NghiaTranUIT

        __weak FePreviewVideoViewController *weakSelf = self;
        timeObserver = [_player addPeriodicTimeObserverForInterval:CMTimeMake(15, 1) queue:dispatch_get_main_queue() usingBlock:^(CMTime time)
                       {
                           typeof(self) strongSelf = weakSelf;
                           
                           CGFloat currentTime = CMTimeGetSeconds(time);
                           
                           if (currentTime >= 15)
                           {
                                [strongSelf.player pause];

NghiaTranUIT

- (void) mergeAVAssetByArrAsset:(NSArray *) arrAsset
{
    AVMutableComposition * composition = [AVMutableComposition composition];
    
    for (AVAsset *asset in arrAsset)
    {
        CMTimeRange timeRange = CMTimeRangeMake(kCMTimeZero, asset.duration);
        
        [composition insertTimeRange:timeRange ofAsset:asset atTime:composition.duration error:nil];
    }

NghiaTranUIT

NSString *customURL = @"facebook://";
 
  if ([[UIApplication sharedApplication] 
    canOpenURL:[NSURL URLWithString:customURL]])
    {
      // App fb có cài
      return YES;
    }
    else
    {