IOS uses SDwebImage to cache images and display them when the network is disconnected,
[_ LoadImageViewsetShowActivityIndicatorView: YES];
[_ LoadImageViewsetIndicatorStyle: UIActivityIndicatorViewStyleGray];
_ LoadImageView. contentMode = UIViewContentModeScaleAspectFill;
[_ LoadImageViewsd_setImageWithURL: self. imageUrlplaceholderImage: nil];
// Cache the image
SDWebImageManager * manager = [SDWebImageManagersharedManager];
Manager. delegate = self;
[Manager. imageDownloaderdownloadImageWithURL: self. imageUrloptions: SDWebImageDownloaderContinueInBackgroundprogress: ^ (NSInteger receivedSize, NSInteger expectedSize ){
} Completed: ^ (UIImage * image, NSData * data, NSError * error, BOOL finished ){
NSLog (@ "--- save image is % @", image );
[Manager. imageCachestoreImage: image forKey: @ "one" toDisk: YES] ;}]; // retrieves and displays the image from the cache.
SDWebImageManager * manager = [[SDWebImageManageralloc] init]; UIImage * image = [manager. imageCacheimageFromMemoryCacheForKey: @ "one"];