解决MWPhotoBrowser中的SDWebImage加载大图导致的内存警告问题

标签：mwphotobrowser   iosdevtip   sdwebimage   内存警告   

    Future Enhancements

        LRU memory cache cleanup instead of reset on memory warning

    How to disable "memory cache"?  I don't want memory cache,  it used a lot of memory and got memory waring easily,  disk is enough for me...

    There is no way to disable the memory cache. But the cache is designed to flush itself when you get a memory warning, so you shouldn't need to worry it.

- (void)connectionDidFinishLoading:(NSURLConnection *)aConnection {
       SDWebImageDownloaderCompletedBlock completionBlock = self.completedBlock;
       @synchronized(self) {
           CFRunLoopStop(CFRunLoopGetCurrent());
           self.thread = nil;
           self.connection = nil;
           [[NSNotificationCenter defaultCenter] postNotificationName:SDWebImageDownloadStopNotification object:nil];
       }
       
       if (![[NSURLCache sharedURLCache] cachedResponseForRequest:_request]) {
           responseFromCached = NO;
       }
       
       if (completionBlock)
       {
           if (self.options & SDWebImageDownloaderIgnoreCachedResponse && responseFromCached) {
               completionBlock(nil, nil, nil, YES);
           }
           else {
               UIImage *image = [UIImage sd_imageWithData:self.imageData];
               NSString *key = [[SDWebImageManager sharedManager] cacheKeyForURL:self.request.URL];
               image = [self scaledImageForKey:key image:image];
               
               // Do not force decoding animated GIFs
               if (!image.images) {
                   image = [UIImage decodedImageWithImage:image];
               }
               if (CGSizeEqualToSize(image.size, CGSizeZero)) {
                   completionBlock(nil, nil, [NSError errorWithDomain:@"SDWebImageErrorDomain" code:0 userInfo:@{NSLocalizedDescriptionKey : @"Downloaded image has 0 pixels"}], YES);
               }
               else {
                   completionBlock(image, self.imageData, nil, YES);
               }
           }
       }
       self.completionBlock = nil;
       [self done];
    }

+ (UIImage *)sd_imageWithData:(NSData *)data {
       UIImage *image;
       NSString *imageContentType = [NSData sd_contentTypeForImageData:data];
       if ([imageContentType isEqualToString:@"image/gif"]) {
           image = [UIImage sd_animatedGIFWithData:data];
       }
    #ifdef SD_WEBP
       else if ([imageContentType isEqualToString:@"image/webp"])
       {
           image = [UIImage sd_imageWithWebPData:data];
       }
    #endif
       else {
           image = [[UIImage alloc] initWithData:data];
           UIImageOrientation orientation = [self sd_imageOrientationFromImageData:data];
           if (orientation != UIImageOrientationUp) {
               image = [UIImage imageWithCGImage:image.CGImage
                                           scale:image.scale
                                     orientation:orientation];
           }
       }


       return image;
    }

+(UIImage *)compressImageWith:(UIImage *)image
    {
       float imageWidth = image.size.width;
       float imageHeight = image.size.height;
       float width = 640;
       float height = image.size.height/(image.size.width/width);

       float widthScale = imageWidth /width;
       float heightScale = imageHeight /height;
       
       // 创建一个bitmap的context
       // 并把它设置成为当前正在使用的context
       UIGraphicsBeginImageContext(CGSizeMake(width, height));
       
       if (widthScale > heightScale) {
           [image drawInRect:CGRectMake(0, 0, imageWidth /heightScale , height)];
       }
       else {
           [image drawInRect:CGRectMake(0, 0, width , imageHeight /widthScale)];
       }
       
       // 从当前context中创建一个改变大小后的图片
       UIImage *newImage = UIGraphicsGetImageFromCurrentImageContext();
       // 使当前的context出堆栈
       UIGraphicsEndImageContext();
       
       return newImage;
       
    }

if (data.length/1024 > 1024) {
               image = [self compressImageWith:image];
           }

 UIImage *image = [UIImage sd_imageWithData:self.imageData];

      //将等比压缩过的image在赋在转成data赋给self.imageData
      NSData *data = UIImageJPEGRepresentation(image, 1);
      self.imageData =  [NSMutableData dataWithData:data];

解决MWPhotoBrowser中的SDWebImage加载大图导致的内存警告问题

标签：mwphotobrowser   iosdevtip   sdwebimage   内存警告   

原文地址：http://blog.csdn.net/iosdevtip/article/details/43017139