检测 webview 视频何时在 ios8 上变为全屏

Question

我有一个应用程序，用户可以在其中打开 UIWebview 的视频，包括 Youtube 视频。 在 iOS7 中，我能够在开始播放或全屏播放时收到通知，这对我向用户显示某些选项和修改界面至关重要。

我以前用这个：

[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(VideoExitFullScreen:) name:@"UIMoviePlayerControllerDidExitFullscreenNotification" object:nil];

[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(VideoEnterFullScreen:) name:@"UIMoviePlayerControllerDidEnterFullscreenNotification" object:nil];

但是，从 iOS8 开始，我无法做到这一点。就像 UIWebview 视频不再触发通知一样。但是，正如我测试过的，它仍然是由普通视频、非 Webview 触发的。

知道发生了什么变化吗？

Answer 1

这是我为此找到的解决方法..

[[NSNotificationCenter defaultCenter] addObserver:self
                                             selector:@selector(VideoExitFullScreen:)
                                                 name:UIWindowDidBecomeVisibleNotification
                                               object:self.view.window];

[[NSNotificationCenter defaultCenter] addObserver:self
                                             selector:@selector(VideoEnterFullScreen:)
                                                 name:UIWindowDidBecomeHiddenNotification
                                               object:self.view.window];

Answer 2

斯威夫特 5.1：

NotificationCenter.default.addObserver(
    forName: UIWindow.didResignKeyNotification,
    object: self.view.window,
    queue: nil
) { notification in
    print("Video is now fullscreen")
}

NotificationCenter.default.addObserver(
    forName: UIWindow.didBecomeKeyNotification,
    object: self.view.window,
    queue: nil
) { notification in
    print("Video stopped")
}

Answer 3

Swift 4.2、iOS 12.1 和 WKWebView 的更新：

override func viewWillAppear(_ animated: Bool) {
    super.viewWillAppear(animated)

    // listen for videos playing in fullscreen
    NotificationCenter.default.addObserver(self, selector: #selector(onDidEnterFullscreen(_:)), name: UIWindow.didBecomeVisibleNotification, object: view.window)

    // listen for videos stopping to play in fullscreen
    NotificationCenter.default.addObserver(self, selector: #selector(onDidLeaveFullscreen(_:)), name: UIWindow.didBecomeHiddenNotification, object: view.window)
}

override func viewWillDisappear(_ animated: Bool) {
    super.viewWillDisappear(animated)

    // remove video listeners
    NotificationCenter.default.removeObserver(self, name: UIWindow.didBecomeVisibleNotification, object: view.window)
    NotificationCenter.default.removeObserver(self, name: UIWindow.didBecomeHiddenNotification, object: view.window)
}

@objc func onDidEnterFullscreen(_ notification: Notification) {
    print("video is now playing in fullscreen")
}

@objc func onDidLeaveFullscreen(_ notification: Notification) {
    print("video has stopped playing in fullscreen")
}

Answer 4

@NorthBlast 的答案非常适合检测出现在包含UIWebView 的UIViewController 顶部的任何UIWindow。不幸的是，很难过滤出UIWindow 是什么类型的（因为，嗯......你无法真正知道它是视频还是其他类型的窗口）。

我更喜欢过滤 3 种特殊情况，您确定它们是不是视频播放器窗口，它们是：

1) _UIAlertControllerShimPresenterWindow，这是一种在使用警报时出现的窗口（如UIAlertView）。

2) UITextEffectsWindow，在呈现特殊的 iOS 窗口时出现（如共享窗口，UIActivityViewController）。

3) UIRemoteKeyboardWindow 在展示键盘时出现（由于某种原因，这个类只在我使用 Swift 时出现，但在 Objective-C 上却没有......不知道为什么会这样）。

所以要订阅通知，我使用（就像@NorthBlast 所说）：

[[NSNotificationCenter defaultCenter] addObserver:self
                                         selector:@selector(windowDidBecomeActive:)
                                             name:UIWindowDidBecomeVisibleNotification
                                           object:nil];

[[NSNotificationCenter defaultCenter] addObserver:self
                                         selector:@selector(windowDidBecomeHidden:)
                                             name:UIWindowDidBecomeHiddenNotification
                                           object:nil];

然后是实现：

- (void)windowDidBecomeActive:(NSNotification *)notification {
    if ( [self isVideoPlayerWindow:notification.object] ) {
        // Do what's needed if it is a video
        // For example, on a live streaming radio app, I would stop the audio if a video is started
    }
}

- (void)windowDidBecomeHidden:(NSNotification *)notification {
    if ( [self isVideoPlayerWindow:notification.object] ) {
        // Do what's needed if it is a video
    }
}

- (BOOL)isVideoPlayerWindow:(id)notificationObject {
    /*
     Define non video classes here, add more if you need it
    */
    static NSArray *nonVideoClasses = @[
        @"_UIAlertControllerShimPresenterWindow",
        @"UITextEffectsWindow",
        @"UIRemoteKeyboardWindow"
    ];

    BOOL isVideo = YES;
    for ( NSString *testClass in nonVideoClasses ) {
        isVideo = isVideo && ! [notificationObject isKindOfClass:NSClassFromString(testClass)];
    }

    return isVideo;
}

Answer 5

对于快速：

NotificationCenter.default.addObserver(self, selector: #selector(xxx), name: NSNotification.Name.MPMoviePlayerDidExitFullscreen, object: nil)