Swiftui：通过函数以编程方式显示警报弹出窗口

如何解决Swiftui：通过函数以编程方式显示警报弹出窗口

我有一个可以在我的应用程序中的几个不同位置调用的函数。

实质上，它检查通知授权状态的状态。如果它是“授权的”，就可以了，该功能什么也不做。如果未确定，则提示用户进行授权。因为没有通知权限，该应用程序将无法100％正常运行，所以我想提醒用户，这是必需的。一切都按计划进行，只是试图找出一种方法来向用户发出警报（即转到“设置”>“通知”>“），或直接定向到应用程序中的另一个页面。

我尝试通过在函数中调用该页面来定向页面，并尝试直接在函数中显示警报，但是据我了解，这两个选项都必须与视图绑定。

该应用在首次启动和安装时会要求获得通知权限，因此大多数问题都不是问题。但是，为了保护我，我想做以上事情。

编辑/更新：

import SwiftUI

struct ContentView: View {

@State var showAlert = false

// FUNCTION: Ask for Notification Permissions
func notificationPermissions() {
UNUserNotificationCenter.current().getNotificationSettings { (settings) in
    if settings.authorizationStatus == .authorized {
        // Notifications are authorized
        print("Notifications are AUTHORIZED")
    }
    else if settings.authorizationStatus == .denied {
        // ALERT: Notifications are denied
        print("ALERT: Notifications are DENIED")
        self.showAlert = true
        print(self.showAlert) // Even though above it is set to true,the print statement says false,the alert doesn't display
    }
    else {
        // Notifications are notDetermined
        print("Notifications are NOTDETERMINED")
        UNUserNotificationCenter.current().requestAuthorization(options: [.alert,.badge,.sound]) { success,error in
            if success {
                print("User has accepted Notification Permissions")
            } else if let error = error {
                print(error.localizedDescription)
            }
        }
    }
}
}

// FUNCTION: Display Notification Reminder Alert
func notificationReminder() -> Alert {
Alert(
    title: Text("Notifications Required"),message: Text("Please authorize notifications by going to Settings > Notifications > Remindr"),dismissButton: .default(Text("Okay")))
}

从另一个角度看...

struct newRemindr: View {

// Alert Control
@Binding var showAlert: Bool

@State var notification = ""
var contentView = ContentView()

// View Controller
var body: some View {
NavigationView {
    Form {
        TextField("Write your notification...",text: $notification)
        
        Button(action: {
            self.contentView.notificationPermissions() // Calls the function above from the content view
        }) {
            Text("Submit")
        }
        
    }
}
}

解决方法

您可以在应用程序的alert（根视图）中使用ContentView修饰符。

struct ContentView: View {
    // pass this var as binding to other views
    @State var showAlert = false
    
    func notificationReminder() -> Alert {
            Alert(
                title: Text("Notifications Required"),message: Text("Please authorize notifications by going to Settings > Notifications > Remindr"),dismissButton: .default(Text("Okay")))
    }
    
    var body: some View {
        
        VStack {
            Text("this is my main view")
        }
        .alert(isPresented: self.$showAlert,content: { self.notificationReminder() })
        
    }
    
}

您可以在应用程序的任何位置显示该警报。您只需将showAlert设置为true。