Inform view that alert OK button is clicked in swiftUI - ios

Question

I have created a ViewModifier to show alert with 2 buttons. How to inform my ContentView that OK button is clicked, so that I can perform button action?
Sample code: ShowAlert is my custom ViewModifier
struct ShowAlert: ViewModifier {
#Binding var showingAlert: Bool
let title: String
let message: String
func body(content: Content) -> some View {
content
.alert(isPresented: $showingAlert) { () -> Alert in
Alert(title: Text(title), message: Text(message),
primaryButton: .default (Text("OK")) {
print("OK button tapped")
//How to trigger ok button clicked event to my content view
},secondaryButton: .cancel())
}
}
}
View Implementation
ScrollView {
....
}.navigationBarTitle("Click")
.navigationBarItems(trailing: Button(action: {
self.showAlert = true
}) {
Image(systemName: "lock")
}.modifier(ShowAlert(showingAlert: $showAlert, title: "", message: "Are you sure you want to Logout"))

Answer 1

Here is a demo of solution with passed callback into modifier. Tested with Xcode 11.4 / iOS 13.4.
struct ShowAlert: ViewModifier {
#Binding var showingAlert: Bool
let title: String
let message: String
var callback: () -> () = {} // << here !!
func body(content: Content) -> some View {
content
.alert(isPresented: $showingAlert) { () -> Alert in
Alert(title: Text(title), message: Text(message),
primaryButton: .default (Text("OK")) {
print("OK button tapped")
self.callback() // << here !!
},secondaryButton: .cancel())
}
}
}
// Demo view
struct TestAlertModifier: View {
#State private var showAlert = false
#State private var demoLog = "Wait for alert..."
var body: some View {
NavigationView {
ScrollView {
Text(demoLog)
}.navigationBarTitle("Click")
.navigationBarItems(trailing: Button(action: {
self.showAlert = true
}) {
Image(systemName: "lock")
}.modifier(ShowAlert(showingAlert: $showAlert, title: "",
message: "Are you sure you want to Logout", callback: confirmAlert)))
}
}
private func confirmAlert() {
self.demoLog = "Tapped - OK"
}
}