UIScrollView - scale all routines inside (not only)

Question

Good evening!

I am trying to increase the UIScrollView, more specifically all the subviews placed inside.

As far as I understand, I need to implement the UIScrollViewDelegate method:

func viewForZoomingInScrollView(scrollView: UIScrollView) -> UIView? {
    return subView // <--- subview inside my scroll view
}

In my test projects, the increase just won't work until I do this. But using this technique, I can only increase (1) a single view. There are dozens of subviews in my scroll that I also want to increase. I can solve this by placing one UIView inside a UIScrollView and then other subviews inside this container view, but I would like to ask if there is a better solution?

I used both the automatic pinch mechanism to increase scrollview, and later played with my own recognizing gesture:

override func viewDidLoad() {
    super.viewDidLoad()
...
    let pinchGesture = UIPinchGestureRecognizer(target: self, action: "pinchHandler:")

    scrollView.addGestureRecognizer(pinchGesture)
.
.
.
func pinchHandler(recognizer: UIPinchGestureRecognizer)
{
    if recognizer.state == UIGestureRecognizerState.Began
    {
        if recognizer.scale < 1.0 {
            scrollView.setZoomScale(1, animated: true)                
        } else {
            scrollView.setZoomScale(2, animated: true)                
        }                       
    }
}

1 ( viewForZoomingInScrollView)

.