我觉得sdwebimage的目的是给我们加载图片而已，像这种分辨率大不大的问题，人家哪里管的了那么多。最近项目中碰到一个坑，首页的图片大小居然有3300*3200,这么大的图显示完后，内存直接爆涨30M,当前就猜到问题所在。因为考虑到尽量不用动sdwebimage里面的深层代码，所以决定在最终显示的地方处理。
反正是因为最终显示的地方才导致内存爆涨，只有将图片进行裁剪就好了，
@interface UIView (WebCache),最终找到了这个类，最好是button和imageview一起处理一下
- (void)sd_setImage:(UIImage *)image imageData:(NSData *)imageData basedOnClassOrViaCustomSetImageBlock:(SDSetImageBlock)setImageBlock transition:(SDWebImageTransition *)transition cacheType:(SDImageCacheType)cacheType imageURL:(NSURL *)imageURL {
UIView *view = self;
SDSetImageBlock finalSetImageBlock;
if (setImageBlock) {
finalSetImageBlock = setImageBlock;
}
#if SD_UIKIT || SD_MAC
else if ([view isKindOfClass:[UIImageView class]]) {
UIImageView *imageView = (UIImageView *)view;
finalSetImageBlock = ^(UIImage *setImage, NSData *setImageData) {
//判断一下，如果图片分辨率很大，则进行裁剪
UIImage *resultImage = [self compressResolvingImage:setImage];
imageView.image = resultImage;
};
}
#endif
#if SD_UIKIT
else if ([view isKindOfClass:[UIButton class]]) {
UIButton *button = (UIButton *)view;
finalSetImageBlock = ^(UIImage *setImage, NSData *setImageData){
[button setImage:setImage forState:UIControlStateNormal];
};
}
#endif
再下面代码进行裁剪
/**处理分辨率大的问题*/
- (UIImage*)compressResolvingImage:(UIImage*)orginImage
{
if(orginImage == nil)return nil;
if(orginImage.size.width > SCREEN_WIDTH || orginImage.size.height >SCREEN_HEIGHT){
CGSize orginSize = orginImage.size;
if(orginSize.width >SCREEN_WIDTH){
orginSize.height = 1.0*SCREEN_WIDTH*orginSize.height/orginSize.width;
orginSize.width = SCREEN_WIDTH;
}else if (orginSize.height >SCREEN_HEIGHT){
orginSize.width = 1.0*SCREEN_HEIGHT*orginSize.width/orginSize.height;
orginSize.height = SCREEN_HEIGHT;
}
return [VAImageCompressTool ResizeImageWithImage:orginImage andSize:orginSize Scale:NO];
}else{
return orginImage;
}
}
总结:其实不管是图片本身大，或者分辨率大，都可以在最终显示处进行处理，比起把人家源码改来改去的，这样还算简单方便。
