2.2版本2010年8月29日发布
更新说明：如果图片格式是PNG或GIF，当存储到磁盘进行缓存时候，不要将图像转换为JPEG，因为他能够节省CPU和内存以及alpha通道/图像的清晰度。
1. SDWebImageDownloader 新增加了属性，在主线程下载和优化了回调处理
@property (nonatomic, retain) NSURL *url;
@property (nonatomic, assign) id<SDWebImageDownloaderDelegate> delegate;
//-------------2.2版本更新-新增-新增属性-------------------
@property (nonatomic, retain) NSMutableData *imageData;
//--------------------------end-------------------------
+ (id)downloaderWithURL:(NSURL *)url delegate:(id<SDWebImageDownloaderDelegate>)delegate{
SDWebImageDownloader *downloader = [[SDWebImageDownloader alloc] init];
downloader.url = url;
downloader.delegate = delegate;
//-------------2.2版本更新-在主线程下载-------------------
[downloader performSelectorOnMainThread:@selector(start) withObject:nil waitUntilDone:YES];
//--------------------------end-------------------------
return downloader;
}
- (void)connectionDidFinishLoading:(NSURLConnection *)aConnection{
//------------------2.2版本更新-优化----------------------
self.connection = nil;
//下载器下载完成
if ([delegate respondsToSelector:@selector(imageDownloaderDidFinish:)]){
[delegate performSelector:@selector(imageDownloaderDidFinish:) withObject:self];
}
if ([delegate respondsToSelector:@selector(imageDownloader:didFinishWithImage:)]){
UIImage *image = [[UIImage alloc] initWithData:imageData];
[delegate performSelector:@selector(imageDownloader:didFinishWithImage:) withObject:self withObject:image];
}
//--------------------------end--------------------------
}
2. 缓存器->SDImageCache 新增了属性和方法重载，增加了二进制NSData数据存储到磁盘
@interface SDImageCache : NSObject{
NSMutableDictionary *memCache;
NSString *diskCachePath;
NSOperationQueue *cacheInQueue;
//-------------2.2版本更新-新增-方法重载-功能抽象-------------------
NSMutableDictionary *storeDataQueue;
//--------------------------------end------------------------------
}
//-------------2.2版本更新-新增-方法重载-功能抽象-------------------
- (void)storeImage:(UIImage *)image imageData:(NSData *)data forKey:(NSString *)key toDisk:(BOOL)toDisk;
//-------------------------------end---------------------------
//-------------2.2版本更新-新增-方法重载-功能抽象-------------------
- (void)storeImage:(UIImage *)image forKey:(NSString *)key{
[self storeImage:image imageData:nil forKey:key toDisk:YES];
}
- (void)storeImage:(UIImage *)image forKey:(NSString *)key toDisk:(BOOL)toDisk{
[self storeImage:image imageData:nil forKey:key toDisk:toDisk];
}
- (void)storeImage:(UIImage *)image imageData:(NSData *)data forKey:(NSString *)key toDisk:(BOOL)toDisk{
if (!image || !key){
return;
}
if (toDisk && !data){
return;
}
[memCache setObject:image forKey:key];
if (toDisk){
[storeDataQueue setObject:data forKey:key];
[cacheInQueue addOperation:[[NSInvocationOperation alloc] initWithTarget:self selector:@selector(storeKeyToDisk:) object:key]];
}
}
//-------------------------------end---------------------------
- (void)storeKeyToDisk:(NSString *)key{
//-------------2.2版本更新-磁盘缓存-------------------
NSFileManager *fileManager = [[NSFileManager alloc] init];
NSData *data = [storeDataQueue objectForKey:key];
if (data){
//存储二进制->NSData
[fileManager createFileAtPath:[self cachePathForKey:key] contents:data attributes:nil];
@synchronized(storeDataQueue){
[storeDataQueue removeObjectForKey:key];
}
//----------------------end------------------------
} else {
//存储图片->UIImage
UIImage *image = [self imageFromKey:key fromDisk:YES];
if (image){
[fileManager createFileAtPath:[self cachePathForKey:key] contents:UIImageJPEGRepresentation(image, (CGFloat)1.0) attributes:nil];
}
}
}
3. SDWebImageDownloaderDelegate 新增了回调imageDownloaderDidFinish针对于imageData它而设计，后面版本迭代会更新具体实现暂时没有。
//-----------------------2.2版本更新-下载完成回调-----------------------
- (void)imageDownloaderDidFinish:(SDWebImageDownloader *)downloader;
//---------------------------------end------------------------------
