如何知道图像已在SDWebImage中下载

Question

Currently I am integrating SDWebImage in my project,

1) #import "UIButton+WebCache.h"

2) [button setImageWithURL:url placeholderImage:[UIImage imageNamed:@"no_photo.png"]];

Now I want to know when the image is downloaded successfully or not, How can I know this?

Answer 1

You can do this using the setImageWithURL: method and blocks like so:

Start your downloading animation. Then use this to download the image into an image view (or button, as you seem to be doing that above).

    [imageView setImageWithURL:[NSURL URLWithString:imageURL]
               placeholderImage:[UIImage imageNamed:@"YourPlaceholder.png"]
                        success:^(UIImage *image) {
                            // remove animation

                        }
                        failure:^(NSError *error) {
                            NSLog(@"thumbnail error: %@",error);
                            // handle failed download

                        }];

Answer 2

try this for latest version of SDWebImageManager

/**
* Check if image has already been cached
*/
- (BOOL)diskImageExistsForURL:(NSURL *)url;

Answer 3

在项目中搜索memcache setObject ，下载后此行将图像存储在缓存中。在此行之后，您可以发布通知并在您自己的类中检查它。