SwiftUI仅在查看ContentView时隐藏导航栏

时间:2020-06-03 22:29:20

标签: swift swiftui navigationbar navigationview

我有一个内容文件,并且正在隐藏导航栏,因为它占用空间并向下推元素。 ContentView中的一个按钮将重定向(使用导航链接)到另一个视图。在另一个视图中,navigationBar仍处于隐藏状态。...为简单起见,我将从ContentView中剪切一些代码:

//this is the view that looks "fine" (i.e. the navigation bar takes up no space)
struct ContentView: View {
    @State private var isPresentedSettings = false
    var body: some View {
        NavigationView {
            ZStack {
                VStack {
                    SettingsButton(isPresentedSettings: $isPresentedSettings)
                }
            }.navigationBarTitle("").navigationBarHidden(true)
        }
    }
}

//this is the button that pulls up the settings page view
struct SettingsButton: View {
    @Binding var isPresentedSettings: Bool
    var body: some View {
        NavigationLink (destination: SettingsPageView(isPresentedSettings: 
        self.$isPresentedSettings)) {
            Button(action: { self.isPresentedSettings.toggle() }, label: { Text("Button") })
        }
    }
}

//This is the view that should have a navigationbar but it doesn't
struct SettingsPageView: View {
    @Binding var isPresentedSettings: Bool
    var body: some View {
        NavigationView {
            VStack {
                Text("This is a view")
            }.navigationBarTitle("Settings", displayMode: .inline)
        }
    }
}

此外...可能是拼写错误,因为我只是从另一台计算机复制了代码。抱歉,谢谢你!

1 个答案:

答案 0 :(得分:1)

首先,您不需要使用此isPresentedSettings变量即可显示NavigationLink

NavigationLink(destination: SettingsPageView()) {
    Text("Button")
}

视图层次结构中应该只有一个NavigationView

这是您最终代码的样子:

struct ContentView: View {
    @State private var navBarHidden = true

    var body: some View {
        NavigationView {
            ZStack {
                VStack {
                    SettingsButton(navBarHidden: $navBarHidden)
                }
            }
            .navigationBarHidden(navBarHidden)
        }
    }
}
struct SettingsButton: View {
    @Binding var navBarHidden: Bool

    var body: some View {
        NavigationLink(destination: SettingsPageView(navBarHidden: $navBarHidden)) {
            Text("Show View")
        }
    }
}
struct SettingsPageView: View {
    @Binding var navBarHidden: Bool

    var body: some View {
        VStack {
            Text("This is a view")
        }
        .navigationBarTitle("Settings", displayMode: .inline)
        .onAppear {
            self.navBarHidden = false
        }
        .onDisappear {
            self.navBarHidden = true
        }
    }
}