How to make the Progressbar(UISlider) work dynamically in my app? [duplicate]

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UISlider to control AVAudioPlayer

I'm trying to develop a simple audio player app for iPhone,i need to implement the progress bar which has to run according to song(mediafile) length.How can i accomplish this?can i use slider with timer? Any help is appreciated in advance, Thank You.

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If you're playing your audio with AVPlayer then you can use its **addPeriodicTimeObserverForInterval**: method to update your UISlider. For example, if the name of your slider is playerScrubber:

    AVPlayerItem *newPlayerItem = [[AVPlayerItem alloc] initWithAsset:<your asset>];
    AVPlayer* player = [[AVPlayer alloc] initWithPlayerItem:newPlayerItem];

    CMTime interval = CMTimeMake(33, 1000);  // 30fps
    id playbackObserver = [player addPeriodicTimeObserverForInterval:interval queue:dispatch_get_current_queue() usingBlock: ^(CMTime time) {
            CMTime endTime = CMTimeConvertScale (player.currentItem.asset.duration, player.currentTime.timescale, kCMTimeRoundingMethod_RoundHalfAwayFromZero);
            if (CMTimeCompare(endTime, kCMTimeZero) != 0) {
                    double normalizedTime = (double) player.currentTime.value / (double) endTime.value;
                    playerScrubber.value = normalizedTime;
            }
        }];

And later when you're done:

[player removeTimeObserver:playbackObserver];

Goodluck!

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I'd say yes, a UISlider is your best friend. That's what iPod uses, too. You'll have to modify t a bit to indicate the progress visually. Make a timer that polls the position of your playback and updates the slider's value accordingly. You might make the slider's minimum value 0 and the maximum value the time of the playback in seconds.

Have a look at this post here on Stack Overflow, it has a pretty good demonstration: UISlider with ProgressView combined

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If you use AVAudioPlayer then it has a property called currentTime. You can assign its value to the UIProgressBar value like:

progressBar.value=myPlayer.currentTime;

You'll need to set up a timer to constantly update the progress.