ios - 完全可见时在 UITableViewCell 上播放视频

Question

我有一个包含视频 URL 的数组，我想在 UITableviewcell 完全可见时播放这些视频。

我试过了

- (void)scrollViewDidScroll:(UIScrollView *)aScrollView 
{
    NSArray* cells = homeTabl.visibleCells;

    for (HomeCell* cell in cells) 
    {
        if (cell.frame.origin.y > offset.y &&
        cell.frame.origin.y + cell.frame.size.height < offset.y + bounds.size.height)
        {
            NSIndexPath *path = [homeTabl indexPathForCell:cell] ;
            index = path.row;
            fullvisible = YES;
            [homeTabl reloadData];
        }
        else
        {
            fullvisible = NO;
        }
    }
}

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
     if (fullvisible) 
     {
          NSURL *url = [NSURL URLWithString:[[responsearray objectAtIndex:indexPath.row]valueForKey:@"feed_video"]];

          cell.videoItem = [AVPlayerItem playerItemWithURL:url];
          cell.videoPlayer = [AVPlayer playerWithPlayerItem:cell.videoItem];
          cell.avLayer = [AVPlayerLayer playerLayerWithPlayer:cell.videoPlayer];
          cell.videoPlayer.actionAtItemEnd = AVPlayerActionAtItemEndNone;
          [cell.videoItem addObserver:self forKeyPath:@"playbackBufferEmpty" options:NSKeyValueObservingOptionNew context:nil];
          [cell.videoItem addObserver:self forKeyPath:@"playbackLikelyToKeepUp" options:NSKeyValueObservingOptionNew context:nil];

          [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(itemDidBufferPlaying:) name:AVPlayerItemPlaybackStalledNotification object:nil];
          [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(itemDidFinishPlaying:) name:AVPlayerItemDidPlayToEndTimeNotification object:nil];

          cell.avLayer.frame = CGRectMake(5, 9, 310, 310);
          [cell.contentView.layer addSublayer:cell.avLayer];
          [cell.videoPlayer play];
          [cell.contentView addSubview:cell.videoActivity];
     }
     else
     {
         cell.videoPlayer = nil;
         [cell.avLayer removeFromSuperlayer];
         cell.videoItem = nil;
         [cell.videoPlayer pause];
     }
}

这工作正常 - 但它可怕地减慢了表格 View 的滚动速度。请建议我一些其他更好的方法。

Answer 1

你可以使用

-(void)scrollViewDidEndDecelerating:(UIScrollView *)scrollView {
    isScrolling = NO;
    [homeTabl reloadData];
}

-(void)scrollViewWillBeginDragging:(UIScrollView *)aScrollView
{
    isScrolling = YES;
    [homeTabl reloadData];
    index = -1;
}

并在 cellForRowatindexpath 中

if (fullvisible && index == indexPath.row) {
        if (!isScrolling) {

            NSLog(@"video index---%d",indexPath.row);

            if (index == indexPath.row) {
                NSLog(@"video index---%d",indexPath.row);
                cell.videoActivity.hidden = NO;

                // if (index == indexPath.row) {
                NSURL *url = [NSURL URLWithString:[[responsearray objectAtIndex:indexPath.row]valueForKey:@"feed_video"]];

                dispatch_queue_t queue = dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_HIGH, 0ul);

                dispatch_async(queue, ^{
                    cell.videoItem = [AVPlayerItem playerItemWithURL:url];

                    dispatch_sync(dispatch_get_main_queue(), ^{
                        cell.videoPlayer = [AVPlayer playerWithPlayerItem:cell.videoItem];
                        cell.avLayer = [AVPlayerLayer playerLayerWithPlayer:cell.videoPlayer];
                        cell.videoPlayer.actionAtItemEnd = AVPlayerActionAtItemEndNone;
                        [cell.videoItem addObserver:self forKeyPath:@"playbackBufferEmpty" options:NSKeyValueObservingOptionNew context:nil];
                        [cell.videoItem addObserver:self forKeyPath:@"playbackLikelyToKeepUp" options:NSKeyValueObservingOptionNew context:nil];

                        [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(itemDidBufferPlaying:) name:AVPlayerItemPlaybackStalledNotification object:nil];
                        [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(itemDidFinishPlaying:) name:AVPlayerItemDidPlayToEndTimeNotification object:nil];

                        cell.avLayer.frame = CGRectMake(5, 9, 310, 310);
                        [cell.contentView.layer addSublayer:  cell.avLayer];
                        [ cell.videoPlayer play];
                        [cell.contentView addSubview:cell.videoActivity];
                    });
                });
                //                }
                //                else{
                //                    cell.videoActivity.hidden = YES;
                //                    cell.videoPlayer = nil;
                //                    [cell.avLayer removeFromSuperlayer];
                //                    cell.videoItem = nil;
                //                    [cell.videoPlayer pause];
                //                }
            }
        }}

    else{

        cell.videoActivity.hidden = YES;
        cell.videoPlayer = nil;
        [cell.avLayer removeFromSuperlayer];
        cell.videoItem = nil;
        [cell.videoPlayer pause];

    }