SwiftUi：通过按钮警报确认导航到辅助页面

Question

我试图弄清楚如何通过按钮警报导航到我的辅助屏幕。首先，用户通过主屏幕中的文本字段输入一些字段。

在此屏幕的底部，用户按下提交按钮，然后会弹出一个警报，询问他们是否希望被带到辅助屏幕或取消不被带到。所有通过主屏幕输入的字段然后都会传递到辅助屏幕。如有必要，用户可以选择在辅助屏幕中导航回主屏幕。

这是我尝试过的：

struct View1: View {
    @State var txtField1 : String = ""
    @State var txtField2: String = ""
    @State var txtField3: String = ""
    @State var txtField4: String = ""
    @State var txtField5 : String = ""
   
    @State private var showingAlert = false
    @State private var showingView = false

    var body: some View {
    HStack{
                    Button(action: {
                        self.showingAlert = true
                    }) {
                        Text("Submit")
                            .alert(isPresented:$showingAlert) {
                                Alert(title: Text("Would you like to go to second screen?"), message: Text("The second screen will pass all data from the first screen."), primaryButton:.destructive(Text("Continue")){
                                    self.showingView = true
                                    }, secondaryButton: .cancel(Text("Cancel")))
                        }
                    }
                }.popover(isPresented: $showingView){
                    NavigationView{
                        View2(txtField1: self.$txtField1, txtField2: self.$txtField2, txtField3: self.$txtField4, txtField5: self.$txtField5)
                      
                    }

}

使用上面的代码时，它会导航到我的辅助屏幕 (View2)，但它就像一张纸。 View2 没有返回 View1 的导航属性，这就是我想要实现的。非常感谢您对此事的任何帮助，谢谢！

Answer 1

要获得Back 按钮，您需要NavigationLink 与popover。您可以“隐藏”NavigationLink 旁边的 Button

import SwiftUI

struct ConfirmNavView: View {
    @State var txtField1 : String = ""
    @State var txtField2: String = ""
    @State var txtField3: String = ""
    @State var txtField4: String = ""
    @State var txtField5 : String = ""
    
    @State private var showingAlert = false
    @State private var showingView = false
    
    var body: some View {
        NavigationView{
            HStack{
                Button(action: {
                    self.showingAlert = true
                }) {
                    Text("Submit")
                        .alert(isPresented:$showingAlert) {
                            Alert(title: Text("Would you like to go to second screen?"), message: Text("The second screen will pass all data from the first screen."), primaryButton:.destructive(Text("Continue")){
                                self.showingView = true
                            }, secondaryButton: .cancel(Text("Cancel")))
                        }
                }
                
                NavigationLink("View2", destination: View2(txtField1: self.$txtField1,
                                                           txtField2: self.$txtField2,
                                                           txtField3: self.$txtField3,
                                                           txtField4: self.$txtField4,
                                                           txtField5: self.$txtField5), isActive: $showingView).hidden().frame(width: 0, height: 0)
            }
        }
        
    }
}
struct View2: View {
    @Binding var txtField1 : String
    @Binding var txtField2: String
    @Binding var txtField3: String
    @Binding var txtField4: String
    @Binding var txtField5 : String
    var body: some View {
        VStack{
            TextField("txtField1", text: $txtField1)
            TextField("txtField2", text:$txtField2)
            TextField("txtField3", text:$txtField3)
            TextField("txtField4", text:$txtField4)
            TextField("txtField5", text:$txtField5)
        }
    }
}
struct ConfirmNavView_Previews: PreviewProvider {
    static var previews: some View {
        ConfirmNavView()
    }
}