title: Android simple app doesn't start and do not know why
body: <p>I have a problem regarding this simple program (actualy this is the single Activity/Class). This doesn't return me any error, it's simply doesn't start in emulator/device when run it.
  It contains a seekBar(Ringer Volume Bar) and a OK button (to save the changes after seeking the Bar). I don't want a real-time seekBar(I mean when seek in the seekBar, automaticaly change the volume)</p>
  
  <p>This is the code</p>
  
  <pre><code>public class Vol extends Activity {
  
  public static final String TYPE = "TYPE";
  
  
  @Override
  public void onCreate(Bundle savedInstanceState) {
      super.onCreate(savedInstanceState);
  
      Bundle extras  = getIntent().getExtras();
      final int volumeType = extras != null ? extras.getInt(TYPE) : -1;
      final AudioManager audio = (AudioManager) getSystemService(Context.AUDIO_SERVICE);
      String title = "Unknown Volume";
  
      if (volumeType != -1) {
          switch(volumeType) {
          case AudioManager.STREAM_RING:
  
              break;
          }
  
          setContentView(R.layout.main);
          setTitle(title);
          final SeekBar systemSeek = (SeekBar) findViewById(R.id.volume_bar);
          systemSeek.setMax(audio.getStreamMaxVolume(volumeType));
          systemSeek.setProgress(audio.getStreamVolume(volumeType));
          systemSeek.setOnSeekBarChangeListener(new OnSeekBarChangeListener() {
  
              public void onStopTrackingTouch(SeekBar seekBar) {
                  final int setVolFlags = AudioManager.FLAG_PLAY_SOUND | AudioManager.FLAG_SHOW_UI;
                  audio.setStreamVolume(volumeType,seekBar.getProgress(), setVolFlags);
  
              }
  
              public void onStartTrackingTouch(SeekBar seekBar) {
                  // TODO Auto-generated method stub
  
              }
  
              public void onProgressChanged(SeekBar seekBar, int progress,
                      boolean fromUser) {
                  // TODO Auto-generated method stub
  
              }
          });
  
          Button ok  = (Button) findViewById(R.id.ok_button);
          ok.setOnClickListener(new OnClickListener() {
  
              public void onClick(View v) {
                  if (volumeType == AudioManager.STREAM_RING){
                      audio.setRingerMode(AudioManager.RINGER_MODE_NORMAL);
                  }
                  finish();
  
              }
          });
  
      } else {
          finish();
  
      }
  
  }
  </code></pre>
  
  <p>}</p>
  
  <p>Could you please help me? 
  Thanks in advance!</p>