touchBegan and TouchEnded overrides are affecting another UIViewController - ios

Question

I have this UIViewController in which i've overrided the touchBegan and touchEnded functions. I also have a button that segueues (push) to another view controller with an SKView on it. But the overrided function in the first controller are still active ei. the calculations done there are still showing on the second ViewController.
Maybe theres something im missing or something im assuming thats wrong. Any help would be appreciated
This is the first view controller
import UIKit
import CoreMotion
class PortraitViewController: UIViewController {
var vc: UIViewController?
var startPoint: CGPoint?
var endPoint: CGPoint?
var movedPoint: CGPoint?
var previousMove = CGPoint(x: 0, y: 0)
var beginTouch: UITouch?
var scaleSum = 0
var isPortrait = true
let DEBUG: Bool = true
// MARK:
// MARK: Overriden Variables
open override var supportedInterfaceOrientations: UIInterfaceOrientationMask{return .portrait}
open override var preferredInterfaceOrientationForPresentation: UIInterfaceOrientation{return .portrait}
override var shouldAutorotate: Bool {return false}
#IBAction func pinch(_ sender: UIPinchGestureRecognizer) {
if (isPortrait){
let scale = sender.scale
scaleSum += scale.exponent
print(scaleSum)
if(scaleSum > 10) {
scaleSum = 0
print(">10")
}
else if(scaleSum < -10) {
print("<10")
}
}
}
override func touchesEnded(_ touches: Set<UITouch>, with event: UIEvent?) {
if(isPortrait){
if let theTouch = touches.first {
endPoint = theTouch.location(in: self.view)
let diffx = (endPoint!.x - startPoint!.x)
let diffy = (endPoint!.y - startPoint!.y)
if(diffx != 0 && diffy != 0){
let vector = CGVector(dx: diffx, dy: diffy)
var angle = atan2(vector.dy, vector.dx) * CGFloat(180.0 / M_PI)
if angle < 0 { angle *= -1 } else { angle = 360 - angle }
}
}
}
super.touchesEnded(touches, with: event)
}
override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {
if(isPortrait){
if let theTouch = touches.first {
startPoint = theTouch.location(in: self.view)
}
}
super.touchesBegan(touches, with: event)
}
//One of my attempts to jerry rig a solution
#IBAction func prepToLandscape(_ sender: UIBarButtonItem) {
self.isPortrait = false
print("isPortrait = \(self.isPortrait)")
}
override func viewDidLoad() {
super.viewDidLoad()
}
override func viewWillAppear(_ animated: Bool) {
navigationController?.setNavigationBarHidden(true, animated: false)
}
}
This is the second view controller
import UIKit
import CoreMotion
import SpriteKit
class LandScapeViewController: UIViewController {
var vc: UIViewController?
// MARK:
// MARK: Overriden Variables
open override var supportedInterfaceOrientations: UIInterfaceOrientationMask{return .landscape}
open override var preferredInterfaceOrientationForPresentation: UIInterfaceOrientation{return .landscapeLeft
// MARK:
// MARK: Functions
override func viewDidLoad() {
super.viewDidLoad()
let controllerStoryBoard = UIStoryboard(name: "Main", bundle: nil)
vc = controllerStoryBoard.instantiateViewController(withIdentifier: "Root")
// Part of my attempt to jerry rig a solution
let vcP: PortraitViewController = UIStoryboard(name:"Controller",bundle: nil).instantiateViewController(withIdentifier: "PortraitController") as! PortraitViewController
vcP.isPortrait = false
print("vcP.isPortrait = \(vcP.isPortrait)")
}
override func viewWillAppear(_ animated: Bool) {
self.view.isMultipleTouchEnabled = true
let scene = GameScene(size: joystickView.bounds.size)
scene.backgroundColor = .gray
if let skView = joystickView as? SKView {
skView.showsFPS = false
skView.ignoresSiblingOrder = true
skView.backgroundColor = .red
skView.presentScene(scene)
}
navigationController?.setNavigationBarHidden(true, animated: false)
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
}
#IBAction func toPortrait(_ sender: UIBarButtonItem) {
self.dismiss(animated: true, completion: {() -> Void in
}
}

Answer 1

Assuming the code shown is everything relevant, this makes sense. What's happening is this: the touch events are hit-tested to the joystickView, but because you haven't implemented a custom touchesBegan(_:with:) on that view, the touch event is passed up to the next UIResponder in the responder chain. That would be the LandScapeViewController. But that class also doesn't implement a custom touchesBegan(_:with:), so the event passes to the next class, which in this case is PortraitViewController. Because PortraitViewController does implement that method, it gets called. There's your confusion.
To fix this, implement the touches… methods on UIResponder for either joystickView or LandScapeViewController, even if they do nothing – but don't call super in them! Note the following, from the touchesBegan(_:with:) documentation:
If you override this method without calling super (a common use pattern), you must also override the other methods for handling touch events, even if your implementations do nothing.
Where you're overriding touchesBegan(_:with:), you probably don't want to call super. This is because the super implementation is the one that says "oh, shoot, I don't know how to handle this – pass it up the chain!" But when you handle the touch, it should end there, because you're handling it! So only call super when you're not handling the touch – which in your case looks like never, at least for PortraitViewController.
For more information, check out Event Delivery: The Responder Chain.