How To Use Custom ScrollVIew In Swift Ios

CustomScrollViewController.swift
import UIKit

class CustomScrollViewController: UIViewController, UIScrollViewDelegate {
  @IBOutlet var scrollView: UIScrollView!

}
var containerView: UIView!
override func viewDidLoad() {
  super.viewDidLoad()

  // Set up the container view to hold your custom view hierarchy
  let containerSize = CGSize(width: 640.0, height: 640.0)
  containerView = UIView(frame: CGRect(origin: CGPoint(x: 0, y: 0), size:containerSize))
  scrollView.addSubview(containerView)

  // Set up your custom view hierarchy
  let redView = UIView(frame: CGRect(x: 0, y: 0, width: 640, height: 80))
  redView.backgroundColor = UIColor.redColor();
  containerView.addSubview(redView)

  let blueView = UIView(frame: CGRect(x: 0, y: 560, width: 640, height: 80))
  blueView.backgroundColor = UIColor.blueColor();
  containerView.addSubview(blueView)

  let greenView = UIView(frame: CGRect(x: 160, y: 160, width: 320, height: 320))
  greenView.backgroundColor = UIColor.greenColor();
  containerView.addSubview(greenView)

  let imageView = UIImageView(image: UIImage(named: "slow.png"))
  imageView.center = CGPoint(x: 320, y: 320);
  containerView.addSubview(imageView)

  // Tell the scroll view the size of the contents
  scrollView.contentSize = containerSize;

  // Set up the minimum & maximum zoom scales
  let scrollViewFrame = scrollView.frame
  let scaleWidth = scrollViewFrame.size.width / scrollView.contentSize.width
  let scaleHeight = scrollViewFrame.size.height / scrollView.contentSize.height
  let minScale = min(scaleWidth, scaleHeight)

  scrollView.minimumZoomScale = minScale
  scrollView.maximumZoomScale = 1.0
  scrollView.zoomScale = 1.0

  centerScrollViewContents()
}
func centerScrollViewContents() {
  let boundsSize = scrollView.bounds.size
  var contentsFrame = containerView.frame

  if contentsFrame.size.width < boundsSize.width {
    contentsFrame.origin.x = (boundsSize.width - contentsFrame.size.width) / 2.0
  } else {
    contentsFrame.origin.x = 0.0
  }

  if contentsFrame.size.height < boundsSize.height {
    contentsFrame.origin.y = (boundsSize.height - contentsFrame.size.height) / 2.0
  } else {
    contentsFrame.origin.y = 0.0
  }

  containerView.frame = contentsFrame
}

func viewForZoomingInScrollView(scrollView: UIScrollView!) -> UIView! {
  return containerView
}

func scrollViewDidZoom(scrollView: UIScrollView!) {
  centerScrollViewContents()
}