2.0版本2010年6月9日发布
2.0版本类结构上没有发生改变，最大改变增加了NSURLConnection网络请求和下面的一些优化
1. SDWebImageDownloaderDelegate.h 新增错误回调
@protocol SDWebImageDownloaderDelegate <NSObject>
@optional
- (void)imageDownloader:(SDWebImageDownloader *)downloader didFinishWithImage:(UIImage *)image;
//-----------------------2.0版本更新-新增错误回调-----------------------
- (void)imageDownloader:(SDWebImageDownloader *)downloader didFailWithError:(NSError *)error;
//---------------------------------end------------------------------
@end
2. SDWebImageManager.m去掉downloadWithURL、cancelForDelegate、didFinishWithImage方法的同步代码块
- (void)downloadWithURL:(NSURL *)url delegate:(id<SDWebImageManagerDelegate>)delegate{
if (url == nil || [failedURLs containsObject:url]){
return;
}
SDWebImageDownloader *downloader = [downloaderForURL objectForKey:url];
if (!downloader){
downloader = [SDWebImageDownloader downloaderWithURL:url delegate:self];
[downloaderForURL setObject:downloader forKey:url];
}
//-----------------------2.0版本更新-去除@synchronized同步块-----------------------
[delegates addObject:delegate];
[downloaders addObject:downloader];
//-----------------------------------end-----------------------------
}
- (void)cancelForDelegate:(id<SDWebImageManagerDelegate>)delegate{
//-----------------------2.0版本更新-去除@synchronized同步块-----------------------
NSUInteger idx = [delegates indexOfObjectIdenticalTo:delegate];
if (idx == NSNotFound){
return;
}
SDWebImageDownloader *downloader = [downloaders objectAtIndex:idx];
[delegates removeObjectAtIndex:idx];
[downloaders removeObjectAtIndex:idx];
if (![downloaders containsObject:downloader]){
[downloader cancel];
[downloaderForURL removeObjectForKey:downloader.url];
}
//-----------------------------------end-----------------------------
}
- (void)imageDownloader:(SDWebImageDownloader *)downloader didFinishWithImage:(UIImage *)image{
//-----------------------2.0版本更新-去除@synchronized同步块-----------------------
for (NSInteger idx = [downloaders count] - 1; idx >= 0; idx--){
SDWebImageDownloader *aDownloader = [downloaders objectAtIndex:idx];
if (aDownloader == downloader){
id<SDWebImageManagerDelegate> delegate = [delegates objectAtIndex:idx];
if (image && [delegate respondsToSelector:@selector(webImageManager:didFinishWithImage:)]){
[delegate performSelector:@selector(webImageManager:didFinishWithImage:) withObject:self withObject:image];
}
[downloaders removeObjectAtIndex:idx];
[delegates removeObjectAtIndex:idx];
}
}
//-----------------------------------end-----------------------------
if (image){
[[SDImageCache sharedImageCache] storeImage:image forKey:[downloader.url absoluteString]];
} else {
[failedURLs addObject:downloader.url];
}
[downloaderForURL removeObjectForKey:downloader.url];
}
3. SDWebImageDownloader.h 的父类由NSOperation更新为NSObject，同时添加了NSURLConnection成员变量。
//-----------------------2.0版本更新-新增网络请求，继承自NSObject-----------------------
@interface SDWebImageDownloader : NSObject{
@private
NSURL *url;
NSURLConnection *connection;
NSMutableData *imageData;
}
//-------------------------------end--------------------------------
@property (nonatomic, retain) NSURL *url;
@property (nonatomic, assign) id<SDWebImageDownloaderDelegate> delegate;
+ (id)downloaderWithURL:(NSURL *)url delegate:(id<SDWebImageDownloaderDelegate>)delegate;
//--------------2.0版本更新-新增网络请求，废弃setMaxConcurrentDownloads方法-----------------------
+ (void)setMaxConcurrentDownloads:(NSUInteger)max __attribute__((deprecated));
- (void)start;
- (void)cancel;
//-------------------------------end--------------------------------
@end
4. SDWebImageDownloader.m增加开始和取消网络请求方法start 、cancel和网络请求回调方法didReceiveData、connectionDidFinishLoading、didFailWithError
//--------------------------2.0版本更新-网络请求--------------------------
@interface SDWebImageDownloader ()
@property (nonatomic, retain) NSURLConnection *connection;
@property (nonatomic, retain) NSMutableData *imageData;
@end
//--------------------------------end---------------------------------
@implementation SDWebImageDownloader
@synthesize url, delegate, connection, imageData;
//--------------------------2.0版本更新-去除NSOperationQueue--------------------------
+ (id)downloaderWithURL:(NSURL *)url delegate:(id<SDWebImageDownloaderDelegate>)delegate{
SDWebImageDownloader *downloader = [[SDWebImageDownloader alloc] init];
downloader.url = url;
downloader.delegate = delegate;
[downloader start];
return downloader;
}
//--------------------------------end---------------------------------
+ (void)setMaxConcurrentDownloads:(NSUInteger)max{
// NOOP
}
//--------------------------2.0版本更新-网络请求--------------------------
- (void)start{
NSURLRequest *request = [[NSURLRequest alloc] initWithURL:url cachePolicy:NSURLRequestReloadIgnoringLocalCacheData timeoutInterval:15];
self.connection = [[NSURLConnection alloc] initWithRequest:request delegate:self startImmediately:NO];
[connection scheduleInRunLoop:[NSRunLoop currentRunLoop] forMode:NSRunLoopCommonModes];
[connection start];
if (connection){
self.imageData = [NSMutableData data];
} else {
if ([delegate respondsToSelector:@selector(imageDownloader:didFailWithError:)]){
[delegate performSelector:@selector(imageDownloader:didFailWithError:) withObject:self withObject:nil];
}
}
}
- (void)cancel{
if (connection){
[connection cancel];
self.connection = nil;
}
}
//--------------------------end--------------------------
//--------------------------2.0版本更新-请求回调--------------------------
- (void)connection:(NSURLConnection *)aConnection didReceiveData:(NSData *)data{
[imageData appendData:data];
}
- (void)connectionDidFinishLoading:(NSURLConnection *)aConnection{
UIImage *image = [[UIImage alloc] initWithData:imageData];
self.imageData = nil;
self.connection = nil;
if ([delegate respondsToSelector:@selector(imageDownloader:didFinishWithImage:)]){
[delegate performSelector:@selector(imageDownloader:didFinishWithImage:) withObject:self withObject:image];
}
}
- (void)connection:(NSURLConnection *)connection didFailWithError:(NSError *)error{
if ([delegate respondsToSelector:@selector(imageDownloader:didFailWithError:)]){
[delegate performSelector:@selector(imageDownloader:didFailWithError:) withObject:self withObject:error];
}
self.connection = nil;
self.imageData = nil;
}
//--------------------------end--------------------------
@end
5. SDImageCache.m新增后台通知UIApplicationDidEnterBackgroundNotification，当进入后台模式清空内存缓存，优化内存存储。
- (instancetype)init{
self = [super init];
if (self) {
//内存缓存
memCache = [[NSMutableDictionary alloc] init];
//磁盘缓存
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSCachesDirectory, NSUserDomainMask, YES);
//磁盘目录
diskCachePath = [[paths objectAtIndex:0] stringByAppendingPathComponent:@"ImageCache"];
//创建目录
if (![[NSFileManager defaultManager] fileExistsAtPath:diskCachePath]){
[[NSFileManager defaultManager] createDirectoryAtPath:diskCachePath withIntermediateDirectories:YES attributes:nil error:NULL];
}
//初始化缓存队列
cacheInQueue = [[NSOperationQueue alloc] init];
cacheInQueue.maxConcurrentOperationCount = 2;
//订阅应用程序事件
//应用程序终止，里面回调didReceiveMemoryWarning方法，清空内存
[[NSNotificationCenter defaultCenter] addObserver:self
selector:@selector(didReceiveMemoryWarning:)
name:UIApplicationDidReceiveMemoryWarningNotification
object:nil];
//应用程序终止，里面回调willTerminate方法，清空磁盘
[[NSNotificationCenter defaultCenter] addObserver:self
selector:@selector(willTerminate)
name:UIApplicationWillTerminateNotification
object:nil];
//-----------------------2.0版本更新-新增后台通知-----------------------
UIDevice *device = [UIDevice currentDevice];
if ([device respondsToSelector:@selector(isMultitaskingSupported)] && device.multitaskingSupported){
[[NSNotificationCenter defaultCenter] addObserver:self
selector:@selector(clearMemory)
name:UIApplicationDidEnterBackgroundNotification
object:nil];
}
//--------------------------------end--------------------------------
}
return self;
}
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