ios - SwiftUI:检测 NavigationView 后退按钮按下

Question

在 SwiftUI当我在 DetailView1 内时，我找不到检测用户何时点击导航 View 的默认后退按钮的方法。在这段代码中:

struct RootView: View {
    @State private var showDetails: Bool = false
    var body: some View {
        NavigationView {
            VStack {
                NavigationLink(destination: DetailView1(), isActive: $showDetails) {
                    Text("show DetailView1")
                }
            }
            .navigationBarTitle("RootView")
        }
    }
}

struct DetailView1: View {
    @State private var showDetails: Bool = false
    var body: some View {
        NavigationLink(destination: DetailView2(), isActive: $showDetails) {
            Text("show DetailView2")
        }
        .navigationBarTitle("DetailView1")
    }
}

struct DetailView2: View {
    var body: some View {
        Text("")
            .navigationBarTitle("DetailView2")
    }
}

使用 .onDisappear不能解决问题，因为在弹出 View 或推送新 View 时会调用它的闭包。

Answer 1

快速的解决方案是创建一个自定义的后退按钮，因为现在框架没有这种可能性。

struct DetailView : View {

    @Environment(\.presentationMode) var mode: Binding<PresentationMode>

    var body : some View {
        Text("Detail View")
            .navigationBarBackButtonHidden(true)
            .navigationBarItems(leading: Button(action : {
                self.mode.wrappedValue.dismiss()
            }){
                Image(systemName: "arrow.left")
            })
    }
}