问当用户按下Android自定义相机上的后退按钮时，如何停止录像？

EN

@Override
public void onBackPressed() {
  if (mMediaRecorder != null) {
   //Wtire your code for stop video, on back press
    mMediaRecorder.stop();
    mMediaRecorder.reset();
   }else{
    super.onBackPressed();
   }         
}

public interface IOnBackPressed {
/**
 * If you return true the back press will not be taken into account, otherwise the activity will act naturally
 * @return true if your processing has priority if not false
 */
boolean onBackPressed();
}

public class MyActivity extends Activity {
@Override public void onBackPressed() {
Fragment fragment = getSupportFragmentManager().findFragmentById(R.id.main_container);
   if (!(fragment instanceof IOnBackPressed) || !((IOnBackPressed) fragment).onBackPressed()) {
      super.onBackPressed();
   }
 } 
}

public class MyFragment extends Fragment implements IOnBackPressed{
@Override
public boolean onBackPressed() {
   if (myCondition) {
        if (mMediaRecorder != null) {
         //Wtire your code for stop video, on back press
         mMediaRecorder.stop();
         mMediaRecorder.reset();
        }
      return true; 
    } else {
        return false;
    }
 }
}