Issue with Animations Blocking Taps in UIView Toasts (SwiftUI + Separate UIWindow)

Question

Created 1w

Replies 2

Boosts 0

Participants 2

Edit: Well this is embarassing. It looks like I didn't research this thoroughly enough, animations block UIVIew tap events. I found a solution by using DispatchQueue

I ran into an unexpected issue when presenting a UIView-based toast inside a separate UIWindow in a SwiftUI app. Specifically, when animations are applied to the toast view (UIToastView), the tap gesture no longer works.

To help identify the root cause, I created a minimal reproducible example (MRE) with under 500 lines of code, demonstrating the behavior:

Demo GIF: Screen Recording
Code Repo: ToastDemo

What I Tried:

Using a separate UIWindow to present the toast overlay.
Adding a tap gesture directly to the UIView.
Referencing related solutions:
- A Blog Post explaining UIWindow usage in SwiftUI - https://www.fivestars.blog/articles/swiftui-windows (Sorry, Apple Dev Forum will not allow a link to this)
- A Stack Overflow thread on handling touch events in multiple windows.

Problem Summary:

When animations are involved (fade in, slide up), taps on the toast are not recognized.
Without animations, taps work as expected.
UIWindow setup seems correct, so I’m wondering if animation effects are interfering with event propagation.

I could potentially work around this by restructuring the touch handling, but I'd love insight from the community on why this happens, or if there’s a cleaner fix.

Edit: Well this is embarassing. It looks like I didn't research this thoroughly enough, animations block UIVIew tap events. I found a solution by using DispatchQueue

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Answer 1

Claude31 OP

1w

Could you post the relevant code for animation (to avoid the need to download the whole project).

Did you enable userInteraction (allowUserInteraction)?

See details here: https://stackoverflow.com/questions/7337363/how-to-recognize-tap-gesture-while-a-view-is-animating

0

Answer 2

mellis94 OP

1w

Accepted Answer

This code has the problem I encountered

    // Fade in and rise up animation
        UIView.animate(withDuration: 0.3, animations: {
            self.alpha = 1
            self.frame.origin.y -= 50
        }) { _ in
            UIView.animate(withDuration: 0.3, delay: duration, animations: {
                
                self.alpha = 0
                self.frame.origin.y += 50 // Moves down
            }) { _ in
                self.removeFromSuperview()
            }
        }

This snippet shows the fix

// Fade in and rise up animation
        UIView.animate(withDuration: 0.3, animations: {
            self.alpha = 1
            self.frame.origin.y -= 50
        }) { _ in
            // This dispatchQueue will allow tap events, it's not acceptable to use the delay parameter from UIView.animate()
            DispatchQueue.main.asyncAfter(deadline: .now() + duration) {
                UIView.animate(withDuration: 0.3, animations: {
                    
                    self.alpha = 0
                    self.frame.origin.y += 50 // Moves down
                }) { _ in
                    self.removeFromSuperview()
                }
            }
        }

0