Manipulating Android Wallpaper

I searched on how you could manipulate the current wallpaper of the android mobile and here it is the code:

AndroidManifest.xml

<uses-permission name="android.permission.SET_WALLPAPER">

main.xml

<?xml version="1.0" encoding="utf-8"?>
<framelayout android="http://schemas.android.com/apk/res/android" layout_width="wrap_content" layout_height="wrap_content">
<imageview layout_width="wrap_content" layout_height="wrap_content" id="@+id/imageview">
<linearlayout orientation="horizontal" layout_width="wrap_content" layout_height="fill_parent">
<button id="@+id/randomize" layout_width="wrap_content" layout_height="wrap_content" text="@string/randomize" layout_gravity="bottom">
</button><button id="@+id/setwallpaper" layout_width="wrap_content" layout_height="wrap_content" text="@string/set_wallpaper" layout_gravity="bottom">



SetWallpaperActivity.java
package com.kites.sarath.wallpaperdemo;

import android.app.Activity;
import android.os.Bundle;
import java.io.IOException;
import android.app.WallpaperManager;
import android.graphics.Color;
import android.graphics.PorterDuff;
import android.graphics.drawable.Drawable;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.ImageView;

public class SetWallpaperActivity extends Activity {
final static private int[] mColors =
{Color.BLUE, Color.GREEN, Color.RED, Color.LTGRAY, Color.MAGENTA, Color.CYAN,
Color.YELLOW, Color.WHITE};
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
final WallpaperManager wallpaperManager = WallpaperManager.getInstance(this);
final Drawable wallpaperDrawable = wallpaperManager.getDrawable();
final ImageView imageView = (ImageView) findViewById(R.id.imageview);
imageView.setDrawingCacheEnabled(true);
imageView.setImageDrawable(wallpaperDrawable);

Button randomize = (Button) findViewById(R.id.randomize);
randomize.setOnClickListener(new OnClickListener() {
public void onClick(View view) {
int mColor = (int) Math.floor(Math.random() * mColors.length);
wallpaperDrawable.setColorFilter(mColors[mColor], PorterDuff.Mode.MULTIPLY);
imageView.setImageDrawable(wallpaperDrawable);
imageView.invalidate();
}
});

Button setWallpaper = (Button) findViewById(R.id.setwallpaper);
setWallpaper.setOnClickListener(new OnClickListener() {
public void onClick(View view) {
try {

wallpaperManager.setBitmap(imageView.getDrawingCache());
finish();
} catch (IOException e) {
e.printStackTrace();
}
}
});

}
}