OnGestureListener

If you try my sample, you need image and import image at res/drawable-hdpi .

I try onGestureListener interface.
I prepare GestureDetector.

mGestureDetector = new GestureDetector(this, this);

I input onTouchEvent parameter.

public boolean onTouchEvent(MotionEvent ev) {
 mGestureDetector.onTouchEvent(ev);
 return false;
}

I prepare onFling at onGestureListener.

public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX, float velocityY) {

If velocityY smaller than 0, next page.

if (velocityY < 0) {//right
 mPagenumber++;

If velocityY bigger than 0, prev page.

}else {//left
 mPagenumber--;

select image from Resource. I prepare image name "sxxx.jpg". xxx is number. exsapme s001.jpg, s002.jpg, s003.jpg....s020.jpg...
I set selected image to view.

Resources res = getResources();
int resid = res.getIdentifier(filename, "drawable", getPackageName());
ImageView img = (ImageView)findViewById(R.id.imageView1);
img.setImageResource(resid);

source code is here. Please suggest your android issue by twitter or mail, I would try to clear up your issue.