如何创建音乐进度指示器/控件，例如 iPod 应用程序？

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5 年前已关闭。

Answer 1

到处省略了一些东西，但是插入就足够了。

// .h

IBOutlet UISlider *progressSlider;
NSTimer *progressTimer;

@property (nonatomic, retain) UISlider *progressSlider;
@property (nonatomic, retain) NSTimer *progressTimer;

- (void)updateSlider;
- (void)resetTimer:(NSTimer *)timer;


// .m

// synthesize variables

- (void)handleNowPlayingItemChanged:(id)notification {
    NSNumber *duration = [item valueForProperty:MPMediaItemPropertyPlaybackDuration];
    float totalTime = [duration floatValue];
    progressSlider.maximumValue = totalTime;
}

- (void)updateSlider {
    [progressSlider setValue:musicPlayer.currentPlaybackTime animated:YES];
}

- (void)resetTimer:(NSTimer *)timer {
    [progressTimer invalidate];
    progressTimer = nil;
    progressTimer = [NSTimer scheduledTimerWithTimeInterval:1 target:self
                                            selector:@selector(updateSlider)
                                            userInfo:nil repeats:YES];
}

// init and release methods (together at the bottom with view controls
//                                  (like viewDidLoad) for convenience)
//
// don't forget to register for notifications

@end

如果你想要一个示例应用程序（仅限设备；iPod 库），我可以写一个，但不会比这多多少。