSetChanged();
              animation.cancel();
          }
      },1000);

  }

}

OK Done. Now run it and see the result.

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.

Here is a complete example of How to read and write files to SDCARD and application SandBox in Android.

First create a new project and inside the mainActivity paste this code.

package com.coderzheaven.filesexample;

import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;

public class MainActivity extends Activity implements OnClickListener {

	EditText edittext;
	Button b1, b2, b3, b4;
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        
        edittext = (EditText)findViewById(R.id.ed);
        edittext.setLines(10);
        b1 = (Button)findViewById(R.id.button1);
        b2 = (Button)findViewById(R.id.button2);
        b3 = (Button)findViewById(R.id.button3);
        b4 = (Button)findViewById(R.id.button4);
        
        b1.setOnClickListener(this);
        b2.setOnClickListener(this);
        b3.setOnClickListener(this);
        b4.setOnClickListener(this);        
        
    }
	@Override
	public void onClick(View v) {
		int id = v.getId();
		MyFile file = new MyFile(v.getContext());
		
		switch(id){
			case R.id.button1:
				if(!edittext.getText().toString().trim().equals("")){
					file.writeToSD(edittext.getText().toString());
				}else{
					Toast.makeText(v.getContext(), "Please enter some contents for the file", Toast.LENGTH_LONG).show();
				}
				break;
				
			case R.id.button2:
				edittext.setText(file.readFromSD());
				break;
			
			case R.id.button3:
				if(!edittext.getText().toString().trim().equals("")){
					file.writeToSandBox(edittext.getText().toString());
				}else{
					Toast.makeText(v.getContext(), "Please enter some contents for the file", Toast.LENGTH_LONG).show();
				}
				break;
				
			case R.id.button4:
				edittext.setText(file.readFromSandBox());
				break;
		}
		
		
		
	}

}

Now create another class named MyFile.java and copy this code into it.

package com.coderzheaven.filesexample;

import java.io. BufferedReader;
import java.io.BufferedWriter;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;

import android.annotation.SuppressLint;
import android.content.Context;
import android.os.Environment;
import android.util.Log;

public class MyFile {

	String TAG = "MyFile";
	Context context;
	public MyFile(Context context){
		this.context = context;
	}
	
	public Boolean writeToSD(String text){
		Boolean write_successful = false;
		 File root=null;  
	        try {  
	            // check for SDcard   
	            root = Environment.getExternalStorageDirectory();  
	            Log.i(TAG,"path.." +root.getAbsolutePath());  
	  
	            //check sdcard permission  
	            if (root.canWrite()){  
	                File fileDir = new File(root.getAbsolutePath());  
	                fileDir.mkdirs();  
	  
	                File file= new File(fileDir, "samplefile.txt");  
	                FileWriter filewriter = new FileWriter(file);  
	                BufferedWriter out = new BufferedWriter(filewriter);  
	                out.write(text);  
	                out.close();  
	                write_successful = true;
	            }  
	        } catch (IOException e) {  
	            Log.e("ERROR:---", "Could not write file to SDCard" + e.getMessage());  
	            write_successful = false;
	        }  
		return write_successful;
	}
	
	public String readFromSD(){
		File sdcard = Environment.getExternalStorageDirectory();
		File file = new File(sdcard,"samplefile.txt");
		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) {
		}
		return text.toString();
	}

	@SuppressLint("WorldReadableFiles")
	@SuppressWarnings("static-access")
	public Boolean writeToSandBox(String text){
		Boolean write_successful = false;
		try{
			FileOutputStream fOut = context.openFileOutput("samplefile.txt",
					context.MODE_WORLD_READABLE);
			OutputStreamWriter osw = new OutputStreamWriter(fOut); 
			osw.write(text);
			osw.flush();
			osw.close();
		}catch(Exception e){
			write_successful = false;
		}
		return write_successful;
	}
	public String readFromSandBox(){
		String str ="";
		String new_str = "";
		try{
			FileInputStream fIn = context.openFileInput("samplefile.txt");
            InputStreamReader isr = new InputStreamReader(fIn);
            BufferedReader br=new BufferedReader(isr);
           
			while((str=br.readLine())!=null)
            {
				new_str +=str;
				System.out.println(new_str);
            }            
		}catch(Exception e)
		{			
		}
		return new_str;
	}
}

Now the layout for the xml file.

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/LinearLayout1"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:orientation="vertical" >

    <EditText
        android:id="@+id/ed"
        android:layout_width="fill_parent" 
        android:layout_height="fill_parent"
		android:lines="5" android:gravity="top|left" android:inputType="textMultiLine"
		android:scrollHorizontally="false" 
		android:minWidth="10.0dip"
		android:maxWidth="5.0dip"
        android:layout_weight="1"/>


    <Button
        android:id="@+id/button1"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:text="Write File to SDCARD" />
    
    <Button
        android:id="@+id/button2"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:text="Read File from SDCARD" />
    
    <Button
        android:id="@+id/button3"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:text="Write File to Application SandBox" />
    
    <Button
        android:id="@+id/button4"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:text="Read File from Application SandBox" />

</LinearLayout>

Note you should give this permission in the AndroidManifest file.

<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>

OK Done. Now run the project.

To view the files

1. To see the SDCARD
Open File explorer -> expand sdcard (or mnt/sdcard).
2. To see the Application SANDBOX
Open File explorer -> expand data/data/your_package_name/files.

.

Please leave your valuable comments on this post.

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We may have applications in which we may have to make repeated calls to a webservice. At that time services may be useful.

This is such an example in which we will be creating a Service in android to create a repeated call to a webservice in a time delay of some seconds or milliseconds.

OK We will start.

First We will create a new android project named “AcessWebFromService” and in the main java file copy this code.

package com.coderzheaven.pack;

import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;

public class AcessWebFromServiceDemo extends Activity {
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        
        startService(new Intent(AcessWebFromServiceDemo.this, MyService.class));
    }
}

You may be getting some errors after this. Now we will clear all the errors.

Now create another class and name it “MyService.java“. This is our Service file that extends Android Service.

Paste this code into this file .

package com.coderzheaven.pack;

import org.apache.http.client.HttpClient;
import org.apache.http.client.ResponseHandler;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.impl.client.BasicResponseHandler;
import org.apache.http.impl.client.DefaultHttpClient;

import android.app.Service;
import android.content.Intent;
import android.os.IBinder;
import android.util.Log;

public class MyService extends Service{
	
	private static String TAG = MyService.class.getSimpleName();
	private MyThread mythread;
	public boolean isRunning = false;
	
	@Override
	public IBinder onBind(Intent arg0) {
		return null;
	}

	@Override
	public void onCreate() {
		super.onCreate();
		Log.d(TAG, "onCreate");		
		mythread  = new MyThread();
	}

	@Override
	public synchronized void onDestroy() {
		super.onDestroy();
		Log.d(TAG, "onDestroy");
		if(!isRunning){
			mythread.interrupt();
			mythread.stop();
		}		
	}

	@Override
	public synchronized void onStart(Intent intent, int startId) {
		super.onStart(intent, startId); 
		Log.d(TAG, "onStart");
		if(!isRunning){
			mythread.start();
			isRunning = true;
		}
	}
	
	public void readWebPage(){
          HttpClient client = new DefaultHttpClient();
          HttpGet request = new HttpGet("http://google.com");
          // Get the response
          ResponseHandler<String> responseHandler = new BasicResponseHandler();
          String response_str = null;
		  try {
			 response_str = client.execute(request, responseHandler);
			 if(!response_str.equalsIgnoreCase("")){
				 Log.d(TAG, "Got Response");
			 }
		  } catch (Exception e) {
			 e.printStackTrace();
		  }
	}
	
	class MyThread extends Thread{
		static final long DELAY = 3000;
		@Override
		public void run(){			
			while(isRunning){
				Log.d(TAG,"Running");
				try {					
					readWebPage();
					Thread.sleep(DELAY);
				} catch (InterruptedException e) {
					isRunning = false;
					e.printStackTrace();
				}
			}
		}
		
	}

}

We have called this service to start running in the main java file using this code.

startService(new Intent(AcessWebFromServiceDemo.this, MyService.class));

Now the important thing is for this service to run we have to declare it in the AndroidManifest file.

This is how the AndroidManifest file looks.

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
      package="com.coderzheaven.pack"
      android:versionCode="1"
      android:versionName="1.0">
    <application android:icon="@drawable/icon" android:label="@string/app_name">
        <activity android:name=".AcessWebFromServiceDemo"
                  android:label="@string/app_name">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />
                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
        
        <service android:name=".MyService"></service>

    </application>
<uses-permission android:name="android.permission.INTERNET"></uses-permission>
</manifest> 

OK Now you are done. When you run this application you can see the Log coming every three seconds in the LogCat. PLease make sure that you have internet connection in the Emulator or Device.

This is how the Log looks in the Logcat.

Please leave your valuable comments on this post and also share it by hitting a plus(+1) button.

Hello all…

In my previous posts I have shown two methods to create custom progressbar in android.

Check out these tutorials to find out how?

1. How to build a custom progressBar in android- Part 2?
2. Custom progressbar in android with text – part 3

Today in this post I will show you a third method.

Here is the main.xml that contains the progressBar.

<?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" 
    android:gravity="center">
 
 
        <ProgressBar
            android:id="@+id/progressBar1"
             android:indeterminateDrawable="@drawable/progressbackground1"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_alignParentTop="true"
            android:layout_centerHorizontal="true"
            android:layout_margin="20dp" />
 
        <ProgressBar
            android:id="@+id/progressBar2"
             android:indeterminateDrawable="@drawable/progressbackground2"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_centerHorizontal="true"
            android:layout_margin="20dp"  />
         
         <ProgressBar
            android:id="@+id/progressBar3"
             android:indeterminateDrawable="@drawable/progressbackground3"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_centerHorizontal="true"
            android:layout_margin="20dp"  />
            
         <ProgressBar
            android:id="@+id/progressBar4"
             android:indeterminateDrawable="@drawable/progressbackground4"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_centerHorizontal="true"
            android:layout_margin="20dp"  />
 
</LinearLayout>

Now we will create the “android:indeterminateDrawable” xml that is mentioned in the above xml.

Create 4 xml files inside the res/drawable directory whose names and contents are given below.

Here is the first one. “progressbackground1.xml”

<?xml version="1.0" encoding="utf-8"?>
<animated-rotate xmlns:android="http://schemas.android.com/apk/res/android"
android:drawable="@drawable/progressbar1"
android:pivotX="50%"
android:pivotY="50%" />

progressbackground2.xml

<?xml version="1.0" encoding="utf-8"?>
<animated-rotate xmlns:android="http://schemas.android.com/apk/res/android"
android:drawable="@drawable/progressbar2"
android:pivotX="50%"
android:pivotY="50%" />

progressbackground3.xml

<?xml version="1.0" encoding="utf-8"?>
<animated-rotate xmlns:android="http://schemas.android.com/apk/res/android"
android:drawable="@drawable/progressbar3"
android:pivotX="50%"
android:pivotY="50%" />

progressbackground4.xml

<?xml version="1.0" encoding="utf-8"?>
<animated-rotate xmlns:android="http://schemas.android.com/apk/res/android"
android:drawable="@drawable/progressbar4"
android:pivotX="50%"
android:pivotY="50%" />

I have four drawable images inside my res/drawable folder.

Running it will produce the below result.

Please leave your valuable comments on this post.

Download the complete java source code from here.

Hello all……

I have posted two posts on how to customize a progressbar in android.

1. Custom Indeterminate progressBar for android?
2. How to build a custom progressBar in android- Part 2?

Here is another one with update text on top of the progressbar.

Here is how we start.

After creating a fresh project create a new java file and name it “TextProgressBar.java”.

Now copy this code to the above file.
This file extends the progressbar to add additional functionality.

package com.coderzheaven.pack;

import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.Rect;
import android.util.AttributeSet;
import android.widget.ProgressBar;

public class TextProgressBar extends ProgressBar {
	private String text;
	private Paint textPaint;

	public TextProgressBar(Context context) {
		super(context);
		text = "0/100";
		textPaint = new Paint();
		textPaint.setColor(Color.BLACK);
	}

	public TextProgressBar(Context context, AttributeSet attrs) {
		super(context, attrs);
		text = "0/100";
		textPaint = new Paint();
		textPaint.setColor(Color.BLACK);
	}

	public TextProgressBar(Context context, AttributeSet attrs, int defStyle) {
		super(context, attrs, defStyle);
		text = "0/100";
		textPaint = new Paint();
		textPaint.setColor(Color.BLACK);
	}

	@Override
	protected synchronized void onDraw(Canvas canvas) {
		super.onDraw(canvas);
		Rect bounds = new Rect();
		textPaint.getTextBounds(text, 0, text.length(), bounds);
		int x = getWidth() / 2 - bounds.centerX();
		int y = getHeight() / 2 - bounds.centerY();
		canvas.drawText(text, x, y, textPaint);
	}

	public synchronized void setText(String text) {
		this.text = text;
		drawableStateChanged();
	}

	public void setTextColor(int color) {
		textPaint.setColor(color);
		drawableStateChanged();
	}
}

OK the progressbar class is now complete.

Now the xml in which the progressbar contains.

main.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    >
	<TextView  
	    android:layout_width="fill_parent" 
	    android:layout_height="wrap_content" 
	    android:text="Custom ProgressBar Demo from CoderzHeaven"
	    android:textStyle="bold"
	    android:layout_margin="10dp"
    />
    
	<com.coderzheaven.pack.TextProgressBar   
		android:id="@+id/pb"  
		android:layout_width="fill_parent"  
		android:layout_height="wrap_content"  
		android:max="100"  
		android:progress="0"  
		style="?android:attr/progressBarStyleHorizontal"  
		android:maxHeight="20dip"  
		android:minHeight="20dip"  
	/>  
	
</LinearLayout>

Take a look at this line in the xml

This adds the custom progressbar in the xml.

OK Done now we have to just implement in the custom progressbar.

Now the main java file that is calling the progressbar.

package com.coderzheaven.pack;

import android.app.Activity;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;

public class CustomProgressBarDemo extends Activity {
	
	int myProgress = 0;
	TextProgressBar pb;
	
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        
        pb = new TextProgressBar(this);
        pb = (TextProgressBar) findViewById(R.id.pb);  
        new Thread(myThread).start();
    }
    
    private Runnable myThread = new Runnable(){
	  @Override
	  public void run() {	  
		   while (myProgress<100){
			    try{
			    	System.out.println("SSS");
			    	pb.setProgress(myProgress);
			    	pb.setText(myProgress+"/100");
			    	myHandle.sendMessage(myHandle.obtainMessage());
			    	Thread.sleep(500);
			    }
			    catch(Throwable t){
			    }
		   }
	  }

	  Handler myHandle = new Handler(){
		   @Override
		   public void handleMessage(Message msg) {
		    myProgress++;
			pb.setProgress(myProgress);
			pb.setText(myProgress+"/100");
		   }
	  };
	};
}

OK Go on and run the project you will get these results.

Hello all…….

Today I am going to show you how to create a custom progressbar in android.
Previously in another posts I have already shown how to build a custom indeterminate progressbar in android.
And in this post I will show you how to customize the horizontal progressbar.

OK Now we will start.

First create a fresh project and name in “CustomProgressBarDemo_01″ and name the Activity “CustomProgressBarDemo”.

Now copy this code to the the “CustomProgressBarDemo.java” file.

package com.coderzheaven.pack;

import android.app.Activity;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.widget.ProgressBar;

public class CustomProgressBarDemo extends Activity {
	
	int myProgress = 0;
	ProgressBar pb;
	
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        
        pb = (ProgressBar)findViewById(R.id.player_exp_bar);
        pb.setProgressDrawable(getResources().getDrawable(R.drawable.green_progress));  
        new Thread(myThread).start();
    }
    
    private Runnable myThread = new Runnable(){
	  @Override
	  public void run() {	  
		   while (myProgress<100){
			    try{
			    	pb.setProgress(myProgress);
			     myHandle.sendMessage(myHandle.obtainMessage());
			     Thread.sleep(500);
			    }
			    catch(Throwable t){
			    }
		   }
	  }

	  Handler myHandle = new Handler(){
		   @Override
		   public void handleMessage(Message msg) {
		    myProgress++;
		    pb.setProgress(myProgress);
		   }
	  };
	};
}

After pasting it you may get some errors but don’t worry in the coming lines we will remove all that.

Now the layout file “main.xml” which contains the progressbar.

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    >
<TextView  
    android:layout_width="fill_parent" 
    android:layout_height="wrap_content" 
    android:text="Custom ProgressBar Demo from CoderzHeaven"
    android:textStyle="bold"
    android:layout_margin="10dp"
    />
    

	<ProgressBar  
		android:id="@+id/player_exp_bar"  
		android:layout_width="fill_parent"  
		android:layout_height="wrap_content"  
		android:max="100"  
		android:progress="0"  
		style="?android:attr/progressBarStyleHorizontal"  
		android:maxHeight="5dip"  
		android:minHeight="5dip"  
	/>  
	
</LinearLayout>

There may be more errors. Leave it and continue.

Now go to your drawable folder inside the “res” folder and create an xml named “green_progress.xml”.
Copy this code into it.

<?xml version="1.0" encoding="utf-8"?>
<layer-list xmlns:android="http://schemas.android.com/apk/res/android">

<item android:id="@android:id/background">
    <shape>
        <corners android:radius="5dip" />
        <gradient
                android:startColor="#ff9d9e9d"
                android:centerColor="#ff5a5d5a"
                android:centerY="0.75"
                android:endColor="#ff747674"
                android:angle="270"
        />
    </shape>
</item>

<item android:id="@android:id/secondaryProgress">
    <clip>
        <shape>
            <corners android:radius="5dip" />
            <gradient
                    android:startColor="#80ffd300"
                    android:centerColor="#80ffb600"
                    android:centerY="0.75"
                    android:endColor="#a0ffcb00"
                    android:angle="270"
            />
        </shape>
    </clip>
</item>
<item
    android:id="@android:id/progress">
    <clip>
        <shape>
            <corners
                android:radius="5dip" />
            <gradient
                	android:startColor="@color/greenStart"
                    android:centerColor="@color/greenMid"
                    android:centerY="0.75"
                    android:endColor="@color/greenEnd"
                    android:angle="270"
            />
        </shape>
    </clip>
</item>

</layer-list>

OK Now open the strings.xml inside the values folder and copy these code into it.

<?xml version="1.0" encoding="utf-8"?>
<resources>
    <string name="hello">Hello World, CustomProgressBarDemo!</string>
    <string name="app_name">CustomProgressBarDemo</string>
    
    <color name="greenStart">#ff33dd44</color>
	<color name="greenMid">#ff0A8815</color>
	<color name="greenEnd">#ff1da130</color>

</resources>

Ok now I think your errors are cleaned.

It’s time to run the project.

You will see this screen.

I have simulated this progressbar to run to end.

Please share your comments and likes on this post.

Download the complete source code from here.

Hello all …….

I have shown many examples on how to download and upload files in android through this site.

These are other methods for downloadign a file in android.

1. How to Download an image in ANDROID programatically?
2. How to download a file to your android device from a remote server with a custom progressbar showing progress?

I have shown four methods to upload an image to a server.
Check these posts to refer this.

1. Uploading audio, video or image files from Android to server
2. How to Upload Multiple files in one request along with other string parameters in android?
3. ANDROID – Upload an image to a server.
4. How to upload an image from Android device to server? – Method 4

This is yet another example on how to do download a file.

So this is the java code that downloads the file.

package com.coderzheaven.pack;

import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.net.URL;
import java.net.URLConnection;

import android.app.Activity;
import android.app.ProgressDialog;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;

public class DownloadFileDemo extends Activity {
	
	String dwnload_file_path = "http://coderzheaven.com/sample_folder/sample_file.png";
	String dest_file_path = "/sdcard/dwnloaded_file.png";
	Button b1;
	ProgressDialog dialog = null;
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        
        b1 = (Button)findViewById(R.id.Button01);
        b1.setOnClickListener(new OnClickListener() {
			@Override
			public void onClick(View v) {
				
				dialog = ProgressDialog.show(DownloadFileDemo.this, "", "Downloading file...", true);
				 new Thread(new Runnable() {
			            public void run() {
			            	 downloadFile(dwnload_file_path, dest_file_path);
			            }
			          }).start();				
			}
		});
    }
    
    public void downloadFile(String url, String dest_file_path) {
    	  try {
    		  File dest_file = new File(dest_file_path);
    	      URL u = new URL(url);
    	      URLConnection conn = u.openConnection();
    	      int contentLength = conn.getContentLength();

    	      DataInputStream stream = new DataInputStream(u.openStream());

	          byte[] buffer = new byte[contentLength];
	          stream.readFully(buffer);
	          stream.close();

	          DataOutputStream fos = new DataOutputStream(new FileOutputStream(dest_file));
	          fos.write(buffer);
	          fos.flush();
	          fos.close();
	          hideProgressIndicator();
	          
    	  } catch(FileNotFoundException e) {
    		  hideProgressIndicator();
    	      return; 
    	  } catch (IOException e) {
    		  hideProgressIndicator();
    	      return; 
    	  }
    }
    
    void hideProgressIndicator(){
    	runOnUiThread(new Runnable() {
		    public void run() {
		    	dialog.dismiss();
		    }
		});  
    }
}

This is the xml file that contains the button.

main.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    >
<TextView  
    android:layout_width="fill_parent" 
    android:layout_height="wrap_content" 
    android:text="File Download Demo from Coderzheaven \n\nFile to download : http://coderzheaven.com/sample_folder/sample_file.png \n\nSaved Path : sdcard/\n"
    />
<Button 
	android:text="Download File" 
	android:id="@+id/Button01" 
	android:layout_width="wrap_content" 
	android:layout_height="wrap_content">
</Button>
</LinearLayout>

Note : Please add these two permissions in the AndroidManifest.xml

  <uses-permission android:name="android.permission.INTERNET"/>    
   <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>

Please leave your comments and also share this post if you like it.

Actually this is really simple.

I have already posted an example for how to download a file in this post.

How to Download an image in ANDROID programatically?

This is another one little different with a progressbar included.

Previously I have shown three other methods to upload files to a server.
Check these posts to refer this.

1. Uploading audio, video or image files from Android to server
2. How to Upload Multiple files in one request along with other string parameters in android?
3. ANDROID – Upload an image to a server.

OK We will start now.
This is the file we are going to download.

http://coderzheaven.com/sample_folder/sample_file.png

First we will create a simple layout with a button that will download a file on it’s onClick event.

This is the contents of main.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    >
<TextView  
	android:id="@+id/tv1"
    android:layout_width="fill_parent" 
    android:layout_height="wrap_content" 
    android:text="Downloading File with ProgressBar Demo From Coderzheaven"
    />
<Button 
	android:id="@+id/b1"
    android:layout_width="wrap_content" 
    android:layout_height="wrap_content" 
    android:text="Download File"
    android:onClick="downloadFile"
    />
</LinearLayout>

Now we will write the java code to download the file.
Copy this code to your main java file. My file is named “DownloadFileDemo1.java”.

package com.coderzheaven.pack;

import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;

import android.app.Activity;
import android.app.Dialog;
import android.os.Bundle;
import android.os.Environment;
import android.view.View;
import android.view.Window;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.ProgressBar;
import android.widget.TextView;
import android.widget.Toast;

public class DownloadFileDemo1 extends Activity {
	
    ProgressBar pb;
    Dialog dialog;
    int downloadedSize = 0;
    int totalSize = 0;
    TextView cur_val;
    String dwnload_file_path = "http://coderzheaven.com/sample_folder/sample_file.png";
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
      
        Button b = (Button) findViewById(R.id.b1);
        b.setOnClickListener(new OnClickListener() {
			@Override
			public void onClick(View v) {
				 showProgress(dwnload_file_path);
			        
			        new Thread(new Runnable() {
			            public void run() {
			            	 downloadFile();
			            }
			          }).start();
			}
		});
    }
  	    
    void downloadFile(){
    	
    	try {
    		URL url = new URL(dwnload_file_path);
    		HttpURLConnection urlConnection = (HttpURLConnection) url.openConnection();

    		urlConnection.setRequestMethod("GET");
    		urlConnection.setDoOutput(true);

    		//connect
    		urlConnection.connect();

    		//set the path where we want to save the file    		
    		File SDCardRoot = Environment.getExternalStorageDirectory(); 
    		//create a new file, to save the downloaded file 
    		File file = new File(SDCardRoot,"downloaded_file.png");
 
    		FileOutputStream fileOutput = new FileOutputStream(file);

    		//Stream used for reading the data from the internet
    		InputStream inputStream = urlConnection.getInputStream();

    		//this is the total size of the file which we are downloading
    		totalSize = urlConnection.getContentLength();

    		runOnUiThread(new Runnable() {
			    public void run() {
			    	pb.setMax(totalSize);
			    }			    
			});
    		
    		//create a buffer...
    		byte[] buffer = new byte[1024];
    		int bufferLength = 0;

    		while ( (bufferLength = inputStream.read(buffer)) > 0 ) {
    			fileOutput.write(buffer, 0, bufferLength);
    			downloadedSize += bufferLength;
    			// update the progressbar //
    			runOnUiThread(new Runnable() {
    			    public void run() {
    			    	pb.setProgress(downloadedSize);
    			    	float per = ((float)downloadedSize/totalSize) * 100;
    			    	cur_val.setText("Downloaded " + downloadedSize + "KB / " + totalSize + "KB (" + (int)per + "%)" );
    			    }
    			});
    		}
    		//close the output stream when complete //
    		fileOutput.close();
    		runOnUiThread(new Runnable() {
			    public void run() {
			    	// pb.dismiss(); // if you want close it..
			    }
			});    		
    	
    	} catch (final MalformedURLException e) {
    		showError("Error : MalformedURLException " + e);  		
    		e.printStackTrace();
    	} catch (final IOException e) {
    		showError("Error : IOException " + e);  		
    		e.printStackTrace();
    	}
    	catch (final Exception e) {
    		showError("Error : Please check your internet connection " + e);
    	}    	
    }
    
    void showError(final String err){
    	runOnUiThread(new Runnable() {
		    public void run() {
		    	Toast.makeText(DownloadFileDemo1.this, err, Toast.LENGTH_LONG).show();
		    }
		});
    }
    
    void showProgress(String file_path){
    	dialog = new Dialog(DownloadFileDemo1.this);
    	dialog.requestWindowFeature(Window.FEATURE_NO_TITLE);
    	dialog.setContentView(R.layout.myprogressdialog);
    	dialog.setTitle("Download Progress");

    	TextView text = (TextView) dialog.findViewById(R.id.tv1);
    	text.setText("Downloading file from ... " + file_path);
    	cur_val = (TextView) dialog.findViewById(R.id.cur_pg_tv);
    	cur_val.setText("Starting download...");
    	dialog.show();
    	
    	pb = (ProgressBar)dialog.findViewById(R.id.progress_bar);
    	pb.setProgress(0);
    	pb.setProgressDrawable(getResources().getDrawable(R.drawable.green_progress));  
    }
}

OK now we have to make a layout for the progressdialog since it is a custom one.

create a new xml file inside res/layout folder and name it myprogressdialog.xml and copy this code into it.

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
              android:id="@+id/layout_root"
              android:orientation="vertical"
              android:layout_width="fill_parent"
              android:layout_height="fill_parent"
              android:padding="10dp"
              >
    
    <TextView 
    	android:id="@+id/tv1"
      	android:layout_width="wrap_content"
      	android:layout_height="wrap_content"
      	android:textColor="#FFF"
      	android:text="hello"
      	android:textStyle="bold"  
    />
       
    <TextView 
    	android:id="@+id/cur_pg_tv"
      	android:layout_width="wrap_content"
      	android:layout_height="wrap_content"
      	android:textColor="#0F0"
      	android:text="hello"
      	android:layout_marginTop="5dp"
      	android:textStyle="bold|italic"    />       
    <ProgressBar   
		android:id="@+id/progress_bar"  
		android:layout_width="fill_parent"  
		android:layout_height="wrap_content"  
		android:progress="0"  
		android:layout_marginTop="5dp"
		android:layout_marginBottom="10dp"
		style="?android:attr/progressBarStyleHorizontal"  
		android:maxHeight="10dip"  
		android:minHeight="10dip"  
	/>  
	
</LinearLayout>

Now create a new file inside res/drawable folder and name it “green_progress.xml” and copy this code into it.
This xml is used for giving a green color to the progressbar.

<?xml version="1.0" encoding="utf-8"?>
<layer-list xmlns:android="http://schemas.android.com/apk/res/android">

<item android:id="@android:id/background">
    <shape>
        <corners android:radius="5dip" />
        <gradient
                android:startColor="#ff9d9e9d"
                android:centerColor="#ff5a5d5a"
                android:centerY="0.75"
                android:endColor="#ff747674"
                android:angle="270"
        />
    </shape>
</item>
<item
    android:id="@android:id/progress">
    <clip>
        <shape>
            <corners
                android:radius="5dip" />
            <gradient
                	android:startColor="@color/greenStart"
                    android:centerColor="@color/greenMid"
                    android:centerY="0.75"
                    android:endColor="@color/greenEnd"
                    android:angle="270"
            />
        </shape>
    </clip>
</item>
</layer-list>

OK now we have customized the progressbar.

This line sets the progressbar to green color.

pb.setProgressDrawable(getResources().getDrawable(R.drawable.green_progress));

The showProgress() method inside the java code will invoke the custom progressbar.

Now the main thing..
Dont forget to add the permissions to the manifest file.

These two are the permissions we need .

This is the AndroidManifest file for this example.

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
      package="com.coderzheaven.pack"
      android:versionCode="1"
      android:versionName="1.0">
      
    <uses-permission android:name="android.permission.INTERNET" />
    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
    
    <application android:icon="@drawable/icon" android:label="@string/app_name">
        <activity android:name=".DownloadFileDemo1"
                  android:label="@string/app_name">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />
                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    </application>
</manifest> 

The file will be downloaded to the sdcard root. Please go to the DDMS perpective and open the File Explorer and expand the SDCARD to see the downloaded file.

Check the screen shot..

.

I ran into problem when I had multiple C files in my project. Single C file was OK for me.
I was getting undefined reference error while doing this.
Then I found out the solution after a lot of search in google.

You can check this post before going through this post.
This is about setting up NDK in MAC.
Starting with NDK for Android – A Simple example. OR How to run a C code in android?

I have to make the change in the Android.mk file to include other files to compile.

This is the content of my Android.mk file

LOCAL_PATH := $(call my-dir)
 
include $(CLEAR_VARS)
 
LOCAL_LDLIBS := -llog
 
LOCAL_MODULE    := ndksetup
LOCAL_SRC_FILES := native.c test.c test_2.c
 
include $(BUILD_SHARED_LIBRARY)

Here is my native.c code in which I am including those two files test.c and test2.c

#include <jni.h>
#include <string.h>
#include <android/log.h>

// my test file 
#include "test.h"
#include "test_2.h"

#define DEBUG_TAG "NDKSetupActivity"
 
void Java_com_ndksetup_NDKSetupActivity_printLog(JNIEnv * env, jobject this, jstring logString)
{
    jboolean isCopy;
    const char * szLogString = (*env)->GetStringUTFChars(env, logString, &isCopy);
 
    __android_log_print(ANDROID_LOG_DEBUG, "TAGGGGG", "NDK: %s", szLogString);
 
    (*env)->ReleaseStringUTFChars(env, logString, szLogString);
}
int Java_com_ndksetup_NDKSetupActivity_fibonacci(int value)
{
	int p = 8;
	printMe();
	printMe2();
	return p;
}

Hi all…..

This example reads the file line by line using readLine() function till the end of the file. Here your need two classes named “InputStreamReader” and “BufferedReader”. For writing into the file you need “OutputStreamReader” class. The result is displayed in a Toast. Make sure you notice it.

The following is the code for reading the text file………

String     res  =    null;
try {

	   InputStream       in = openFileInput("myfile.txt");

	   if (in != null) {
	    // prepare the file for reading
	     InputStreamReader input = new InputStreamReader(in);
	     BufferedReader buffreader = new BufferedReader(input);

	      res = "";
	      while (( line = buffreader.readLine()) != null) {
	      	res += line;
	      }
	      in.close();
	      Toast.makeText(getApplicationContext(),"File Contents ==> " + res,Toast.LENGTH_SHORT).show();
          }else{
	    }

} catch(Exception e){
       Toast.makeText(getApplicationContext(),     e.toString() +   e.getMessage(),Toast.LENGTH_SHORT).show();
}

Want More then

How to read and write files to SDCARD and application SandBox in Android – A complete example?

Please leave your comments on this post.

Hello all..

This simple example will show you how to change the hint text color in android

Here is the java code to simply do this.

youredittext.setHint(Html.fromHtml("<font color='#FF0000'>Hello</font> "));

here is a sample project to view the difference.

This is the contents of the main java file.

package com.coderzheaven.pack;

import android.app.Activity;
import android.os.Bundle;
import android.text.Html;
import android.widget.EditText;

public class HintColorDemoActivity extends Activity {
@Override
public void onCreate(Bundle savedInstanceState) {
          super.onCreate(savedInstanceState);
          setContentView(R.layout.main);

          EditText ed = (EditText)findViewById(R.id.editText1);
          ed.setHint("Hello ");

          EditText ed2 = (EditText)findViewById(R.id.editText2);
          ed2.setHint(Html.fromHtml("<font color='#FF0000'>Hello</font> "));
     }
}

The main.xml file

<?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" >

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

     <EditText
          android:id="@+id/editText1"
          android:layout_width="match_parent"
          android:layout_height="wrap_content"
          android:ems="10" >

          <requestFocus />
     </EditText>

     <EditText
          android:id="@+id/editText2"
          android:layout_width="match_parent"
          android:layout_height="wrap_content"
          android:ems="10" >
     </EditText>
</LinearLayout>

Here I am setting a read color to the second edittext hint.
See the screenshot.

Please leave your comments if you found this useful.

Hey all…

This is a very simple thing to do in android.
Just copy this code to see this.

here is the main java file

package pack.coderzheaven;

import android.app.Activity;
import android.graphics.Bitmap;
import android.graphics.drawable.BitmapDrawable;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.LinearLayout;

public class ScreenShotDemo extends Activity {
	LinearLayout L1;
	ImageView image;
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        L1 = (LinearLayout) findViewById(R.id.LinearLayout01);
        Button but = (Button) findViewById(R.id.Button01);
        but.setOnClickListener(new View.OnClickListener() {
	        @Override
	        public void onClick(View v) {
		        View v1 = L1.getRootView();
		        v1.setDrawingCacheEnabled(true);
		        Bitmap bm = v1.getDrawingCache();
		        BitmapDrawable bitmapDrawable = new BitmapDrawable(bm);
		        image = (ImageView) findViewById(R.id.ImageView01);
		        image.setBackgroundDrawable(bitmapDrawable);
		    }
	   });
  }
}

And this is the layout file main.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:id="@+id/LinearLayout01"
    >
<Button
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:text="Take Screenshot"
    android:id="@+id/Button01"
    />

  <ImageView
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:text="Take Screenshot"
    android:id="@+id/ImageView01"
    />
</LinearLayout>

ScreenShot in android

Hello Friends….

Today I am going to talk about how to use ndk in android to run c code.

Note : These steps are for Mac and Linux Users not for Windows users.

Follow these step exactly to set up and run ndk in android.

1. I think that you are having your eclipse and android uptodate.
2. Go to this place “http://developer.android.com/sdk/ndk/index.html” and download the ndk for your operating system.

3. After downloading the zip, extract it and save it in your own location.

4. Now we are going to create the android Project.
I am naming it “NDKDemo” and the activity is named “NDKDemoActivity”.

Now create a folder named “jni” in the project.

5. Click on jni folder-> then go to “Run Menu” > external tools > external tools configuration.

6. Click on Program and click on the new icon (first icon) on the top. On the right side Give the NDK a name.

In the Next Location textbox Click on “Browse File System” and located the ndk-build that you just downloaded from “developer.android.com”

7. Now in the Workspace location > Click on Browse Workspace and select your “jni” folder in the “NDKDemo” project directory.

This dialog comes when you click the Browse Workspace button and select the jni folder in your project and click OK.

8. Now create a file named “Android.mk” file inside the “jni” folder.

copy this code to “Android.mk” file.

LOCAL_PATH := $(call my-dir)

include $(CLEAR_VARS)

LOCAL_LDLIBS := -llog

LOCAL_MODULE    := ndkdemo
LOCAL_SRC_FILES := native.c

include $(BUILD_SHARED_LIBRARY)

9. Now create another file named “native.c” inside the jni folder and copy this code into it.
This is our c code.
This don’t look purely like a c code because it has some java elements inside it.

#include <jni.h>
#include <string.h>
#include <android/log.h>

#define DEBUG_TAG "NDKDemoActivity"

void Java_com_coderzheaven_pack__NDKDemoActivity_printLog(JNIEnv * env, jobject this, jstring logString)
{
    jboolean isCopy;
    const char * szLogString = (*env)->GetStringUTFChars(env, logString, &isCopy);

    __android_log_print(ANDROID_LOG_DEBUG, DEBUG_TAG, "NDK: %s", szLogString);

    (*env)->ReleaseStringUTFChars(env, logString, szLogString);
}

Note :
Please take a look the function name

OK Everything needed for NDK is done.
10. Now what we have to do is to compile the c code. For that go to “Run” > external tools > select NDK you created and run.

Now the c code has been compiled.

11. Now in the java Activity copy this code

package com.coderzheaven.pack;

import android.app.Activity;
import android.os.Bundle;

public class NDKDemoActivity extends Activity {
	  static {
	        System.loadLibrary("ndkdemo");
	    }

	    @Override
	    public void onCreate(Bundle savedInstanceState) {
	        super.onCreate(savedInstanceState);
	        setContentView(R.layout.main);
	        printLog("Hello Coderzheaven");
	    }

	    private native void printLog(String logThis);
}

12. Now run this project and check the Logcat for the message after calling the C function from android.

You can any number of c functions inside the native.c code and run it.
Make sure to put a declaration on top of the activity before calling.

Please leave your comments if this post was useful.

Hello everyone

Today I will explain how will you call a function that is defined inside the java android code from a webview.
For this we need to add a webviewclient in android for the WebView we are adding in the xml.

Then we have to register the webviewclient with the WebView we are creating using this method.

 myWebView.setWebViewClient(new MyWebViewClient());

Now we will start….

Create a new project and name it WebViewDemo.

Now in the main.xml copy this code.
This file contains the webview only.

<?xml version="1.0" encoding="utf-8"?>
<WebView  xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/webview"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
/>

Now create a file named test.html inside the assets folder and copy this code into it. This is the html file that we are loading into the webview.

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML Basic 1.1//EN"
    "http://www.w3.org/TR/xhtml-basic/xhtml-basic11.dtd">
<html>
<body>
<a href="http://www.coderzheaven.com">CoderzHeaven</a>
<input type="button" value="Click Me" onClick="showAndroidToast('Hello CoderzHeaven!')" />
<script type="text/javascript">
    function showAndroidToast(toast) {
    	Android.showToast(toast);
    }
</script>
</body>
</html>

Now in the java code refer the webview and load the html file

WebView myWebView;
 myWebView = (WebView) findViewById(R.id.webview);
 myWebView.loadUrl("file:///android_asset/test.html");

Now enable the javascript by calling this function

 WebSettings webSettings = myWebView.getSettings();
 webSettings.setJavaScriptEnabled(true);

Now we have to add the javascript interface for listening to the javascript functions that we define in the webview html file.

  myWebView.addJavascriptInterface(new JavaScriptInterface(this), "Android");

// outside oncreate
 public class JavaScriptInterface {
        Context mContext;

        /** Instantiate the interface and set the context */
        JavaScriptInterface(Context c) {
            mContext = c;
        }

        /** Show a toast from the web page */
        public void showToast(String toast) {
            Toast.makeText(mContext, toast, Toast.LENGTH_SHORT).show();
            startActivity(new Intent(WebViewDemo.this, WebViewDemo.class));
        }
    }

Now create a webview client for listening to the browser activities and doing specific function.

 myWebView.setWebViewClient(new MyWebViewClient());

 private class MyWebViewClient extends WebViewClient {
        @Override
        public boolean shouldOverrideUrlLoading(WebView view, String url) {
            if (Uri.parse(url).getHost().equals("www.coderzheaven.com")) {
               	Toast.makeText(getApplicationContext(), "www.coderzheaven.com", Toast.LENGTH_SHORT).show();
                return false;
            }
            // Otherwise, the link is not for a page on my site, so launch another Activity that handles URLs
            Intent intent = new Intent(Intent.ACTION_VIEW, Uri.parse(url));
            startActivity(intent);
            return true;
        }
    }

Now we listen to the backbutton.

 @Override
    public boolean onKeyDown(int keyCode, KeyEvent event) {
        // Check if the key event was the BACK key and if there's history
        if ((keyCode == KeyEvent.KEYCODE_BACK) && myWebView.canGoBack()) {
            myWebView.goBack();
            return true;
        }
        return super.onKeyDown(keyCode, event);
    }

Now the project is over . Now run and see the result.
Here is the full java code for this example

package com.coderzheaven.pack;

import android.app.Activity;
import android.content.Context;
import android.content.Intent;
import android.net.Uri;
import android.os.Bundle;
import android.view.KeyEvent;
import android.webkit.WebSettings;
import android.webkit.WebView;
import android.webkit.WebViewClient;
import android.widget.Toast;

public class WebViewDemo extends Activity {

	WebView myWebView;
    @Override
    public void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        myWebView = (WebView) findViewById(R.id.webview);
        myWebView.loadUrl("file:///android_asset/test.html");
        WebSettings webSettings = myWebView.getSettings();
        webSettings.setJavaScriptEnabled(true);

        myWebView.addJavascriptInterface(new JavaScriptInterface(this), "Android");

       // myWebView.setWebViewClient(new WebViewClient());
        myWebView.setWebViewClient(new MyWebViewClient());
    }

    public class JavaScriptInterface {
        Context mContext;

        /** Instantiate the interface and set the context */
        JavaScriptInterface(Context c) {
            mContext = c;
        }

        /** Show a toast from the web page */
        public void showToast(String toast) {
            Toast.makeText(mContext, toast, Toast.LENGTH_SHORT).show();
            startActivity(new Intent(WebViewDemo.this, WebViewDemo.class));
        }
    }

    private class MyWebViewClient extends WebViewClient {
        @Override
        public boolean shouldOverrideUrlLoading(WebView view, String url) {
            if (Uri.parse(url).getHost().equals("www.google.com")) {
                // This is my web site, so do not override; let my WebView load the page
            	Toast.makeText(getApplicationContext(), "www.google.com", Toast.LENGTH_SHORT).show();
                return false;
            }
            // Otherwise, the link is not for a page on my site, so launch another Activity that handles URLs
            Intent intent = new Intent(Intent.ACTION_VIEW, Uri.parse(url));
            startActivity(intent);
            return true;
        }
    }

    @Override
    public boolean onKeyDown(int keyCode, KeyEvent event) {
        // Check if the key event was the BACK key and if there's history
        if ((keyCode == KeyEvent.KEYCODE_BACK) && myWebView.canGoBack()) {
            myWebView.goBack();
            return true;
        }
        // If it wasn't the BACK key or there's no web page history, bubble up to the default
        // system behavior (probably exit the activity)
        return super.onKeyDown(keyCode, event);
    }
}

Calling an android function from javascript

please leave your valuable comments if this post was useful.

Hello everyone,

Today’s example shows how to create a custom layout for your camera preview, that is if you want a custom layout while your camera is opening.
This example helps you to achieve this.

First create a fresh project and name it CameraCustomLayout and copy this code to CameraCustomLayout.java file.

package com.coderzheaven.pack;

import java.io.IOException;
import android.app.Activity;
import android.content.pm.ActivityInfo;
import android.graphics.PixelFormat;
import android.hardware.Camera;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.SurfaceHolder;
import android.view.SurfaceView;
import android.view.View;
import android.view.ViewGroup.LayoutParams;

public class CustomCameraActivity extends Activity implements SurfaceHolder.Callback {

	Camera camera;
	SurfaceView surfaceView;
	SurfaceHolder surfaceHolder;
	boolean previewing = false;
	LayoutInflater controlInflater = null;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_LANDSCAPE);

        getWindow().setFormat(PixelFormat.UNKNOWN);
        surfaceView = (SurfaceView)findViewById(R.id.camerapreview);
        surfaceHolder = surfaceView.getHolder();
        surfaceHolder.addCallback(this);
        surfaceHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);

        controlInflater = LayoutInflater.from(getBaseContext());
        View viewControl = controlInflater.inflate(R.layout.custom, null);
        LayoutParams layoutParamsControl = new LayoutParams(LayoutParams.FILL_PARENT,
        								   					LayoutParams.FILL_PARENT);
        this.addContentView(viewControl, layoutParamsControl);
    }

	@Override
	public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {
		if(previewing){
			camera.stopPreview();
			previewing = false;
		}

		if (camera != null){
			try {
				camera.setPreviewDisplay(surfaceHolder);
				camera.startPreview();
				previewing = true;
			} catch (IOException e) {
				e.printStackTrace();
			}
		}
	}

	@Override
	public void surfaceCreated(SurfaceHolder holder) {
		camera = Camera.open();
	}

	@Override
	public void surfaceDestroyed(SurfaceHolder holder) {
		camera.stopPreview();
		camera.release();
		camera = null;
		previewing = false;
	}
}

After that create an xml file named custom.xml inside the res/layout folder and copy this code into it.
This is the layout which comes when you open the camera in your device.

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

	<Button
		android:text="Click Me"
		android:id="@+id/Button01"
		android:layout_width="wrap_content"
		android:layout_height="wrap_content">
	</Button>
	<Button
		android:text="Click Me too"
		android:id="@+id/Button02"
		android:layout_width="wrap_content"
		android:layout_height="wrap_content">
	</Button>
</LinearLayout>

Now in the main.xml file copy this code.
This file contains the SurfaceView which holds the cameraPreview.

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

Now you are done.
Note : Please run it on a real device, because camera will not work on the emulator.

You can download the source code from here.
PLease dont forget to comment on this post if you like it.

In android the default transition between activities is to slide from left to right.
But with custom animations we can change that.

First create a folder inside the res/drawable folder called “anim”.
Then create a file named “fade.xml” and copy this code into it.

<?xml version="1.0" encoding="utf-8"?>
<alpha xmlns:android="http://schemas.android.com/apk/res/android"
       android:interpolator="@android:anim/accelerate_interpolator"
       android:fromAlpha="0.0" android:toAlpha="1.0"
       android:duration="@android:integer/config_longAnimTime" />

create another file named “hold.xml” in the same place
hold.xml.

<?xml version="1.0" encoding="utf-8"?>
<translate xmlns:android="http://schemas.android.com/apk/res/android"
       android:interpolator="@android:anim/accelerate_interpolator"
       android:fromXDelta="0" android:toXDelta="0"
       android:duration="@android:integer/config_longAnimTime" />

activity_animation.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:orientation="vertical" android:padding="4dip"
    android:gravity="center_horizontal"
    android:layout_width="fill_parent" android:layout_height="fill_parent">

    <TextView
        android:layout_width="fill_parent" android:layout_height="wrap_content"
        android:layout_weight="0"
        android:paddingBottom="4dip"
        android:text="Sample Animation"/>

    <Button android:id="@+id/fade_animation"
        android:layout_width="wrap_content" android:layout_height="wrap_content"
        android:text="fade In">
        <requestFocus />
    </Button>
</LinearLayout>

Now the main java file.

package pack.coderzheaven;

import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;

public class ActivityAnimation extends Activity {
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_animation);

        Button button = (Button)findViewById(R.id.fade_animation);
        button.setOnClickListener(mFadeListener);
    }

    private OnClickListener mFadeListener = new OnClickListener() {
        public void onClick(View v) {
            startActivity(new Intent(ActivityAnimation.this, SecondClass.class));
            overridePendingTransition(R.anim.fade, R.anim.hold);
        }
    };
}

package pack.coderzheaven;

import android.app.Activity;
import android.os.Bundle;

public class SecondClass extends Activity {
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
}
}

main.xml

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

Hello all…..

In today’s tutorial I will show you how to create a custom listview in android.
For that we need 3java files.
One holding the ListView itself another a Model object that holds the data for the listview and the third one for the Adapter which extends the ArrayAdapter class for holding the model.

First the Model.java file

package pack.coderzheaven;

public class Model {

	private String name;
	private String place;
	private boolean selected;

	public Model(String name, String place) {
		this.name = name;
		this.place = place;
		selected = false;
	}

	public String getName() {
		return name;
	}

	public String getPlace() {
		return place;
	}

	public void setName(String name) {
		this.name = name;
	}

	public void setPlace(String place) {
		this.place = place;
	}

	public boolean isSelected() {
		return selected;
	}

	public void setSelected(boolean selected) {
		this.selected = selected;
	}

}

Now the second file MyCustomArrayAdapter.java that extends the Arrayadapter class.

package pack.coderzheaven;

import java.util.List;

import android.app.Activity;
import android.graphics.Color;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;
import android.widget.CheckBox;
import android.widget.CompoundButton;
import android.widget.TextView;

public class MyCustomArrayAdapter extends ArrayAdapter<Model> {

	private final List<Model> list;
	private final Activity context;

	public MyCustomArrayAdapter(Activity context, List<Model> list) {
		super(context, R.layout.list_layout, list);
		this.context = context;
		this.list = list;
	}

	static class ViewHolder {
		protected TextView text, sub;
		protected CheckBox checkbox;
	}

	@Override
	public View getView(int position, View convertView, ViewGroup parent) {
		View view = null;
		if (convertView == null) {
			LayoutInflater inflator = context.getLayoutInflater();
			view = inflator.inflate(R.layout.list_layout, null);
			final ViewHolder viewHolder = new ViewHolder();
			viewHolder.text = (TextView) view.findViewById(R.id.label);
			viewHolder.text.setTextColor(Color.BLACK);
			viewHolder.sub = (TextView) view.findViewById(R.id.sub);
			viewHolder.sub.setTextColor(Color.GRAY);
			viewHolder.checkbox = (CheckBox) view.findViewById(R.id.check);
			viewHolder.checkbox
					.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
						@Override
						public void onCheckedChanged(CompoundButton buttonView,
								boolean isChecked) {
							Model element = (Model) viewHolder.checkbox.getTag();
							element.setSelected(buttonView.isChecked());
							System.out.println("Checked : " + element.getName());
						}
					});
			view.setTag(viewHolder);
			viewHolder.checkbox.setTag(list.get(position));
		} else {
			view = convertView;
			((ViewHolder) view.getTag()).checkbox.setTag(list.get(position));
		}
		ViewHolder holder = (ViewHolder) view.getTag();
		holder.text.setText(list.get(position).getName());
		holder.sub.setText(list.get(position).getPlace());
		holder.checkbox.setChecked(list.get(position).isSelected());
		return view;
	}
}

Now the main Java file which is named ModelListViewActivity.java

package pack.coderzheaven;

import java.util.ArrayList;
import java.util.List;

import android.app.ListActivity;
import android.os.Bundle;
import android.widget.ArrayAdapter;

public class ModelListViewActivity extends ListActivity {

	public void onCreate(Bundle icicle) {
		super.onCreate(icicle);
		setContentView(R.layout.main);

		ArrayAdapter<Model> adapter = new MyCustomArrayAdapter(this,	getModel());
		setListAdapter(adapter);
	}

	private List<Model> getModel() {
		List<Model> list = new ArrayList<Model>();
		list.add(get("Android","Google"));
		list.add(get("Windows 7","Microsoft"));
		list.add(get("iPhone","Apple"));
		list.add(get("Ubuntu","Linux"));
		list.add(get("Bada","Samsung"));
		list.add(get("Android","Google"));
		list.add(get("Symbian","Nokia"));
		list.add(get("Windows 7","Microsoft"));
		list.get(1).setSelected(true);	// select one item by default
		return list;
	}

	private Model get(String s,String place) {
		return new Model(s,place);
	}
}

Now the layout for each row in the ListView. – list_layout.xml

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
	android:layout_width="fill_parent" android:layout_height="wrap_content">
	<TextView android:text="@+id/label" android:layout_width="wrap_content"
		android:layout_height="wrap_content" android:id="@+id/label"
		android:layout_marginLeft="15dp"
		android:layout_marginTop="5dp"
		android:textStyle="bold"
		android:textSize="20px"></TextView>
	<TextView android:text="@+id/sub"
		android:layout_below="@+id/label"
			android:layout_width="wrap_content"
		android:layout_height="wrap_content" android:id="@+id/sub"
		android:layout_marginLeft="15dp"
		android:textSize="15px"></TextView>
	<CheckBox android:id="@+id/check" android:layout_width="wrap_content"
		android:layout_height="wrap_content" android:layout_marginLeft="4px"
		android:layout_marginRight="10px" android:layout_alignParentRight="true"
		></CheckBox>
</RelativeLayout>

Now the main.xml file that holds the ListView.

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    >
	 <ListView
			android:id="@id/android:list"
			android:layout_width="fill_parent"
			android:layout_height="wrap_content"
			android:background="@drawable/customshape"
			android:dividerHeight="1px"
			android:cacheColorHint="#0000"
			android:clipToPadding="true"
			android:layout_margin="5dp"
			android:soundEffectsEnabled="true"
			android:scrollbars="none">
	</ListView>
</LinearLayout>

customshape.xml (in the drawable folder)

<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
    <item>
        <shape>
             <gradient
                android:endColor ="#000000"
                android:startColor="#FFFF0000"
                android:angle="270" />
            <stroke
                android:width="0dp"
                android:color="#C2C2C2" />
            <corners
                android:radius="5dp" />
        </shape>
    </item>   
</selector>

Now the AndroidManifest.xml file.

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
      package="pack.coderzheaven"
      android:versionCode="1"
      android:versionName="1.0">
    <uses-sdk android:minSdkVersion="6" />

    <application android:icon="@drawable/icon" android:label="@string/app_name">
        <activity android:name=".ModelListViewActivity"
                  android:label="@string/app_name">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />
                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>

    </application>
</manifest>

Custom ListView

Hello everyone today i will show you how to create a splash screen in android.
This is one of the simplest ways to create a splash screen however there are another ways to create the splash screen.
Lets look at the code.

We need two layouts one for the splash screen and another for the first screen that comes after splash screen.

The splash screen layout will look like this.
splashscreen.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">
    <ImageView android:src="@drawable/android"
    android:layout_width="fill_parent"
     android:id="@+id/imageView1"
     android:layout_height="fill_parent"></ImageView>
</LinearLayout>

Now the main.xml file.

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    >
<TextView
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:text="Splash screen Demo from CoderzHeaven"
    />
</LinearLayout>

Now the main java file.

package pack.coderzheaven;

import android.app.Activity;
import android.os.Bundle;
import android.os.CountDownTimer;

public class SplashScreenDemo extends Activity {
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.splashscreen);
        creatingSplashScreen();
    }

	private void createFirstScreen()
	{
	    	   setContentView(R.layout.main);
	}

	private void creatingSplashScreen()
	{
		 new CountDownTimer(5000, 1000) {
                   public void onTick(long millisUntilFinished)
		     {
		     }

		     public void onFinish() {
		    	 createFirstScreen();
		     }
		  }.start();
	}
}

Make sure you have an image named “android.png” or “android.jpg” in your res/drawable folder.

Hello everyone..
In one of my tutorials I have shown you how to upload an image in android..
In todays tutorial I will show you how to download an image into your phone programatically.
I am just picking up an image url from google to show the download.

Previously I have shown three other methods to upload files to a server.
Check these posts to refer this.

1. Uploading audio, video or image files from Android to server
2. How to Upload Multiple files in one request along with other string parameters in android?
3. ANDROID – Upload an image to a server.

This is the main program that downloads the file.

package pack.coderzheaven;

import java.io.BufferedInputStream;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.URL;
import java.net.URLConnection;
import org.apache.http.util.ByteArrayBuffer;
import android.app.Activity;
import android.os.Bundle;
import android.widget.TextView;

public class DownloadImage extends Activity {

	private final String PATH = "/data/data/pack.coderzheaven/";
	TextView tv;
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        tv = (TextView)findViewById(R.id.tv);
        DownloadFromUrl(PATH+"dwn_img.jpg");
    }
    public void DownloadFromUrl(String fileName) {
            try {
                    URL url = new URL("http://t3.gstatic.com/images?q=tbn:ANd9GcQs0EPegqi56Alq4vCgC_lVDbZvJtk51RhER7AyDEVA3nUkzjMVK-yDHY3V-w"); //you can write here any link
                    File file = new File(fileName);

                    long startTime = System.currentTimeMillis();
                    tv.setText("Starting download......from " + url);
                    URLConnection ucon = url.openConnection();
                    InputStream is = ucon.getInputStream();
                    BufferedInputStream bis = new BufferedInputStream(is);
                    /*
                     * Read bytes to the Buffer until there is nothing more to read(-1).
                     */
                    ByteArrayBuffer baf = new ByteArrayBuffer(50);
                    int current = 0;
                    while ((current = bis.read()) != -1) {
                            baf.append((byte) current);
                    }

                    FileOutputStream fos = new FileOutputStream(file);
                    fos.write(baf.toByteArray());
                    fos.close();
                    tv.setText("Download Completed in" + ((System.currentTimeMillis() - startTime) / 1000) + " sec");
            } catch (IOException e) {
            	 tv.setText("Error: " + e);
            }
    }
}

AndroidManifest.xml

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
      package="pack.coderzheaven"
      android:versionCode="1"
      android:versionName="1.0">

        <uses-permission android:name="android.permission.INTERNET"></uses-permission>
        <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"></uses-permission>
        <uses-permission android:name="android.permission.READ_PHONE_STATE"></uses-permission>


    <application android:icon="@drawable/icon" android:label="@string/app_name">
        <activity android:name=".DownloadImage"
                  android:label="@string/app_name">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />
                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    </application>
</manifest>

Strings.xml

<?xml version="1.0" encoding="utf-8"?>
<resources>
    <string name="hello">DownloadImage Demo from CoderzHeaven</string>
    <string name="app_name">DownloadImage</string>
</resources>

Download Image Demo

Download Image Demo

Hi,

In order to make a UITextField a Password Field / Password Mode do the following.

In your .h class file,

IBOutlet UITextField *urPassword;

In your .m class file,

urPassword.secureTextEntry = YES;

This will make your UITextField in a Password entry mode or a Password Field.

Hi,

In order to set the font type of UITextView, do the following.

In your .h class file,

IBOutlet UITextView *urTextView;

In your .m class file,

[urTextViewsetFont:[UIFont fontWithName:@"Arial Rounded MT Bold" size:18]];

This will set ‘urTextView’ with font name ‘Arial Rounded MT Bold’ with font size 18.

Hello all……..
In today’s post I will show you send mail from an android application progrmatically..
Let’s go to the code fast……
This is the code in the mail java file….

package com.coderzheaven;

import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;

public class sendMailDemo extends Activity {
    Button send;
    EditText address, subject, emailbody;
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        address = (EditText) findViewById(R.id.address);
        subject = (EditText) findViewById(R.id.subject);
        emailbody = (EditText) findViewById(R.id.body);
        send = (Button) findViewById(R.id.send);

        send.setOnClickListener(new OnClickListener() {
            @Override
            public void onClick(View v) {
            	sendEmail();
            }
        });
    }

    public void sendEmail(){

    	if(!address.getText().toString().trim().equalsIgnoreCase("")){
    	  final Intent emailIntent = new Intent(android.content.Intent.ACTION_SEND);
	      emailIntent.setType("plain/text");
	      emailIntent.putExtra(android.content.Intent.EXTRA_EMAIL, new String[]{ address.getText().toString()});
	      emailIntent.putExtra(android.content.Intent.EXTRA_SUBJECT, subject.getText());
	      emailIntent.putExtra(android.content.Intent.EXTRA_TEXT, emailbody.getText());
	      sendMailDemo.this.startActivity(Intent.createChooser(emailIntent, "Send mail..."));
	    }
    	else{
    		Toast.makeText(getApplicationContext(), "Please enter an email address..", Toast.LENGTH_LONG).show();
    	}
      }
	}

Now the layout file (main.xml)

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout android:id="@+id/LinearLayout01" android:layout_width="fill_parent"
	android:layout_height="fill_parent"
	xmlns:android="http://schemas.android.com/apk/res/android"
	android:orientation="vertical"
	android:background="@drawable/android"
	>
	<TextView
		android:layout_width="wrap_content"
		android:layout_height="wrap_content"
		android:id="@+id/emailaddress"
		android:text="Email Address"
		android:textStyle="bold">
	</TextView>

	<EditText
		android:layout_width="wrap_content"
		android:layout_height="wrap_content"
		android:width="250dip"
		android:hint="email address"
		android:id="@+id/address">
	</EditText>

	<TextView
		android:layout_width="wrap_content"
		android:layout_height="wrap_content"
		android:text="Subject"
		android:textStyle="bold">
	</TextView>

	<EditText
		android:layout_width="wrap_content"
		android:layout_height="wrap_content"
		android:width="250dip"
		android:hint="Subject"
		android:id="@+id/subject">
	</EditText>

	<TextView
		android:layout_width="wrap_content"
		android:layout_height="wrap_content"
		android:text="Your Message"
		android:textStyle="bold">
	</TextView>
	<EditText
		android:layout_width="fill_parent"
		android:layout_height="wrap_content"
		android:lines="5"
		android:hint="Your message here!!"
		android:id="@+id/body">
	</EditText>
	<Button
		android:layout_width="wrap_content"
		android:layout_height="wrap_content"
		android:id="@+id/send"
		android:text="Send Email"
		android:width="150dip">
	</Button>
</LinearLayout>

The AndroidManifest.xml

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
      package="com.coderzheaven"
      android:versionCode="1"
      android:versionName="1.0">
    <application android:icon="@drawable/icon" android:label="Send Mail Demo">
        <activity android:name=".sendMailDemo"
                  android:label="Send Mail Demo">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />
                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    </application>
</manifest>

Note: However if you test this in your emulator, it will not work. Install it in your device to test it.