UIPinchGestureRecognizer for zooming and panning an image in xcode

Question

I have created one application in which there is one view containing an image view. Below code for zooming an image using UIPinchGestureRecognizer is working. Here innerview is

Answer 1

Embed your innerView in Scroll View Once you are done with pinching, you can get size of new image and then set its content size

-(void)scale:(id)sender {
  if([(UIPinchGestureRecognizer*)sender state] == UIGestureRecognizerStateEnded) {
    lastScale = 1.0;
    CGSize zoomViewSize = CGSizeApplyAffineTransform(imgScrollView.frame.size, [(UIPinchGestureRecognizer *)sender view].transform);
    CGPoint centerPoint = CGPointApplyAffineTransform(imgScrollView.frame.origin, [(UIPinchGestureRecognizer *)sender view].transform);

    CGRect r = imgScrollView.bounds;
    CGSize scrollViewSize = imgScrollView.frame.size;
    imgScrollView.contentSize = zoomViewSize;
    imgScrollView.contentOffset = centerPoint; 
  }

  CGFloat currentScale = [[[(UIPinchGestureRecognizer*)sender view].layer valueForKeyPath:@"transform.scale"] floatValue];

  CGFloat scale = 1.0 - (lastScale - [(UIPinchGestureRecognizer*)sender scale]);
  scale = MIN(scale, imgScrollView.maximumZoomScale / currentScale);   
  scale = MAX(scale, imgScrollView.minimumZoomScale / currentScale);
  CGAffineTransform currentTransform = [(UIPinchGestureRecognizer*)sender view].transform;
  CGAffineTransform newTransform = CGAffineTransformScale(currentTransform, scale, scale);
  [[(UIPinchGestureRecognizer*)sender view] setTransform:newTransform];
  lastScale = [(UIPinchGestureRecognizer*)sender scale];    
}

Hope this help you :)

Answer 2

try this

 -(void)scale:(id)sender {


    if([(UIPinchGestureRecognizer*)sender state] == UIGestureRecognizerStateBegan) {
        _lastScale = 1.0;
    }

    CGFloat scale = 1.0 - (_lastScale - [(UIPinchGestureRecognizer*)sender scale]);
    CGAffineTransform currentTransform = self.transform;
    CGAffineTransform newTransform = CGAffineTransformScale(currentTransform, scale, scale);

    [self setTransform:newTransform];


}