Hi,

I noticed that Navigationbar- / Toolbar Buttons are not working properly when there is at least one @State variable refreshing the View very often.

I created a simple app to test it.

With below Code example you have 3 options to trigger a modal sheet. One Button in the main View, one in the toolbar and one in the navigationbar.

When my timer doesn't update "number" all 3 buttons are working properly. When i start the Timer which will refresh the view every 0,1 second only the button in the main view will work every time. The buttons in toolbar / navigationbar do not work most of the time. (The shorter the TimeInterval of my timer the less the buttons are working)

import SwiftUI

struct ContentView: View {

    @State private var number = 0
    @State private var showModal = false

    func startTimer() {
        Timer.scheduledTimer(withTimeInterval: 0.1, repeats: true) { (_) in
            number += 1
        }
    }

    var body: some View {

        NavigationView {
            VStack {
                Text("Count \(number)")
                Button(action: startTimer, label: {
                    Text("Start Timer")
                })

                Button(action: { showModal.toggle() }, label: {
                    Text("Open Modal")
                })
            }
            .navigationBarTitle("Home", displayMode: .inline)
            .navigationBarItems(leading:
                                    Button(action: {
                                        showModal.toggle()
                                    }, label: {
                                        Text("Open Modal")
                                    }))

            .toolbar {
                ToolbarItem(placement: .bottomBar) {
                    Button(action: {
                        showModal.toggle()
                    }, label: {
                        Text("Open Modal")
                    })
                }
            }
        }

        .sheet(isPresented: $showModal, content: {
            Text("Hello, World!")
        })

    }
}

Does anyone have an idea if there is a way to make the 2 buttons work properly?

I'm afraid I don't have a solution but I can confirm that I'm seeing the same thing. In my app I have a button in a toolbar located in the navigation bar, the button pushes a new view onto the navigation stack. The button usually doesn't work. Putting another button outside of the toolbar works.

My app constantly updates its main view with new information. I have a button to pause the updates and if I activate the pause, the button in the toolbar works. If I lower the frequency of the updates it gets easier to successfully press the button. Maybe the time between a button press and release can't be interrupted by a view update?

This seems like a bug in SwiftUI.