Ios14 Introducing Errors with @State Bindings

iOS14 introducing errors with @State bindings

It looks like in iOS 14 the sheet(isPresented:content:) is now created beforehand, so any changes made to selectedModel are ignored.

Try using sheet(item:content:) instead:

var body: some View {
    List {
        ...
    }
    .sheet(item: self.$selectedModel) {
        SpeakerDetailView(speaker: $0)
    }
}

and dismiss the sheet using @Environment(\.presentationMode):

struct SpeakerDetailView: View {
    @Environment(\.presentationMode) private var presentationMode
    var speaker: Speaker

    var body: some View {
        Text("Speaker view")
            .onTapGesture {
                presentationMode.wrappedValue.dismiss()
            }
    }
}

Cant get my sheet to display the right information

In iOS 14 sheet(isPresented:content:) is now created beforehand and the view is not refreshed when the $businessSheetPresented changes.

Instead of .sheet(isPresented:content:)

.sheet(isPresented: $businessSheetPresented) {
    if let pressedUser = pressedUser {
        DisplayBusinessSheet(user: pressedUser)
    }
}

you should use .sheet(item:content:)

.sheet(item: $pressedUser) { user in
    DisplayBusinessSheet(user: pressedUser)
}

Note: with the above solution you don't really need businessSheetPresented unless it's used in some other place apart from triggering the sheet.

Displaying a Sheet from multiple options in swiftUI

Here is another approach for your problem which uses sheet(item:content:)

struct ContentView: View {
    @State private var selectedSpeaker: Speaker?
    @State private var selectedMicrophone: Microphone?
    @State private var selectedAmp: Amplifier?
    @State private var showSettingsSheet = false

    var body: some View {
        List {
            settingsSection
            microphonesSection
            // more sections
        }
    }
    
    var settingsSection: some View {
        Button(action: {
            self.showSettingsSheet = true
        }) {
            Text("Settings")
        }
        .sheet(isPresented: self.$showSettingsSheet) {
            SettingsView()
        }
    }
    
    @ViewBuilder
    var microphonesSection: some View {
        Button(action: {
            self.selectedMicrophone = microphones[0]
        }) {
            Text("Mic 1")
        }
        Button(action: {
            self.selectedMicrophone = microphones[1]
        }) {
            Text("Mic 2")
        }
        .sheet(item: self.$selectedMicrophone) {
            MicDetailView(microphone: $0)
        }
    }
}

This way you also don't need enum ActiveSheet.

---

You can always use @Environment(\.presentationMode) to dismiss a sheet, no need to pass the variable to the sheet (as in SettingsView(showSheet: self.$showingSheet)):

struct SettingsView: View {
    @Environment(\.presentationMode) private var presentationMode

    var body: some View {
        Text("SettingsView")
            .onTapGesture {
                presentationMode.wrappedValue.dismiss()
            }
    }
}

@State property value is not retain when called within the sheet(item:) method

I think you're getting caught by the fact that sheet(item:) only re-renders based on item -- not the encapsulating View's @State variables. As long as you explicitly pass isReseting through the item, it will work:

struct Item: Identifiable, Equatable {
    var id = UUID()
    var name:String
    var active:Bool
}

struct ContentView: View {
    
    var items:[Item] = [Item(name: "Oranges", active: true),
                    Item(name: "Apples", active: false),
                    Item(name: "Cookies", active: false) ]
    
    struct SheetItem : Identifiable {
        var item: Item
        var isReseting: Bool
        
        var id: UUID {
            self.item.id
        }
    }
    
    @State private var selectedItem: SheetItem?
    @State private var isReseting: Bool?
        
    var body: some View {
        List{
            ForEach(items){ item in
                HStack{
                    Text(item.name)
                    
                    Button(item.active ? "Reset": "Initiate"){
                        isReseting = true
                        selectedItem = SheetItem(item: item, isReseting: isReseting ?? false)
                    }
                    .padding()
                    .background(item.active ? Color.blue: Color.gray)
                    .foregroundColor(.white)
                    .cornerRadius(30)
                    .frame(width: 100, height: 65)
                }
            }
        }
        .sheet(item: $selectedItem) { item in
            let _ = print("Value in sheet: \(item.isReseting)")
            
            if item.isReseting == true {
                Text("It's reseting!!!")
            } else {
                Text("It's NOT reseting")
            }
        }
    }
}

A second way to accomplish this is explicitly pass a Binding (even though you don't need to mutate it in the sheet), since it will maintain its link to the @State variable:

struct Item: Identifiable{
    var id = UUID()
    var name:String
    var active:Bool
}

struct ContentView: View {
    
    var items:[Item] = [Item(name: "Oranges", active: true),
                    Item(name: "Apples", active: false),
                    Item(name: "Cookies", active: false) ]
    
    @State private var selectedItem: Item?
    @State private var isReseting: Bool?
        
    var body: some View {
        List{
            ForEach(items){ item in
                HStack{
                    Text(item.name)
                    
                    Button(item.active ? "Reset": "Initiate"){
                        selectedItem = item
                        isReseting = true
                        let _ = print("Value after button tap: \(isReseting)")// output: Value after button tap: Optional(true)
                    }
                    .padding()
                    .background(item.active ? Color.blue: Color.gray)
                    .foregroundColor(.white)
                    .cornerRadius(30)
                    .frame(width: 100, height: 65)
                }
            }
        }
        .sheet(item: $selectedItem){ item in
            // I'm expecting isReseting to be true here, but it's nil
            SheetView(isReseting: $isReseting)
        }
    }
}

struct SheetView : View {
    @Binding var isReseting : Bool?
    
    var body: some View {
        let _ = print("Value in sheet: \(isReseting)")// outputs: Value in sheet: nil
        
        if isReseting == true {
            Text("It's reseting!!!")
        }else{
            Text("It's NOT reseting")
        }
    }
}

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