iphone - 如何将 KVO 添加到 MPMoviePlayer currentPlaybackTime？

Question

如何将 KVO 添加到 MPMoviePlayer 类的 currentPlaybackTime 属性？

Answer 1

您无法将 KVO 添加到 currentPlaybackTime，因为该属性未明确声明为 KVO 兼容。

相反，您可以尝试定期轮询玩家并存储位置，代码如下:

- (void) BeginPlayerPolling {
self.pollPlayerTimer = [NSTimer scheduledTimerWithTimeInterval:5
                                                       target:self 
                                                     selector:@selector(PollPlayerTimer_tick:)
                                                     userInfo:nil 
                                                      repeats:YES];  

}

- (void) PollPlayerTimer_tick:(NSObject *)sender {
// Store current playback position
if (player.playbackState == MPMoviePlaybackStatePlaying)
    lastRecordedPlaybackTime = player.currentPlaybackTime;
}

- (void) EndPlayerPolling {
if (pollPlayerTimer != nil)
{
    [pollPlayerTimer invalidate];
    self.pollPlayerTimer = nil;
}
}