SwiftUI Alertを複数使い分けたい

サンプルアプリ

機能

Toggle Switchのある側のAlertを表示します。

Alert複数使い分け

表示されないコード

「Show Alert 2」は表示されます。
「Show Alert 1」は無反応です。

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import SwiftUI
 
struct ContentView: View {
    @State var showAlert = false
    @State var showAlert1 = false
    @State var showAlert2 = false
 
    var body: some View {
        VStack {
            HStack {
                Text("Alert 1")
                Toggle(isOn: $showAlert) {
                    EmptyView()
                }
                .labelsHidden()
                Text("Alert 2")
            }
            Button(action: {
                if self.showAlert == false {
                    self.showAlert1.toggle()
                }
                else {
                    self.showAlert2.toggle()
                }
            }) {
                Text("Show Alert")
            }
            .alert(isPresented: $showAlert1) {
                Alert(title: Text("Show Alert 1"))
            }
            .alert(isPresented: $showAlert2) {
                Alert(title: Text("Show Alert 2"))
            }
        }
        .padding(8.0)
    }
}
 
struct ContentView_Previews: PreviewProvider {
    static var previews: some View {
        ContentView()
    }
}

表示されるコード

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import SwiftUI
 
struct ContentView: View {
    @State var showAlert = false
    @State var showAlert1and2 = false
 
    var body: some View {
        VStack {
            HStack {
                Text("Alert 1")
                Toggle(isOn: $showAlert) {
                    EmptyView()
                }
                .labelsHidden()
                Text("Alert 2")
            }
            Button(action: {
                self.showAlert1and2.toggle()
            }) {
                Text("Show Alert")
            }
            .alert(isPresented: $showAlert1and2) {
                switch(showAlert) {
                    case false:
                        return Alert(title: Text("Show Alert 1"))
                    case true:
                        return Alert(title: Text("Show Alert 2"))
                }
            }
        }
        .padding(8.0)
    }
}
 
struct ContentView_Previews: PreviewProvider {
    static var previews: some View {
        ContentView()
    }
}

表示されるコード（Toggleがなかった場合）

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import SwiftUI
 
struct ContentView: View {
    @State var showAlert = false
    @State var showAlert1and2 = false
    @State var alert = 1
 
    var body: some View {
        VStack {
            HStack {
                Text("Alert 1")
                Toggle(isOn: $showAlert) {
                    EmptyView()
                }
                .labelsHidden()
                Text("Alert 2")
            }
            Button(action: {
                switch(self.showAlert) {
                    case false:
                        self.alert = 1
                    case true:
                        self.alert = 2
                }
                self.showAlert1and2.toggle()
            }) {
                Text("Show Alert")
            }
            .alert(isPresented: $showAlert1and2) {
                switch(alert) {
                    case 1:
                        return Alert(title: Text("Show Alert 1"))
                    case 2:
                        return Alert(title: Text("Show Alert 2"))
                    default:
                        return Alert(title: Text("Error"))
                }
            }
        }
        .padding(8.0)
    }
}
 
struct ContentView_Previews: PreviewProvider {
    static var previews: some View {
        ContentView()
    }
}

Swift

Posted by shi-n