ios - 创建 AVPlayerLayer 会导致模拟器崩溃

Question

我有一个类在回调中返回 AVPlayer 和 AVSynchronisedLayer。当我使用 AVPlayer 初始化 AVPlayerLayer 时，我崩溃了(只发生在模拟器中)。代码如下所示:

  self.projectPlayer = [[MYMobilePlayer alloc] init];
  [self.projectPlayer setDelegate:self]; 
  [self.projectPlayer returnPlayerForProjectScene:self.projectScene andCallback:^(NSError *error, AVPlayer *player, AVSynchronizedLayer *syncLayer) {


      self.syncLayer = syncLayer;
      AVPlayerLayer *playerLayer = [AVPlayerLayer playerLayerWithPlayer:player];
      NSLog(@"%@",playerLayer); // Also crashes if I assign to private member variable
      // More code that uses the playerLayer - not needed to illustrate the problem

  }];

回调中返回的对象是正确的，所以我认为我不需要显示创建和返回它们的代码。

堆栈跟踪如下所示(不是很有帮助)。

知道这里会发生什么吗？

Answer 1

UIKit 代码应始终在主线程上调用。您的 returnPlayerForProjectScene 回调发生在其他视频处理线程上。将有问题的代码分派(dispatch)到主队列应该可以解决您的崩溃问题:

[self.projectPlayer returnPlayerForProjectScene:self.projectScene andCallback:^(NSError *error, AVPlayer *player, AVSynchronizedLayer *syncLayer) {

    dispatch_async(dispatch_get_main_queue(), ^{

        self.syncLayer = syncLayer;
        AVPlayerLayer *playerLayer = [AVPlayerLayer playerLayerWithPlayer:player];
        NSLog(@"%@",playerLayer); // Also crashes if I assign to private member variable
        // More code that uses the playerLayer - not needed to illustrate the problem

    });
}];