iphone - 为什么 MPMovieLoadState 的状态为 5？

Question

我找到MPMoviePlayerController.h，有

enum {
    MPMovieLoadStateUnknown        = 0,
    MPMovieLoadStatePlayable       = 1 << 0,
    MPMovieLoadStatePlaythroughOK  = 1 << 1, // Playback will be automatically started in this state when shouldAutoplay is YES
    MPMovieLoadStateStalled        = 1 << 2, // Playback will be automatically paused in this state, if started
};
typedef NSInteger MPMovieLoadState;

但是当我这么做的时候

NSLog(@"%d",player.loadState)

它打印出 5 或有时 3，这是怎么发生的？据我所知，loadstate 的值为 0,1,2,4，请参阅开发人员文档。 谢谢!

Answer 1

playState 是一个位掩码。可以设置任意数量的位，例如

MPMovieLoadStatePlaythroughOK | MPMovieLoadStatePlayable

检查如下状态:

MPMovieLoadState state = [playerController loadState];
if( state & MPMovieLoadStatePlaythroughOK ) {
        NSLog(@"State is Playthrough OK");
}