Animation stops when returns to view using Navigation Bar

[junaidxabd]

If you press back to go back to the view with the animation (in the navigation controller stack) the animation doesn’t work.

[Xopoko]

Same problem, swipe to back, too

[chrismgala]

Having the same problem as well. Tried moving the code from viewDidLoad to viewWillAppear as that is called each time the view is reloaded but didn't help.

[dopefaceee]

anyone resolve the issue ?

[sblatz]

Bump. Also having this issue whenever the view disappears and reappears (like upon minimizing the app and opening again).

[DaveCC94]

I have some kind of workaround, but you may not like it.

In my case I created a subclass from UIButton, then I added the gradient there and unluckily for me I crossed with this issue, so what I did next is to override willMove like this

override func willMove(toWindow newWindow: UIWindow?) {
    if newWindow == nil {
        // We remove the view
        self.subviews[0].removeFromSuperview()
    } else {
        // Add we re-added the Pastel View here
    }
}

I personally don't like to mess with this methods because this can lead to some errors, but in this way we can remove the unmoving view and add it again.

Also, I didn't notice any significant memory leak, it spikes to 0.1MB when displayed and then it gets to 0 as soon as the PastelView is removed.

[Umity]

tried viewdidAppear but didnt help..

[iambenmitchell]

override func viewDidLoad() {
    super.viewDidLoad()
    gradient()
    NotificationCenter.default.addObserver(self, selector: #selector(willEnterForeground), name: UIApplication.willEnterForegroundNotification
        , object: nil)

}

@objc func willEnterForeground() {
    print("test")
    gradient()
}

func gradient(){
    let pastelView = PastelView(frame: view.bounds)

    // Custom Direction
    pastelView.startPastelPoint = .bottomLeft
    pastelView.endPastelPoint = .topRight

    // Custom Duration
    pastelView.animationDuration = 1.5

    // Custom Color
    pastelView.setColors([UIColor(red: 156/255, green: 39/255, blue: 176/255, alpha: 1.0),
                          UIColor(red: 255/255, green: 64/255, blue: 129/255, alpha: 1.0),
                          UIColor(red: 123/255, green: 31/255, blue: 162/255, alpha: 1.0),
                          UIColor(red: 32/255, green: 76/255, blue: 255/255, alpha: 1.0),
                          UIColor(red: 32/255, green: 158/255, blue: 255/255, alpha: 1.0),
                          UIColor(red: 90/255, green: 120/255, blue: 127/255, alpha: 1.0),
                          UIColor(red: 58/255, green: 255/255, blue: 217/255, alpha: 1.0)])

    pastelView.startAnimation()
    view.insertSubview(pastelView, at: 0)
    print("Test1")
}

"Test" and "Test1" is printed to the console, yet the animation refuses to resume