Question

我只想为IBOutlet设置图片并为其创建[_Image1 sd_setBackgroundImageWithURL:[NSURL URLWithString:[arrayGallery valueForKey:@"link"][0]] forState:UIControlStateNormal placeholderImage:[UIImage imageNamed:@"blurred-background"] completed:^(UIImage *image, NSError *error, SDImageCacheType cacheType, NSURL *imageURL) { [_ImageLoader1 stopAnimating]; [_ImageLoader1 removeFromSuperview]; }];。我上面有一个加载器，当加载图像时，加载器将停止并为该按钮分配新图像。调用代码时，占位符图像将保留，并且不会加载URL图像

#define LOCKED 0
#define UNLOCKED 1
#define PRINT(x) (x == LOCKED) ? printf("locked") : printf("unlocked")

Answer 1

您正在使用完成块从网址下载图片。所以你需要按照以下方式去做。

 [_Image1 sd_setBackgroundImageWithURL:[NSURL URLWithString:[arrayGallery valueForKey:@"link"][0]] forState:UIControlStateNormal placeholderImage:[UIImage imageNamed:@"blurred-background"] completed:^(UIImage *image, NSError *error, SDImageCacheType cacheType, NSURL *imageURL) {

            [_Image1 setImage:btnImage forState:UIControlStateNormal];//Don't forgot to check for error if error is nil or image is not nil then only set image

            [_ImageLoader1 stopAnimating];
            [_ImageLoader1 removeFromSuperview];
  }];

Answer 2

如果您正在使用SDWebImageCache的完成块，请在完成块内设置图像

[_Image1 sd_setBackgroundImageWithURL:[NSURL URLWithString:[arrayGallery valueForKey:@"link"][0]] forState:UIControlStateNormal placeholderImage:[UIImage imageNamed:@"blurred-background"] completed:^(UIImage *image, NSError *error, SDImageCacheType cacheType, NSURL *imageURL) {
        _Image1.image = image;
        [_ImageLoader1 stopAnimating];
        [_ImageLoader1 removeFromSuperview];
    }];

Answer 3

在主线程中更新图像尝试这样的事情

 [_Image1 sd_setBackgroundImageWithURL:[NSURL URLWithString:[arrayGallery valueForKey:@"link"][0]] forState:UIControlStateNormal placeholderImage:[UIImage imageNamed:@"blurred-background"] completed:^(UIImage *image, NSError *error, SDImageCacheType cacheType, NSURL *imageURL) {
        [_ImageLoader1 stopAnimating];
        [_ImageLoader1 removeFromSuperview];

        dispatch_sync(dispatch_get_main_queue(), ^{
           _Image1.image = image;   
        });

 }];

Answer 4

从NSData和NSUrlRequest＆＃34;您的网址＆＃34;获取NSUrl URLWithString

并将NSData转换为UIImage并设置背景图片。

Answer 5

首先获取图片网址并检查图片网址长度是否大于零/ null。并确保图像网址正常工作。点击url上的Browser，然后检查您是否获得了正确的图像。

SDWebImage库正在更新按钮图片，但Main Thread上没有发生这种情况。这可能是未更新backgroundImage的{{1}}的原因。

UIButton

停止- (void)sd_setBackgroundImageWithURL:(nullable NSURL *)url forState:(UIControlState)state placeholderImage:(nullable UIImage *)placeholder options:(SDWebImageOptions)options completed:(nullable SDExternalCompletionBlock)completedBlock { if (!url) { [self.imageURLStorage removeObjectForKey:@(state)]; return; } NSString *imageURL = [arrayGallery valueForKey:@"link"][0]; self.imageURLStorage[@(state)] = url; __weak typeof(self)weakSelf = self; [self sd_internalSetImageWithURL:url placeholderImage:placeholder options:options operationKey:[NSString stringWithFormat:@"UIButtonBackgroundImageOperation%@", @(state)] setImageBlock:^(UIImage *image, NSData *imageData) { [weakSelf setBackgroundImage:image forState:state]; } progress:nil completed:completedBlock]; }动画并在loader上设置UIButton背景图片。

main thread

图像未加载图像

5 个答案: