Here is the code
MainActivity.java
import android.app.Activity;
import android.os.Bundle;
import android.support.v4.view.ViewPager;
public class MainActivity extends Activity {
Button b;
private int[] GalImages = new int[] { R.drawable.pic1, R.drawable.pic2,
R.drawable.pic3, R.drawable.pic4, R.drawable.pic5, R.drawable.pic6,
R.drawable.pic7, R.drawable.pic8, R.drawable.pic9,
R.drawable.pic10, R.drawable.pic11, R.drawable.pic12,
R.drawable.pic13, R.drawable.pic14, R.drawable.pic15,
R.drawable.pic16, R.drawable.pic17, R.drawable.pic18,
R.drawable.pic19, R.drawable.pic20,
R.drawable.pic22,
R.drawable.pic24, R.drawable.pic25, };
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
ViewPager viewPager = (ViewPager) findViewById(R.id.view_pager);
ImageAdapter adapter = new ImageAdapter(this, GalImages);
viewPager.setAdapter(adapter);
viewPager.setOnPageChangeListener(new MyPageChangeListener());
b = (Button) findViewById(R.id.btn);
b.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
int id=ListOfID[indexOfImage];
WallpaperManager myWallpaperManager=WallpaperManager.getInstance(getApplicationContext());
myWallpaperManager.setResource(id);
}
});
}
private int indexOfImage = 0;
private class MyPageChangeListener extends
ViewPager.SimpleOnPageChangeListener {
@Override
public void onPageSelected(int position) {
indexOfImage = position;
}
}
}
ImageAdapter.java
import android.content.Context;
import android.support.v4.view.PagerAdapter;
import android.support.v4.view.ViewPager;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ImageView;
public class ImageAdapter extends PagerAdapter {
Context context;
int[] GalImages;
ImageAdapter(Context context, int[] GalImages) {
this.context = context;
this.GalImages = GalImages;
}
@Override
public int getCount() {
return GalImages.length;
}
@Override
public boolean isViewFromObject(View view, Object object) {
return view == ((ImageView) object);
}
@Override
public Object instantiateItem(ViewGroup container, int position) {
ImageView imageView = new ImageView(context);
int padding = context.getResources().getDimensionPixelSize(
R.dimen.activity_vertical_margin);
imageView.setPadding(padding, padding, padding, padding);
imageView.setScaleType(ImageView.ScaleType.CENTER_INSIDE);
imageView.setImageResource(GalImages[position]);
((ViewPager) container).addView(imageView, 0);
return imageView;
}
@Override
public void destroyItem(ViewGroup container, int position, Object object) {
((ViewPager) container).removeView((ImageView) object);
}
}
OnButtonClick write the below function
int id=ListOfID[indexOfImage];
WallpaperManager myWallpaperManager= WallpaperManager.getInstance(getApplicationContext());
myWallpaperManager.setResource(id);