Question

我尝试向视频播放器添加一个按钮，当视频从嵌入式Web浏览器内部变为全屏时，该按钮会添加到视图中。

我看到了这个：Detect when a webview video becomes fullscreen on ios8。但是，我认为在那一点上我们没有指向视频播放器的指针。也许有一种方法可以遍历窗口视图的所有子视图并抓取任何AVPlayer实例？

理想情况下，我可以这样做：

NSNotificationCenter.defaultCenter().addObserverForName(
    UIWindowDidResignKeyNotification,
    object: self.view.window,
    queue: nil
) { notification in
    let window = whatever the window is now
    let player = window.methodThatReturnsVideoPlayer
    // do stuff with player
    let button = UIButton(...)
    window.view.addSubView(button)
}

Answer 1

没有公共API方法可以在UIWebView中获取指向视频播放器的指针。

然而，有一种不安全的方式来访问视频播放器。使用反射，您可以遍历UIWebView的子视图并尝试找到播放器：

- (UIView *)getViewInsideView:(UIView *)view withPrefix:(NSString *)classNamePrefix {
    UIView *webBrowserView = nil;
    for (UIView *subview in view.subviews) {
        if ([NSStringFromClass([subview class]) hasPrefix:classNamePrefix]) {
            return subview;
        } else {
            if((webBrowserView = [self getViewInsideView:subview withPrefix:classNamePrefix])) {
                break;
            }
        }
    }
    return webBrowserView;
}

- (UIViewController *)movieControllerFromWebView:(UIWebView *)webview {
    UIViewController *movieController = nil;
    @try {
        UIView *movieView = [self getViewInsideView:webview withPrefix:[NSString stringWithFormat:@"MP%@oView", @"Vide"]];
        SEL mpavControllerSel = NSSelectorFromString([NSString stringWithFormat:@"mp%@roller", @"avCont"]);
        if ([movieView respondsToSelector:mpavControllerSel]) {
#pragma clang diagnostic push
#pragma clang diagnostic ignored "-Warc-performSelector-leaks"
            movieController = (UIViewController *)[movieView performSelector:mpavControllerSel];
#pragma clang diagnostic pop
        }
    }
    @catch (NSException *exception) {
        NSLog(@"Failed to get movieController: %@", exception);
    }

    return movieController;
}

此代码已从YouTubeHacks.m采用。

您的milage可能会有所不同，因为Apple倾向于使用不同的SDK（MPMoviePlayerController，UIMovieView，MPVideoView，UIMoviePlayerController等更改其播放器对象的名称。）。我会查看MediaPlayer.framework private headers以供参考。

在UIWebView中进入全屏时如何拦截视频？

1 个答案: