Media Content Provider in Android with Example

package com.example.mediaprovider;
 
import android.app.Activity;
import android.database.Cursor;
import android.net.Uri;
import android.os.Bundle;
import android.provider.MediaStore;
import android.view.Menu;
import android.view.View;
import android.widget.Button;
 
public class MainActivity extends Activity {
 
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        Button but = (Button) findViewById(R.id.buttonret);
        but.setOnClickListener(new View.OnClickListener() {
 
            @Override
            public void onClick(View v) {
                // TODO Auto-generated method stub
                String[] projection = new String[] {
                        MediaStore.Audio.AudioColumns.ALBUM,
                        MediaStore.Audio.AudioColumns.TITLE };
                Uri contentUri = MediaStore.Audio.Media.EXTERNAL_CONTENT_URI;
                Cursor cursor = getContentResolver().query(contentUri,
                        projection, null, null, null);
                // Get the index of the columns we need.
                int albumIdx = cursor
                        .getColumnIndexOrThrow(MediaStore.Audio.AudioColumns.ALBUM);
                int titleIdx = cursor
                        .getColumnIndexOrThrow(MediaStore.Audio.AudioColumns.TITLE);
                // Create an array to store the result set.
                String[] result = new String[cursor.getCount()];
                /*
                 * Iterate over the Cursor, extracting each album name and song
                 * title.
                 */
                while (cursor.moveToNext()) {
                    // Extract the song title.
                    String title = cursor.getString(titleIdx);
                    // Extract the album name.
                    String album = cursor.getString(albumIdx);
                    result[cursor.getPosition()] = title + " (" + album + ")";
                }
                // Close the Cursor.
                cursor.close();
            }
 
        });
    }
 
    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.main, menu);
        return true;
    }
 
}