MPMoviePlayerController UIGestureRecognizer在全屏时不会触发

Question

我有MPMoviePlayerController，它有一些UIGestureRecognizers。它在普通视图中运行良好，但是当玩家进入全屏时，即使事件被绑定，也不会触发事件。

以下是我绑定事件的方式：

UISwipeGestureRecognizer * nextChannelRecognizer = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:@selector(gotoNextChannel)];
    [nextChannelRecognizer setDirection:(UISwipeGestureRecognizerDirectionLeft)];
    [[player.view.subviews objectAtIndex:0] setUserInteractionEnabled:YES];
    [[player.view.subviews objectAtIndex:0] addGestureRecognizer:nextChannelRecognizer];

    UISwipeGestureRecognizer * previousChannelRecognizer = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:@selector(gotoPreviousChannel)];
    [previousChannelRecognizer setDirection:(UISwipeGestureRecognizerDirectionRight)];
    [[player.view.subviews objectAtIndex:0] addGestureRecognizer:previousChannelRecognizer];

    for (UIGestureRecognizer *g in ((UIView *)[player.view.subviews objectAtIndex:0]).gestureRecognizers) {
        NSLog(@"g %@", g.class);
    }

在普通视图和全屏视图中，循环中的代码输出这些

MPTapGestureRecognizer
MPSwipeGestureRecognizer
UIPinchGestureRecognizer
MPActivityGestureRecognizer
UITapGestureRecognizer
UITapGestureRecognizer
UIPinchGestureRecognizer
UISwipeGestureRecognizer
UISwipeGestureRecognizer

我尝试使用播放器视图的视图边界添加另一个临时视图，并将相同的事件绑定到它，但结果是相同的。

你能告诉我为什么它不起作用吗？怎么了？