SwiftUI：再次轻按选定的选项卡时，弹出到根视图

Posted 2023-01-30

起点是TabView中的NavigationView。我正在努力寻找一个SwiftUI解决方案，以便在再次轻按所选标签时弹出导航堆栈内的根视图。在之前的SwiftUI时代，这很简单，如下所示：

func tabBarController(_ tabBarController: UITabBarController, didSelect viewController: UIViewController) 
    let navController = viewController as! UINavigationController
    navController.popViewController(animated: true)

您知道在SwiftUI中如何实现相同的目的吗？

当前，我使用依赖于UIKit的以下解决方法：

if let windowScene = scene as? UIWindowScene 
            let window = UIWindow(windowScene: windowScene)

            let navigationController = UINavigationController(rootViewController: UIHostingController(rootView:
                MyCustomView() // -> this is a normal SwiftUI file
                    .environment(\.managedObjectContext, context)
            ))
            navigationController.tabBarItem = UITabBarItem(title: "My View 1", image: nil, selectedImage: nil)

            // add more controllers that are part of tab bar controller

            let tabBarController = UITabBarController()
            tabBarController.viewControllers = [navigationController /*,  additional controllers */]

            window.rootViewController = tabBarController // UIHostingController(rootView: contentView)
            self.window = window
            window.makeKeyAndVisible()
        

答案

经过测试并与Xcode 11.2 / ios 13.2配合使用

完整模块代码：

import SwiftUI struct TestPopToRootInTab: View @State private var selection = 0 @State private var resetNavigationID = UUID() var body: some View let selectable = Binding( // << proxy binding to catch tab tap get: self.selection , set: self.selection = $0 // set new ID to recreate NavigationView, so put it // in root state, same as is on change tab and back self.resetNavigationID = UUID() ) return TabView(selection: selectable) self.tab1() .tabItem Image(systemName: "1.circle") .tag(0) self.tab2() .tabItem Image(systemName: "2.circle") .tag(1) private func tab1() -> some View NavigationView NavigationLink(destination: TabChildView()) Text("Tab1 - Initial") .id(self.resetNavigationID) // << making id modifiable private func tab2() -> some View Text("Tab2") struct TabChildView: View var number = 1 var body: some View NavigationLink("Child \(number)", destination: TabChildView(number: number + 1)) struct TestPopToRootInTab_Previews: PreviewProvider static var previews: some View TestPopToRootInTab()