在iOS 7中使用資產URL獲取圖像（UIImage）

Question

我的相冊中有一些圖像。 我已經檢索了所有這些資產網址。我想使用資產網址獲取特定圖像...下面的代碼給了我資產網址..

    ALAssetRepresentation *defaultRepresentation = [asset defaultRepresentation];

                      NSString *uti = [defaultRepresentation UTI];
                      NSURL *URL = [[asset valueForProperty:ALAssetPropertyURLs] valueForKey:uti];

現在使用這個URL，我怎樣才能獲得圖像（UIImage）？

Answer 1

獲取網址，

NSURL *url= (NSURL*) [[asset valueForProperty:ALAssetPropertyURLs] valueForKey:[[[asset valueForProperty:ALAssetPropertyURLs] allKeys] objectAtIndex:0]];

並從下面的網址獲取圖像。

ALAssetsLibraryAssetForURLResultBlock resultblock = ^(ALAsset *myasset)
{
    ALAssetRepresentation *rep = [myasset defaultRepresentation];
    @autoreleasepool {
        CGImageRef iref = [rep fullScreenImage];
        if (iref) {
            UIImage *image = [UIImage imageWithCGImage:iref];
            self.loadedImage = image;
            dispatch_async(dispatch_get_main_queue(), ^{
                //UIMethod trigger...
            });
            iref = nil;
        }
    } 
};

ALAssetsLibraryAccessFailureBlock failureblock  = ^(NSError *myerror)
{
    NSLog(@"Can't get image - %@",[myerror localizedDescription]);
};

ALAssetsLibrary* assetslibrary = [[ALAssetsLibrary alloc] init];
[assetslibrary assetForURL:yourUrl
               resultBlock:resultblock
              failureBlock:failureblock];

Answer 2

UIImage *img = [UIImage imageWithCGImage:[[myAsset defaultRepresentation] fullResolutionImage]

希望這可以幫助