/**
* Get the image that is under the single-touch point, or return null (canceling the drag op) if
* none
*/
public Img getDraggableObjectAtPoint(PointInfo pt) {
float x = pt.getX(), y = pt.getY();
int n = mImages.size();
for (int i = n - 1; i >= 0; i--) {
Img im = mImages.get(i);
if (im.containsPoint(x, y)) return im;
}
return null;
}
