AVPlayer seekToTime: backward not working

Question

I have the following code:

AVPlayerItem *currentItem = [AVPlayerItem playerItemWithURL:soundURL];
[self.audioPlayer replaceCurrentItemWithPlayerItem:currentItem];
[self.audioPlayer play];

where soundURL is a remoteURL. It works fine. The AVPlayer plays the music perfectly. I have a progress bar and i am updating it based on the current time of the player.

Everything works fine. My issue is when i drag the progress bar forward the audioplayer starts from the new location but if i drag the progressbar it doesn't start from the new location in fact it resumes from the previous location. Here is my progress bar drag start and stop code:

- (IBAction)progressBarDraggingStart:(id)sender
{
     if (self.audioPlayer.rate != 0.0)
     {
          [self.audioPlayer pause];
     }
}

- (IBAction)progressBarDraggindStop:(id)sender
{
     CMTime newTime = CMTimeMakeWithSeconds(self.progressBar.value, 1);
     [self.audioPlayer seekToTime:newTime];
     [self.audioPlayer play];
}

Can anyone help me fix this issue?

Answer 1

I suggest doing a couple of things. First, get the timescale value and pass it to the CMTime struct. Second, use the seekToTime:toleranceBefore:toleranceAfter:completionHandler: method for more accurate seeking. For example, your code would look like:

- (IBAction)progressBarDraggindStop:(id)sender {
    int32_t timeScale = self.audioPlayer.currentItem.asset.duration.timescale;

    [self.audioPlayer seekToTime: CMTimeMakeWithSeconds(self.progressBar.value, timeScale)
                 toleranceBefore: kCMTimeZero
                  toleranceAfter: kCMTimeZero
               completionHandler: ^(BOOL finished) {
                   [self.audioPlayer play];
               }];
}

Answer 2

I am using below code for dragging- Added completionHandler after @Corey's answer and it works great without any web-service dependency:

- (void) sliderValueChanged:(id)sender {
    if ([sender isKindOfClass:[UISlider class]]) {
        UISlider *slider = sender;

        CMTime playerDuration = self.avPlayer.currentItem.duration;
        if (CMTIME_IS_INVALID(playerDuration)) {
            return;
        }

        double duration = CMTimeGetSeconds(playerDuration);
        if (isfinite(duration)) {
            float minValue = [slider minimumValue];
            float maxValue = [slider maximumValue];
            float value = [slider value];

            double time = duration * (value - minValue) / (maxValue - minValue);

            [self.avPlayer seekToTime:CMTimeMakeWithSeconds(time, NSEC_PER_SEC) toleranceBefore:kCMTimeZero toleranceAfter:kCMTimeZero completionHandler:^(BOOL finished) {
                [self.avPlayer play];
            }];
        }
    }
}