SwiftUI中AVPlayer旋转至竖屏时exitFullScreen未调用问题

使用SwiftUI搭配AVPlayer开发播放功能时，设备旋转至横屏可正常触发播放器进入全屏，旋转回竖屏时exitFullScreen函数未执行，播放器无法自动退出全屏。

• 进入全屏后，AVPlayerViewController会被系统以present方式弹出到独立的全屏展示容器，原有SwiftUI视图树中挂载的onReceive旋转监听会因为视图层级变化失效，竖屏旋转事件无法触发fullScreen状态更新。
• 原实现未做全屏状态幂等校验，updateUIViewController每次触发都会无条件调用全屏切换方法，重复调用私有进入全屏API会导致系统忽略后续的退出全屏指令。
• 旋转监听注册在SwiftUI包装视图层，和实际负责全屏展示的AVPlayerViewController实例生命周期不同步，状态变更无法传递到已经弹出的播放器控制器。

调整AVPlayer封装代码 #

新增Coordinator协调器统一处理旋转监听、状态同步，增加调用前置校验避免重复触发API：

import SwiftUI
import AVKit

struct AVPlayerControllerRepresentable: UIViewControllerRepresentable {
    @Binding var showFullScreen: Bool
    @Binding var player: AVPlayer
    
    func makeCoordinator() -> Coordinator {
        Coordinator(self)
    }
    
    func makeUIViewController(context: Context) -> AVPlayerViewController {
        let controller = AVPlayerViewController()
        controller.player = player
        controller.showsPlaybackControls = false
        // 将旋转监听注册在协调器上，生命周期和控制器绑定
        NotificationCenter.default.addObserver(
            context.coordinator,
            selector: #selector(Coordinator.handleOrientationChange),
            name: UIDevice.orientationDidChangeNotification,
            object: nil
        )
        context.coordinator.targetController = controller
        return controller
    }
    
    func updateUIViewController(_ uiViewController: AVPlayerViewController, context: Context) {
        // 仅在状态不匹配时触发全屏切换，避免重复调用
        guard context.coordinator.currentIsFullScreen != showFullScreen else { return }
        showFullScreen ? uiViewController.enterFullScreen(animated: true) : uiViewController.exitFullScreen(animated: true)
        context.coordinator.currentIsFullScreen = showFullScreen
    }
    
    class Coordinator: NSObject {
        let parent: AVPlayerControllerRepresentable
        weak var targetController: AVPlayerViewController?
        var currentIsFullScreen: Bool = false
        
        init(_ parent: AVPlayerControllerRepresentable) {
            self.parent = parent
        }
        
        @objc func handleOrientationChange() {
            DispatchQueue.main.async { [weak self] in
                guard let self = self, let controller = self.targetController else { return }
                let isLandscape = UIDevice.current.orientation.isLandscape
                guard self.currentIsFullScreen != isLandscape else { return }
                
                if isLandscape {
                    controller.enterFullScreen(animated: true)
                } else {
                    controller.exitFullScreen(animated: true)
                }
                self.currentIsFullScreen = isLandscape
                self.parent.showFullScreen = isLandscape
            }
        }
    }
}

extension AVPlayerViewController {
    func enterFullScreen(animated: Bool) {
        // 前置校验：当前控制器未处于present流程、未展示其他页面时才执行
        guard !isBeingPresented, presentedViewController == nil else { return }
        let selector = NSSelectorFromString("enterFullScreenAnimated:completionHandler:")
        guard responds(to: selector) else { return }
        perform(selector, with: animated, with: nil)
    }
    
    func exitFullScreen(animated: Bool) {
        let selector = NSSelectorFromString("exitFullScreenAnimated:completionHandler:")
        guard responds(to: selector) else { return }
        perform(selector, with: animated, with: nil)
    }
}

简化业务视图代码 #

移除原视图层挂载的旋转监听逻辑，避免重复触发状态变更：

VStack {
    AVPlayerControllerRepresentable(showFullScreen: $fullScreen, player: $player)
        .ignoresSafeArea()
        .frame(width: 290, height: 220)
        .overlay {
            BoxTv()
        }
        .opacity(1.0)
        .padding([.bottom, .top], 40)
}
.onAppear {
    player.play()
}

• 协调器和AVPlayerViewController生命周期绑定，旋转监听不会因为播放器弹出全屏而失效，竖屏旋转事件可以被正常捕获。
• 增加currentIsFullScreen状态标记，所有全屏切换操作前先做状态比对，从根源避免重复调用私有API导致的系统指令忽略问题。
• 给私有API调用增加方法响应校验、控制器展示状态校验，避免无效调用触发系统异常。
• 控制器层触发全屏切换后主动回写SwiftUI绑定状态，保证业务层状态和播放器实际展示状态完全同步。

内容的提问来源于stack exchange，提问作者faserx