Visual Glitch when using *Stack view inside of CarouselStack item view

[1er4y]

Describe the bug
Hi. Thanks for library - very helpful.
Got some issue here and can't solve few days
I'm trying to create CarouselStack Item view with complex layout but getting visual glitches inside of it

I need to split my layout into few subviews because its complex and contains many Stacks for alignment and content, but can't get it working.

I've created sample project for minimal reproducing, see Additional Context

To Reproduce
Minimum amount of code to reproduce:

ContentView.swift

import SwiftUI
import CarouselStack

struct ContentView: View {
    var ints = [1,2,3,4,5,6,7,8,9]
    var body: some View {
        CarouselStack(ints, initialIndex: 0) { int in
            CustomView(passedInt: int)
        }
        .padding()
    }
}

struct ContentView_Previews: PreviewProvider {
    static var previews: some View {
        ContentView()
    }
}

CustomView.swift

import SwiftUI

struct CustomView: View {
    let passedInt: Int
    var body: some View {
        VStack { //works if replace VStack with Non-Stack view
            if passedInt % 2 == 0 {
                viewOne.padding()
            }
            else {
                viewTwo.padding()
            }

            subscription
                .padding()
        }
        .background(.gray)
    }

    var viewOne: some View {
        Group {
            Text("I like this Int: \(passedInt)")
                .foregroundColor(.yellow)
                .font(.title3)
                .background(content: {
                    ZStack {
                        Color(.blue)
                    }
                })
        }

    }

    var viewTwo: some View {
        Group {
            Text("I dont like this Int: \(passedInt)")
                .foregroundColor(.white)
                .font(.title)
                .background(content: {
                    ZStack {
                        Color(.blue)
                    }
                })

            Text("\(passedInt)")
                .foregroundColor(.white)
                .font(.title)
                .background(content: {
                    ZStack {
                        Color(.green)
                    }
                })
        }
    }

    var subscription: some View {
        VStack {
            Text("Please tell your favorite Int")
                .foregroundColor(.red)
        }

    }
}

struct CustomView_Previews: PreviewProvider {
    static var previews: some View {
        CustomView(passedInt: 1)
    }
}

Steps to reproduce the behavior:

1. Download attached project and run

Expected behavior
Everything works correctly

Screenshots

Device information (please complete the following information):

• Device: Simulator
• OS: 16.2
• Xcode version: 14.2

Additional context
MinimalProject.zip

[dscyrescotti]

@1er4y Thank you for raising this issue with minimum project. 😃

I had a quick look and figured out that SizePreferenceKey is wrongly triggered with CGSize.zero resulting the breakdown of CarouselStack's appearance. So it could be temporarily fixed by skipping CGSize.zero value inside onPreferenceChange(_:_) modifier as follows.

.onPreferenceChange(SizePreferenceKey.self) { size in
    if size != .zero {
        DispatchQueue.main.async {
            self.size = size
        }
    }
}

[1er4y]

I had a quick look and figured out that SizePreferenceKey is wrongly triggered with CGSize.zero resulting the breakdown of CarouselStack's appearance. So it could be temporarily fixed by skipping CGSize.zero value inside onPreferenceChange(_:_) modifier as follows.

.onPreferenceChange(SizePreferenceKey.self) { size in
    if size != .zero {
        DispatchQueue.main.async {
            self.size = size
        }
    }
}

Thank you for workaround - going to apply this as a temporary fix and will wait for fix versions!

@1er4y Thank you for raising this issue with minimum project. 😃

Everything for nice library =)

[dscyrescotti]

The issue is now closed since it has been resolved and the fix is available in Version 2.1.3.