想实现相册浏览的部分功能，有个问题请教一下！！！！

Question

先用了switcher和gallery，后来又想加手势滑动浏览，就又加上了viewfliper，但是结果只有gallery的图片可以触屏滑动浏览，这个是怎么回事啊public class GalleryActivity extends Activity implements OnItemSelectedListener,
ViewFactory,OnGestureListener{
    /** Called when the activity is first created. */
//private Gallery gallery;
    private ImageSwitcher mSwitcher;
    GestureDetector detector;
private ViewFlipper flipper;
    private int[] mimage_s = new int[]
         { R.drawable.image_s_1, R.drawable.image_s_2, R.drawable.image_s_3, R.drawable.image_s_4,
                 R.drawable.image_s_5, R.drawable.image_s_6, R.drawable.image_s_7};    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        requestWindowFeature(Window.FEATURE_NO_TITLE);
        setContentView(R.layout.main);
        detector = new GestureDetector(this);
        mSwitcher = (ImageSwitcher)findViewById(R.id.switcher);
        mSwitcher.setFactory(this);
        mSwitcher.setInAnimation(AnimationUtils.loadAnimation(this, android.R.anim.fade_in));
        mSwitcher.setOutAnimation(AnimationUtils.loadAnimation(this,android.R.anim.fade_out));
        Gallery g = (Gallery)findViewById(R.id.gallery);
        g.setAdapter(new ImageAdapter(this));
        g.setOnItemSelectedListener(this);
        flipper = (ViewFlipper) findViewById(R.id.flipper);
     flipper.addView(getImageView(R.drawable.image_s_1));
     flipper.addView(getImageView(R.drawable.image_s_2));
     flipper.addView(getImageView(R.drawable.image_s_3));
     flipper.addView(getImageView(R.drawable.image_s_4));
     flipper.addView(getImageView(R.drawable.image_s_5));
     flipper.addView(getImageView(R.drawable.image_s_6));
     flipper.addView(getImageView(R.drawable.image_s_7));  
    }    private View getImageView(int id){
     ImageView imgView = new ImageView(this);
     imgView.setImageResource(id);
     return imgView;
    }
    
    @Override
public View makeView() {
// TODO Auto-generated method stub
     ImageView i = new ImageView(this);
     i.setBackgroundColor(0xFF000000);
     i.setScaleType(ImageView.ScaleType.FIT_CENTER);
     i.setLayoutParams(new ImageSwitcher.LayoutParams(
     LayoutParams.FILL_PARENT,LayoutParams.FILL_PARENT));
return i;
} @Override
public void onItemSelected(AdapterView<?> adapter, View v, int position,
long id) {
// TODO Auto-generated method stub
mSwitcher.setImageResource(mimage_s[position]);
} @Override
public void onNothingSelected(AdapterView<?> arg0) {
// TODO Auto-generated method stub

}
@Override
public boolean onTouchEvent(MotionEvent event) {
// TODO Auto-generated method stub
return detector.onTouchEvent(event);
} @Override
public boolean onDown(MotionEvent e) {
// TODO Auto-generated method stub
return false;
} @Override
public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX,
float velocityY) {
// TODO Auto-generated method stub
 if(e1.getX() - e2.getX() > 120){//向右滑动
   flipper.setInAnimation(AnimationUtils.loadAnimation(this, R.anim.push_left_in));
   flipper.setOutAnimation(AnimationUtils.loadAnimation(this, R.anim.push_left_out));
   flipper.showNext();
   return true;
  }else if(e2.getX() - e1.getX() > 120){//向左滑动
   flipper.setInAnimation(AnimationUtils.loadAnimation(this, R.anim.push_right_in));
   flipper.setOutAnimation(AnimationUtils.loadAnimation(this, R.anim.push_right_out));
   flipper.showPrevious();
   return true;
  }
return false;
} @Override
public void onLongPress(MotionEvent e) {
// TODO Auto-generated method stub

} @Override
public boolean onScroll(MotionEvent e1, MotionEvent e2, float distanceX,
float distanceY) {
// TODO Auto-generated method stub
return false;
} @Override
public void onShowPress(MotionEvent e) {
// TODO Auto-generated method stub

} @Override
public boolean onSingleTapUp(MotionEvent e) {
// TODO Auto-generated method stub
return false;
}
public class ImageAdapter extends BaseAdapter{
        public ImageAdapter(Context c)
        {
         mContext = c;
        } @Override
public int getCount() {
// TODO Auto-generated method stub
return mimage_s.length;
} @Override
public Object getItem(int position) {
// TODO Auto-generated method stub
return position;
} @Override
public long getItemId(int position) {
// TODO Auto-generated method stub
return position;
}
//, View convertView, ViewGroup parent
public View getView(int position, View convertView, ViewGroup parent) {
// TODO Auto-generated method stub
ImageView i = new ImageView(mContext); i.setImageResource( mimage_s[position]);
i.setAdjustViewBounds(true);
i.setLayoutParams(new Gallery.LayoutParams(LayoutParams.WRAP_CONTENT,LayoutParams.WRAP_CONTENT));
i.setBackgroundResource(R.drawable.picture_frame);

return i;
}
    private Context mContext;
        }

    }