swiftui - 如何在没有导航 View 或弹出窗口的情况下切换 View ？

Question

我试图改变一个 View ，而没有像你在 swift 中使用 segue 时那样。但我想出的唯一解决方案是使用导航栏 navigationBar 或弹出框。

struct view1: View {

    var body: some View{

        Button(action: {
//          go to view2``
        }) {
            Text("press")
        }

    }
}

struct view2: View {

    var body: some View{
       Text("yeay")

    }
}

Answer 1

如果您只想隐藏导航栏，这很容易:

import SwiftUI

struct View2: View {
    @Environment(\.presentationMode) var presentationMode: Binding<PresentationMode>

    var body: some View {
        VStack {
            Button(action: {
                self.presentationMode.wrappedValue.dismiss()
            }) {
                Text("POP")
            }
        }
        .navigationBarTitle("")
        .navigationBarBackButtonHidden(true)
        .navigationBarHidden(true)
    }
}

struct ContentView: View {
    var body: some View {
        NavigationView {
            NavigationLink(destination: View2()) {
                Text("PUSH")
                    .navigationBarTitle("")
                    .navigationBarHidden(true)
            }
        }
    }
}

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

相反，如果您想摆脱 NavigationView和 NavigationLink您必须实现自己的自定义导航。它有点复杂。以下只是两个 View 之间推送/弹出转换的简单示例。

import SwiftUI

struct View2: View {
    @Binding var push: Bool

    var body: some View {
        ZStack {
            Color.yellow
            Button(action: {
                withAnimation(.easeOut(duration: 0.3)) {
                    self.push.toggle()
                }
            }) {
                Text("POP")
            }
        }
        .edgesIgnoringSafeArea(.all)
    }
}

struct View1: View {
    @Binding var push: Bool

    var body: some View {
        ZStack {
            Color.green
            Button(action: {
                withAnimation(.easeOut(duration: 0.3)) {
                    self.push.toggle()
                }
            }) {
                Text("PUSH")
            }
        }
        .edgesIgnoringSafeArea(.all)
    }
}

struct ContentView: View {
    @State private var push = false

    var body: some View {
        ZStack {
            if !push {
                View1(push: $push)
                    .transition(.asymmetric(insertion: .move(edge: .leading), removal: .move(edge: .leading)))
            }

            if push {
                View2(push: $push)
                    .transition(.asymmetric(insertion: .move(edge: .trailing), removal: .move(edge: .trailing)))
            }
        }
    }
}

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