我正在水平集合视图中显示从服务器接收到的动态图片。当我设置集合视图时,我设置了以下内容:
-(void)setupCollectionView{
[self setupPageControlView];
self.screensCollectionView.delegate=self;
self.screensCollectionView.dataSource=self;
[self.screensCollectionView registerNib:[UINib nibWithNibName:@"FGAppScreensCollectionViewItemCell" bundle:nil] forCellWithReuseIdentifier:@"screenCell"];
UICollectionViewFlowLayout *flowLayout = [[UICollectionViewFlowLayout alloc] init];
[flowLayout setScrollDirection:UICollectionViewScrollDirectionHorizontal];
[flowLayout setMinimumInteritemSpacing:0.0f];
[flowLayout setMinimumLineSpacing:0.0f];
[flowLayout setItemSize:CGSizeMake(165, 255)];
//[self.screensCollectionView setPagingEnabled:YES];
[self.screensCollectionView setCollectionViewLayout:flowLayout];
在cellForRowAtIndexPath方法中,我会这样下载图片:
-(UICollectionViewCell *)collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath:(NSIndexPath *)indexPath{
static NSString *cellIdentifier = @"screenCell";
FGAppScreensCollectionViewItemCell *cell = [collectionView dequeueReusableCellWithReuseIdentifier:cellIdentifier forIndexPath:indexPath];
NSURLRequest *urlRequest = [NSURLRequest requestWithURL:[NSURL URLWithString:[self.imageURLArray objectAtIndex:indexPath.row]]];
UIActivityIndicatorView *spinner = [[UIActivityIndicatorView alloc] initWithActivityIndicatorStyle:UIActivityIndicatorViewStyleGray];
[spinner startAnimating];
[spinner setFrame:CGRectMake(50, 100, 20, 20)];
[cell.contentView addSubview:spinner];
[cell.screenImageView setImageWithURLRequest:urlRequest placeholderImage:nil success:^(NSURLRequest *request, NSHTTPURLResponse *response, UIImage *image) {
//STOP THE SPINNER
for (UIView* view in [cell.contentView subviews]) {
if ([view isKindOfClass:[UIActivityIndicatorView class]]) {
[view removeFromSuperview];
}
}
cell.screenImageView.image = image;
} failure:^(NSURLRequest *request, NSHTTPURLResponse *response, NSError *error) {
//
}];
[cell.screenImageView setImageWithURL:[NSURL URLWithString:[self.imageURLArray objectAtIndex:indexPath.row]]];
if (self.delegate) {
UITapGestureRecognizer* g = [[UITapGestureRecognizer alloc] initWithTarget:self.delegate action:@selector(showPopUpImageView:)];
[cell.screenImageView addGestureRecognizer:g];
}
return cell;
然而,在集合视图中显示了竖屏和横屏图片。竖屏图像显示正常,但横屏图像在集合视图中显示过小。我需要做的是根据图像大小调整单元格的大小,以使它们填充正确的纵横比。
我添加了以下类似的方法,但问题是它会在一开始就调用所有单元格,一旦我在cellForRowAtIndexPath方法中下载了图像,它就不会再被调用:
- (CGSize)collectionView:(UICollectionView *)collectionView
layout:(UICollectionViewLayout*)collectionViewLayout sizeForItemAtIndexPath:(NSIndexPath *)indexPath
{
return CGSizeMake(165, 255);
因此,我想知道如何实现这个功能,请让我知道是否需要更多信息?