我有一個圖像滑塊,並使用setImageWithURLRequest從url下載圖像。假設用戶從應用程序代碼的左側滑動到右側,那麼我必須顯示我可以實現的最右側的索引圖像,但在此之後,我必須從索引的開頭下載圖像。如何實現這一目標?AFNetworking:使用setImageWithURLRequest的異步圖像下載
for (int i = 0; i < self.items.count; i++) {
CGRect frame;
frame.origin.x = scrollView.frame.size.width * i;
frame.origin.y = 0;
frame.size = scrollView.frame.size;
UIView *subview = self.view;
UIImageView *imageView = [[UIImageView alloc] initWithFrame:frame];
imageView.contentMode = UIViewContentModeCenter;
subview = imageView;
NSURLRequest *imagerequest = [NSURLRequest requestWithURL:[_items objectAtIndex:i]];
__weak UIImageView *weakImageView = (UIImageView *) subview;
[(UIImageView *) subview setImageWithURLRequest:imagerequest
placeholderImage:[UIImage imageNamed:@"placeholder.gif"]
success:^(NSURLRequest *request, NSHTTPURLResponse *response, UIImage *image) {
UIImageView *strongImageView = weakImageView; // make local strong reference to protect against race conditions
if (!strongImageView) return;
strongImageView.image = image;
}
failure:^(NSURLRequest *request, NSHTTPURLResponse *response, NSError *error) {
//[activityIndicatorView removeFromSuperview];
// do any other error handling you want here
}];
[scrollView addSubview:subview];
}
請添加一些您的代碼 – gran33