title: I want to path some data from one activity to another but onActivityResult method doesn't work
body: <p>First I created a class which is called <code>GetMusics.java</code> so i want to path music name to <code>MusicPlater.java</code> class but <code>onActivityResult</code> method doesn't work.I don't know where I am making mistake.</p>
  
  <p>This is <code>GetMusic.java</code> class</p>
  
  <pre><code>public class GetMusics extends ListActivity{
  
  private final String SD_PATH = Environment.getExternalStorageDirectory().getPath();
  List&lt;String&gt; songs = new ArrayList&lt;String&gt;();
  MediaPlayer mp = new MediaPlayer();
  
  class Mp3Filter implements FilenameFilter{
  
      @Override
      public boolean accept(File dir, String filename) {
          // TODO Auto-generated method stub
          return filename.endsWith(".mp3");
      }
  
  }
  @Override
  protected void onCreate(Bundle savedInstanceState) {
      // TODO Auto-generated method stub
      super.onCreate(savedInstanceState);
      setContentView(R.layout.music_layout);
      updateMusicList();
  }
  
  private void updateMusicList(){
      File file = new File(SD_PATH);
      if(file.listFiles(new Mp3Filter()).length&gt;0){
          for(File f : file.listFiles(new Mp3Filter()) ){
              songs.add(f.getName());
          }
      }
      ArrayAdapter&lt;String&gt; adapter = new ArrayAdapter&lt;String&gt;(getApplicationContext(), android.R.layout.simple_dropdown_item_1line,
              songs);
      setListAdapter(adapter);
  }
  
  @Override
  protected void onListItemClick(ListView l, View v, int position, long id) {
      // TODO Auto-generated method stub
      super.onListItemClick(l, v, position, id);
      Intent i = new Intent(GetMusics.this,MusicPlayer.class);
      i.putExtra("song_name", songs.get(position));
      setResult(100,i);
      finish();
  
  }
  </code></pre>
  
  <p>}</p>
  
  <p>and this is MusicPlayer.java class</p>
  
  <pre><code>public class MusicPlayer extends Activity {
  
  MediaPlayer mp = new MediaPlayer();
  
  @Override
  protected void onCreate(Bundle savedInstanceState) {
      // TODO Auto-generated method stub
      super.onCreate(savedInstanceState);
      setContentView(R.layout.music_player);
  }
  
  @Override
  protected void onActivityResult(int requestCode, int resultCode, Intent data) {
      // TODO Auto-generated method stub
      super.onActivityResult(requestCode, resultCode, data);
      if(resultCode==100){
          String song_name = data.getStringExtra("song_name");
          mp.reset();
          try {
              mp.setDataSource(Environment.getExternalStorageDirectory()
                      .getPath() + "/" + song_name);
              mp.prepare();
              mp.start();
          } catch (IllegalArgumentException e) {
              // TODO Auto-generated catch block
              e.printStackTrace();
          } catch (IllegalStateException e) {
              // TODO Auto-generated catch block
              e.printStackTrace();
          } catch (IOException e) {
              // TODO Auto-generated catch block
              e.printStackTrace();
          }
      }
  }
  }
  </code></pre>