ios - 从 Document 目录加载多个图像时 UICollectionView 卡住

Question

我正在加载超过 30-50 张图像，这些图像存储在文档目录中。它们所有的图像都立即加载到 collectionView 中，但是当滚动 collectionView 时它会卡住。

- (__kindof UICollectionViewCell *)collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath:(NSIndexPath *)indexPath
{
    static NSString *cellIdentifier = @"ImageCell";
    ImageCell *cell = [collectionView dequeueReusableCellWithReuseIdentifier:cellIdentifier forIndexPath:indexPath];

    //Load image from document  directory
    NSString *imageName = [arrCollection objectAtIndex:indexPath.row];
    NSString *imagePath = [NSString stringWithFormat:@"%@/%@",(AppObj).imagefolderPath, imageName];
    UIImage *localImg = [[UIImage alloc]initWithContentsOfFile:imagePath];

    cell.imgSketch.image = localImg;

    cell.txtName.text = [NSString stringWithFormat:@"%@",[imageName stringByReplacingOccurrencesOfString:@".png" withString:@""]];

    cell.layer.masksToBounds = YES;
    return cell;
}

我也试过下面的调度 block

dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_BACKGROUND, 0), ^{
                UIImage *localImg = [[UIImage alloc]initWithContentsOfFile:[NSString stringWithFormat:@"%@/%@",(AppObj).imagefolderPath,[arrCollection objectAtIndex:indexPath.row]]];
                dispatch_async(dispatch_get_main_queue(), ^{
                    cell.imgSketch.image = localImg;
                });
            });

请建议我解决这个问题的任何解决方案。

提前致谢

Answer 1

您可以使用 SDWebImage它还显示文档目录中的图像。

[cell.imgSketch sd_setImageWithURL:[NSURL fileURLWithPath:[NSString stringWithFormat:@"%@/%@",(AppObj).imagefolderPath,[arrCollection objectAtIndex:indexPath.row]]]];

注意:使用fileURLWithPath当您创建 NSURL 的对象时，因为它是文件的路径。