When dragging an image, dont allow the image off screen
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I currently have an imageView which I can drag around the screen using a panGestureRecognizer and the following method:

     - (void)panDetected:(UIPanGestureRecognizer *)panRecognizer {
    CGPoint translation = [panRecognizer translationInView:self.view];
    CGPoint imageViewPosition = self.imageView.center;
    imageViewPosition.x += translation.x;
    imageViewPosition.y += translation.y;
    
    self.imageView.center = imageViewPosition;
    [panRecognizer setTranslation:CGPointZero inView:self.view]; }

Currently the image can be dragged off the screen so that it is only partially visible, I would like to know if there is a way to stop the image at the edge of the screen?  I know it should be possible, I am just struggling with the logic.  Thanks in advance



