计时器到期时推送通知？

Question

我正在尝试在正在构建的WatchOS中设置计时器应用程序的推送通知，以防用户将应用程序放置在后台。我已经在初始化中收集了用户的许可，但是我试图使用unotificationRequest来设置本地通知。但是，当我确实设置unotificationRequest时，我会遇到type'（）'的错误我的代码。

我尝试将此请求添加到“导航链接”区域和第二视图控制器区域，这两者都导致我遇到了相同的错误（type'（）'（）'不符合'view'> ） - 为了启用通知的选择是什么？

该代码在下面列出：

import SwiftUI
import UserNotifications

struct ContentView: View {
    @State var secondScreenShown = false
    @State var timerVal = 60
    var body: some View {
        VStack{
            Picker(selection: $timerVal, label: Text("Set Half Time")) {
                Text("1").tag(60)
                Text("2").tag(120)
                Text("20").tag(1200)
                Text("25").tag(1500)
                Text("30").tag(1800)
                Text("35").tag(2100)
                Text("40").tag(2400)
                Text("45").tag(2700)
                
            }
            NavigationLink(destination: SecondView(secondScreenShown: $secondScreenShown, timerVal: timerVal), isActive: $secondScreenShown) {
                Text("Set Half!")
                ///Trying to enable notifications when the user presses "Set Half"
                let center = UNUserNotificationCenter.current()
                
                let content = UNMutableNotificationContent()
                content.title = "Title"
                content.subtitle = "Subtitle"
                
                let trigger = UNTimeIntervalNotificationTrigger(timeInterval: TimeInterval(timerVal), repeats: false)
                
                let request = UNNotificationRequest(identifier: "Identifier", content: content, trigger: trigger)
                
                UNUserNotificationCenter.current().add(request)
                
            }
        }
    }
}
struct SecondView: View {
    @Binding var secondScreenShown: Bool
    @State var timerVal: Int
    @State var stoppage: Int = 60
    @State var overtime: Bool = false
    
    var body: some View {
            VStack{
                if timerVal > 0 || overtime {
                    Text("Time Remaining in Half")
                        .font(.system(size: 14))
                    HStack(spacing: 33){
                        Text("\(timerVal / 60)")
                            .font(.system(size: 40))
                        Text("\(timerVal % 60)")
                            .font(.system(size: 40))
                            .onAppear(){
                                Timer.scheduledTimer(withTimeInterval: 1.0, repeats: true) { inv in
                                    if self.timerVal > 0 {
                                        self.timerVal -= 1
                                        if self.timerVal == 0 {
                                            inv.invalidate()
                                        }
                                    }
                                }
                            }
                        
                    }
                    HStack{
                        Text("Minutes")
                            .font(.system(size: 14))
                        Text("seconds")
                            .font(.system(size: 14))
                    }
                    Button(action: {
                        self.secondScreenShown = false
                    }) {
                        Text("Cancel")
                            .foregroundColor(.red)
                    }
    
                } else {
                    
                    VStack{
                        Picker(selection: $stoppage, label: Text("Add Stoppage Time?")) {
                            Text("1").tag(60)
                            Text("2").tag(120)
                            Text("3").tag(180)
                            Text("4").tag(240)
                            Text("5").tag(300)
                            Text("6").tag(360)
                            Text("7").tag(420)
                            Text("8").tag(480)
                            Text("9").tag(540)
                        }
                        Button(action: {
                            self.timerVal = self.stoppage
                            self.overtime = true
                        }) {
                            Text("Add Stoppage")
                                .foregroundColor(.green)
                        }
                        Button(action: {
                            self.secondScreenShown = false
                        }) {
                            Text("Done")
                                .foregroundColor(.red)
                        }
                        
                    }
                    
            }

            }
    }
    
}





struct ContentView_Previews: PreviewProvider {
    static var previews: some View {
        Group {
            ContentView()
            ContentView()
        }
    }
}

Answer 1

它显示错误，因为您已经在View部分中写下了添加通知代码。

视图仅用于呈现内容，而不是编写动作。

您可以在执行导航时编写以下代码以添加本地通知。

struct ContentViewNotification: View {

    @State var secondScreenShown = false
    @State var timerVal = 60

    var body: some View {
        
        NavigationView {
         
            VStack{
                Picker(selection: $timerVal, label: Text("Set Half Time")) {
                    Text("1").tag(60)
                    Text("2").tag(120)
                    Text("20").tag(1200)
                    Text("25").tag(1500)
                    Text("30").tag(1800)
                    Text("35").tag(2100)
                    Text("40").tag(2400)
                    Text("45").tag(2700)
                    
                }.onChange(of: timerVal) { val in
                    self.secondScreenShown = true
                }
                
                
                NavigationLink(destination: SecondView(secondScreenShown: $secondScreenShown, timerVal: timerVal), isActive: $secondScreenShown) {
                    Text("Set Half!")
                }.simultaneousGesture(TapGesture().onEnded {
                    
                    //Trying to enable notifications when the user presses "Set Half"

                    let center = UNUserNotificationCenter.current()

                    let content = UNMutableNotificationContent()
                    content.title = "Title"
                    content.subtitle = "Subtitle"

                    let trigger = UNTimeIntervalNotificationTrigger(timeInterval: TimeInterval(timerVal), repeats: false)

                    let request = UNNotificationRequest(identifier: "Identifier", content: content, trigger: trigger)

                    UNUserNotificationCenter.current().add(request)
                })
            }
        }
    }
}