你好我有一个下载图像的脚本,并在完成下载后动态设置UITableView高度,但有些图像随机显示,好奇的是,当我来回切换标签时,图像会突然出现。在options参数中,我传递了SDWebImageRetryFailed。
任何想法都会受到欢迎,谢谢。
@interface NeobuggyFrontPageViewController()
{
UIImageView *adBanner;
NSArray *news ;
NSMutableData *imageData;
NSURLConnection *connection;
UIImage *neoImage;
NSString *category;
RSSItem *item;
FrontPageViewNewsCell *cell ;
CGRect newFrame;
__block CGRect descFrame;
float newWidth , newHeight;
__block float blockHeight;
}
-(UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
item = [news objectAtIndex:[indexPath row]];
cell = [tableView dequeueReusableCellWithIdentifier:@"FrontPageNewsCell"];
[[cell newsTitle] setText:[item title]];
[[cell newsVideo] setAlpha:0.0];
if ([item newsImageURL]){
descFrame = [[cell newsBody] frame];
[[cell newsImage] setImageWithURL:[item newsImageURL] placeholderImage:[UIImage imageNamed:@"placeholderImage.png"] options:SDWebImageRetryFailed completed:^(UIImage *image, NSError *error, SDImageCacheType cacheType){
if (image) {
CGRect newsImageFrame = [[cell newsImage] frame];
float downImageWidth = image.size.width;
float downImageHeight = image.size.height;
float newsImageWidth = 304.00; //imageViewSize.size.width;
if (downImageWidth > newsImageWidth) {
float scaleFactor = newsImageWidth / downImageWidth;
newWidth = downImageWidth * scaleFactor;
newHeight = downImageHeight * scaleFactor;
} else {
newWidth = downImageWidth;
newHeight = downImageHeight;
}
newFrame = CGRectMake(newsImageFrame.origin.x, newsImageFrame.origin.y, newWidth, newHeight);
[[cell newsImage] setFrame:newFrame]; //asigno el nuevo frame a la imagen .
float newOriginY = newFrame.origin.y + newFrame.size.height + 10.00;
descFrame = CGRectMake(cell.newsBody.frame.origin.x,
newOriginY,
304.00,
cell.newsBody.frame.size.height);
blockHeight = newHeight;
}
NSLog(@"image %@ cached ? %u", image ,cacheType);
if (error) {
NSLog(@"Error: %@",error);
}
}];
} else if([item newsVideoURL]) {
[[cell newsImage] setAlpha:0.0];
[[cell newsVideo] setAlpha:1.0];
[[cell newsVideo] loadRequest:[NSURLRequest requestWithURL:[item newsVideoURL]]];
float newOriginY = cell.newsVideo.frame.origin.y + cell.newsVideo.frame.size.height + 10.00;
descFrame = CGRectMake(cell.newsBody.frame.origin.x, newOriginY, 304, cell.newsBody.frame.size.height);
blockHeight = cell.newsVideo.frame.size.height;
}
[[cell newsImage] setNeedsDisplay];
NSString *desc = [[NSString alloc] initWithString:[item description]];
[[cell newsBody] setFrame:descFrame];
desc = [desc htmlToString:desc];
[[cell newsBody] setText:desc];
[[cell newsBody] setNumberOfLines:0];
[[cell newsBody] sizeToFit];
[cell setSelectionStyle:UITableViewCellSelectionStyleNone];
return cell;
}
-(CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath {
cell = (FrontPageViewNewsCell *)[self tableView:tableView cellForRowAtIndexPath:indexPath];
CGSize descHeight = [[[cell newsBody] text] sizeWithFont:[[cell newsBody] font] constrainedToSize:cell.newsBody.frame.size lineBreakMode:[[cell newsBody] lineBreakMode]];
CGSize titleHeight = [[[cell newsTitle] text] sizeWithFont:[[cell newsTitle] font] constrainedToSize:cell.newsTitle.frame.size lineBreakMode:[[cell newsTitle] lineBreakMode]];
newHeight = cell.newsImage.frame.size.height;
if (blockHeight == 0) {
[tableView reloadData];
} else {
float ch = titleHeight.height + blockHeight + descHeight.height + 70;
[self setCellHeight:ch];
}
return _cellHeight;
}
部分解决了虽然解决方案不够理想。因为我只需要显示10个单元格,所以我阻止了UITableViewCell的重用
-(UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
item = [news objectAtIndex:[indexPath row]];
NSString *identifier = [NSString stringWithFormat:@"Cell %d", indexPath.row];
UINib *nib = [UINib nibWithNibName:@"FrontPageViewNewsCell" bundle:nil];
[[self tableView] registerNib:nib forCellReuseIdentifier:identifier];
cell = [tableView dequeueReusableCellWithIdentifier:identifier];
// cell = [tableView dequeueReusableCellWithIdentifier:@"FrontPageNewsCell"];
仍然有兴趣找到重用细胞的解决方案
谢谢,