一次仅显示一个视图，以便用户可以在视图之间切换

Question

问题：

我有3个单独的视图，我一次要显示所有视图，但我只希望一次显示一个视图，以便用户可以在这三个视图之间切换。这是现在正在发生的事情。

代码在下面很长，但是如果您将代码复制并粘贴到Xcode中，则可以看到现在发生了什么。我有三个具有不同大小框架的视图。您可以单击每个视图按钮，它将打开该视图。

import SwiftUI

struct ContentView: View {
    @State var show1 = false
    @State var show2 = false
    @State var show3 = false

    var body: some View {
                ZStack {
                          NavigationView {
                            VStack {
                                Section {
                                    Color(red: 0.88, green: 0.88, blue: 0.88)
                                    .frame(maxWidth: .infinity, maxHeight: .infinity).edgesIgnoringSafeArea(.all)
                                 HStack {

                                    Button(action: {
                                        withAnimation(.spring())
                                        {
                                            self.show1.toggle()
                                        }
                                    }) {
                                        Text("View1")
                                            .font(.headline)
                                            .fontWeight(.regular)
                                            .lineLimit(nil)
                                            .padding(EdgeInsets.init(top: -5, leading: 15, bottom: 0, trailing: 15))
                                        .foregroundColor(show1 ? .blue : .gray)
                                    }.foregroundColor(show1 ? .blue : .gray)
                                    .padding()


                                    Button(action: {
                                        withAnimation(.spring())
                                        {
                                    self.show2.toggle()
                                    }
                                    }) {
                                            Text("View2")
                                            .font(.headline)
                                            .fontWeight(.regular)
                                            .lineLimit(nil)
                                            .padding(EdgeInsets.init(top: -5, leading: 15, bottom: 0, trailing: 15))
                                        .foregroundColor(show2 ? .blue : .gray)

                                    }.foregroundColor(show2 ? .blue : .gray)
                                    .padding()


                                    Button(action: {
                                          withAnimation(.spring())
                                          {
                                      self.show3.toggle()
                                      }
                                      }) {
                                        Text("View3")
                                            .font(.headline)
                                            .fontWeight(.regular)
                                            .lineLimit(nil)
                                            .padding(EdgeInsets.init(top: -5, leading: 15, bottom: 0, trailing: 10))
                                        .foregroundColor(show3 ? .blue : .gray)

                                    }.foregroundColor(show3 ? .blue : .gray)
                                .padding()
                                    }}}
                    }
                            VStack (alignment: .center) {
                    if self.show1 {
                        ShowView1().transition(
                            AnyTransition.move(edge: .bottom).combined(with: .move(edge: .bottom)).combined(with: .opacity))
                            }
                            }

                    VStack (alignment: .center) {
                            if self.show2 {
                                 ShowView2().transition(
                                    AnyTransition.move(edge: .bottom).combined(with: .move(edge: .bottom)).combined(with: .opacity))
                            }
                    }

                    VStack (alignment: .center) {
                            if self.show3 {
                                 ShowView3().transition(
                                    AnyTransition.move(edge: .bottom).combined(with: .move(edge: .bottom)).combined(with: .opacity))
                            }
                    }}}}


struct ShowView1: View {
    var body: some View {
        ZStack() {
            Color.white
                .frame(maxWidth: .infinity, maxHeight: 52)
            }

        }
    }

struct ShowView2: View {
    var body: some View {
        ZStack() {
            Color.white
                .frame(maxWidth: .infinity, maxHeight: 600)

            }
        }
    }

struct ShowView3: View {
     var body: some View {
         ZStack() {
             Color.white
                 .frame(maxWidth: .infinity, maxHeight: 300)
             }
         }
     }

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

Answer 1

实际上，您不是在切换而是切换每个视图，因此导致视图共存。这是代码的更正部分（仅开关逻辑）。在Xcode 11.2 / iOS 13.2上进行了测试。

struct ContentView: View {
    @State var selectedView: Int? = nil

    var body: some View {
        ZStack {
            NavigationView {
                VStack {
                    Section {
                        Color(red: 0.88, green: 0.88, blue: 0.88)
                            .frame(maxWidth: .infinity, maxHeight: .infinity).edgesIgnoringSafeArea(.all)
                        HStack {

                            Button(action: {
                                withAnimation(.spring())
                                {
                                    self.selectedView = 1
                                }
                            }) {
                                Text("View1")
                                    .font(.headline)
                                    .fontWeight(.regular)
                                    .lineLimit(nil)
                                    .padding(EdgeInsets.init(top: -5, leading: 15, bottom: 0, trailing: 15))
                                    .foregroundColor(self.selectedView == 1 ? .blue : .gray)
                            }.foregroundColor(self.selectedView == 1 ? .blue : .gray)
                                .padding()


                            Button(action: {
                                withAnimation(.spring())
                                {
                                    self.selectedView = 2
                                }
                            }) {
                                Text("View2")
                                    .font(.headline)
                                    .fontWeight(.regular)
                                    .lineLimit(nil)
                                    .padding(EdgeInsets.init(top: -5, leading: 15, bottom: 0, trailing: 15))
                                    .foregroundColor(self.selectedView == 2 ? .blue : .gray)

                            }.foregroundColor(self.selectedView == 2 ? .blue : .gray)
                                .padding()


                            Button(action: {
                                withAnimation(.spring())
                                {
                                    self.selectedView = 3
                                }
                            }) {
                                Text("View3")
                                    .font(.headline)
                                    .fontWeight(.regular)
                                    .lineLimit(nil)
                                    .padding(EdgeInsets.init(top: -5, leading: 15, bottom: 0, trailing: 10))
                                    .foregroundColor(self.selectedView == 3 ? .blue : .gray)

                            }.foregroundColor(self.selectedView == 3 ? .blue : .gray)
                                .padding()
                        }}}
            }
            VStack (alignment: .center) {
                if self.selectedView == 1 {
                    ShowView1().transition(
                        AnyTransition.move(edge: .bottom).combined(with: .move(edge: .bottom)).combined(with: .opacity))
                }

                if self.selectedView == 2 {
                    ShowView2().transition(
                        AnyTransition.move(edge: .bottom).combined(with: .move(edge: .bottom)).combined(with: .opacity))
                }

                if self.selectedView == 3 {
                    ShowView3().transition(
                        AnyTransition.move(edge: .bottom).combined(with: .move(edge: .bottom)).combined(with: .opacity))
                }
            }}}}