话不多说，直接改UIImageView+WebCache.m 的这个方法
- (void)sd_setImageWithURL:(nullable NSURL *)url
placeholderImage:(nullable UIImage *)placeholder
options:(SDWebImageOptions)options
progress:(nullable SDWebImageDownloaderProgressBlock)progressBlock
completed:(nullable SDExternalCompletionBlock)completedBlock {
// [self sd_internalSetImageWithURL:url
// placeholderImage:placeholder
// options:options
// operationKey:nil
// setImageBlock:nil
// progress:progressBlock
// completed:completedBlock];
///图片加载的淡入淡出效果
[self sd_cancelCurrentImageLoad];
objc_setAssociatedObject(self, &imageURLKey, url, OBJC_ASSOCIATION_RETAIN_NONATOMIC);
if (!(options & SDWebImageDelayPlaceholder)) {
dispatch_main_async_safe(^{
self.image = placeholder;
});
}
if (url) {
// check if activityView is enabled or not
if ([self sd_showActivityIndicatorView]) {
[self sd_addActivityIndicator];
}
__weak __typeof(self)wself = self;
id <SDWebImageOperation> operation = [SDWebImageManager.sharedManager loadImageWithURL:url options:options progress:progressBlock completed:^(UIImage *image, NSData *data, NSError *error, SDImageCacheType cacheType, BOOL finished, NSURL *imageURL) {
[wself sd_removeActivityIndicator];
if (!wself) return;
dispatch_main_async_safe(^{
if (!wself) return;
if (image && (options & SDWebImageAvoidAutoSetImage) && completedBlock)
{
completedBlock(image, error, cacheType, url);
return;
}
else if (image) {
CATransition *animation = [CATransition animation];
animation.duration = .85f;
animation.type = kCATransitionFade;
animation.removedOnCompletion = YES;
[wself.layer addAnimation:animation forKey:@"transition"];
wself.image = image;
[wself setNeedsLayout];
} else {
if ((options & SDWebImageDelayPlaceholder)) {
wself.image = placeholder;
[wself setNeedsLayout];
}
}
if (completedBlock && finished) {
completedBlock(image, error, cacheType, url);
}
});
}];
[self.layer removeAnimationForKey:@"transition"];
[self sd_setImageLoadOperation:operation forKey:@"UIImageViewImageLoad"];
} else {
dispatch_main_async_safe(^{
[self sd_removeActivityIndicator];
if (completedBlock) {
NSError *error = [NSError errorWithDomain:SDWebImageErrorDomain code:-1 userInfo:@{NSLocalizedDescriptionKey : @"Trying to load a nil url"}];
completedBlock(nil, error, SDImageCacheTypeNone, url);
}
});
}
}