UIPanGestureRecognizer - Moving a ball(UIImage) with the pan gesture programmatically

Update: July 8, 2017 (Swift 3.1 + Xcode 8.3.3)
Update: July 18, 2016 (Swift 2.2 + Xcode 7.3.1)
Original Post: June 25, 2015

1. Add an image file named ball.png to the project. 

2. Modify your ViewController.swift as below by enabling either Method 1 or Method 2.

Update: July 8, 2017 (Swift 3.1 + Xcode 8.3.3)

import UIKit

class ViewController: UIViewController {

    

    override func viewDidLoad() {

        super.viewDidLoad()

        

        let myImageView = UIImageView(image: UIImage(named: "ball.png"))

        myImageView.frame = CGRect(x: 100, y: 100, width: 50, height: 50)

        

        myImageView.isUserInteractionEnabled = true

        //Must be enabled for tap events

        

        view.addSubview(myImageView)

        //Add an image programmatically

        

        let myPanGestureRecognizer = UIPanGestureRecognizer(target: self, action: #selector(myPanAction)) //Update: July 18, 2016 for Xcode 7.3.1(Swift 2.2)

        

        myPanGestureRecognizer.minimumNumberOfTouches = 1

        myPanGestureRecognizer.maximumNumberOfTouches = 1

        

        myImageView.addGestureRecognizer(myPanGestureRecognizer)

    }

    

    //Method 1:

    /*func myPanAction(recognizer: UIPanGestureRecognizer) {

        let translation = recognizer.translation(in: self.view)

            if let myView = recognizer.view {

            myView.center = CGPoint(x: myView.center.x + translation.x, y: myView.center.y + translation.y)

        }

            recognizer.setTranslation(CGPoint(x: 0, y: 0), in: self.view)

    }*/

    

    //Method 2:

    func myPanAction(recognizer: UIPanGestureRecognizer) {

        if ((recognizer.state != UIGestureRecognizerState.ended) &&

            (recognizer.state != UIGestureRecognizerState.failed)) {

            recognizer.view?.center = recognizer.location(in: recognizer.view?.superview)

        }

    }

    

    override func didReceiveMemoryWarning() {

        super.didReceiveMemoryWarning()

    }

}

Update: July 18, 2016 (Swift 2.2 + Xcode 7.3.1)

import UIKit

class ViewController: UIViewController {

    override func viewDidLoad() {

        super.viewDidLoad()

        

        let myImageView = UIImageView(image: UIImage(named: "ball.png"))

        myImageView.frame = CGRect(x: 100, y: 100, width: 50, height: 50)

        

        myImageView.userInteractionEnabled = true

        //Must be enabled for tap events

        

        view.addSubview(myImageView)

        //Add an image programmatically

        

        let myPanGestureRecognizer = UIPanGestureRecognizer(target: self, action: #selector(myPanAction)) //Update: July 18, 2016 for Xcode 7.3.1(Swift 2.2)

        

        myPanGestureRecognizer.minimumNumberOfTouches = 1

        myPanGestureRecognizer.maximumNumberOfTouches = 1

        

        myImageView.addGestureRecognizer(myPanGestureRecognizer)

    }

    

    //Method 1:

    /*func myPanAction(recognizer: UIPanGestureRecognizer) {

        let translation = recognizer.translationInView(self.view)

        if let myView = recognizer.view {

            myView.center = CGPoint(x: myView.center.x + translation.x, y: myView.center.y + translation.y)

        }

        recognizer.setTranslation(CGPointZero, inView: self.view)

    } */

    

    //Method 2:

    func myPanAction(recognizer: UIPanGestureRecognizer) {

        if ((recognizer.state != UIGestureRecognizerState.Ended) &&

        (recognizer.state != UIGestureRecognizerState.Failed)) {

            recognizer.view?.center = recognizer.locationInView(recognizer.view?.superview)

        }

    }

    

    override func didReceiveMemoryWarning() {

        super.didReceiveMemoryWarning()

    }

}

Note: you may enable either Method 1 or Method 2.

3. The result: