如何获取使用MPMusicPlayerController播放的正在播放的歌曲的剩余时间？

Question

我想在我的应用程序中显示播放歌曲的剩余时间，我的代码为：

NSTimeInterval currentTime= musicPlayer.currentPlaybackTime; 
NSNumber *duration = [musicPlayer.nowPlayingItem valueForProperty:MPMediaItemPropertyPlaybackDuration]; 
NSLog(@"Current Playback Time: %f",currentTime);

Answer 1

如果要重现“音乐”应用中显示的时间：

double nowPlayingItemDuration = [[[musicPlayer nowPlayingItem] valueForProperty:MPMediaItemPropertyPlaybackDuration]doubleValue];
double currentTime = (double) [musicPlayer currentPlaybackTime];
double remainingTime = nowPlayingItemDuration - currentTime;

NSString *timeElapsed;
NSString *timeRemaining;

if (nowPlayingItemDuration >= 3600.0) {
    timeElapsed = [NSString stringWithFormat: @"%02d:%02d:%02d",
                           (int)currentTime/3600,
                           (int) (currentTime/60)%60,
                           (int) currentTime%60];
    timeRemaining = [NSString stringWithFormat:@"- %02d:%02d:%02d",
                             (int)remainingTime/3600,
                             (int) (remainingTime/60)%60,
                             (int) remainingTime%60];

} else {
    timeElapsed = [NSString stringWithFormat: @"%02d:%02d",
                           (int) currentTime/60,
                           (int) currentTime%60];
    timeRemaining = [NSString stringWithFormat:@"- %02d:%02d",
                             (int) remainingTime/60,
                             (int) remainingTime%60];
}

Answer 2

• 如果要在进度视图中显示该代码，请遵循以下代码，它将为您提供帮助。

  MPMediaItem *temp; NSTimeInterval trackLength = [[temp valueForProperty:MPMediaItemPropertyPlaybackDuration] doubleValue]; song.songDuration = [temp valueForProperty:MPMediaItemPropertyPlaybackDuration]; 

NSTimer *timer= [NSTimer scheduledTimerWithTimeInterval:1
                                                target:self
                                              selector:@selector(updateProgress)
                                              userInfo:nil
                                               repeats:YES];

-(void) updateProgress{
itemDur++;
        WASong *song = [self.songObjects objectAtIndex:self.cellIndexPath.row];

        CGFloat progress =itemDur/[song.songDuration doubleValue];

}