将视图方向锁定为仅横向

Question

我正在尝试使用以下代码从纵向视图呈现横向视图

   Button {
      isLandscapeViewPresented.toggle()
   } label: {
      Text("Click for landscape view")
   }.fullScreenCover(isPresented: $isLandscapeViewPresented) {
     LandscapeOnlyView {
        LandscapeView()
     }
   }

在 LandscapeOnlyView 包装器中我有如下

struct LandscapeOnlyView<Content: View>: UIViewControllerRepresentable {
    
    let content: Content
    
    init(@ViewBuilder content: () -> Content) {
        self.content = content()
    }
    
    func updateUIViewController(_ uiViewController: UIViewControllerType, context: Context) { }
    
    
    func makeUIViewController(context: Context) -> some UIViewController {
        return LandscapeHostingController(rootView: content)
    }
}

对于持有 rootview 的 LandscapeHostingController 如下：

class LandscapeHostingController<Content: View>: UIHostingController<Content> {
        
    override var supportedInterfaceOrientations: UIInterfaceOrientationMask {
        return .landscape
    }
        
    override func viewWillAppear(_ animated: Bool) {
        super.viewWillAppear(animated)
        AppDelegate.orientationLock = .landscape
        let scene = UIApplication.shared.connectedScenes.first as? UIWindowScene
        scene?.requestGeometryUpdate(.iOS(interfaceOrientations: .landscapeRight), errorHandler: { error in
            print(error)
        })
    }
        
    override func viewWillDisappear(_ animated: Bool) {
        super.viewWillDisappear(animated)
        
        AppDelegate.orientationLock = .portrait
        let scene = UIApplication.shared.connectedScenes.first as? UIWindowScene
        scene?.requestGeometryUpdate(.iOS(interfaceOrientations: .portrait), errorHandler: { error in
            print(error)
        })
    }
}

我正在使用 AppDelegate，正如您所看到的，我在哪里更新了orientationLock，只要我需要更改方向，supportedInterfaceOrientations 覆盖就会返回更新后的方向。

我得到以下输出。

我需要 LandscapeView 甚至在呈现之前就处于横向状态，这与上面显示的情况不同，其中视图切换到横向，因为方向更新是在 LandscapeHostingController 包装器的 viewWillAppear 中完成的，以实现快速 ui 视图。

我尝试过很多方法。我的方法有什么问题应该改变吗？

关于如何实现它有什么想法吗？

Answer 1

要将 SwiftUI 应用程序中视图的方向锁定为仅横向，您需要在

UIViewController

中或通过基于场景的更新来管理方向。下面是一种简化的方法，可确保视图在出现之前锁定在横向中。

代码示例：

1. 创建自定义 UIViewController 来管理横向方向：

import SwiftUI

struct LandscapeOnlyView<Content: View>: UIViewControllerRepresentable {
    let content: Content

    init(@ViewBuilder content: () -> Content) {
        self.content = content()
    }

    func makeUIViewController(context: Context) -> UIViewController {
        let controller = UIHostingController(rootView: content)
        controller.modalPresentationStyle = .fullScreen
        return LandscapeViewController(rootViewController: controller)
    }

    func updateUIViewController(_ uiViewController: UIViewController, context: Context) {}
}

class LandscapeViewController: UIViewController {
    override var supportedInterfaceOrientations: UIInterfaceOrientationMask {
        return .landscape
    }

    override func viewDidLoad() {
        super.viewDidLoad()
        let scene = UIApplication.shared.connectedScenes.first as? UIWindowScene
        scene?.requestGeometryUpdate(.iOS(interfaceOrientations: .landscapeRight), errorHandler: nil)
    }
}

2. 使用此视图作为特定于景观的内容的包装：

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

    var body: some View {
        Button("Open Landscape View") {
            isLandscapeViewPresented.toggle()
        }
        .fullScreenCover(isPresented: $isLandscapeViewPresented) {
            LandscapeOnlyView {
                Text("This view is locked in landscape orientation")
                    .padding()
                    .frame(maxWidth: .infinity, maxHeight: .infinity)
                    .background(Color.blue)
                    .foregroundColor(.white)
            }
        }
    }
}

这可确保

LandscapeView

在出现之前锁定横向方向，解决您所描述的问题。