ios - iOS-显示来自“ALAssetLibrary”的图片

Question

我有ViewController1和ViewController2。ViewController1是UICollectionView，它使用ASAssetLibrary将缩略图加载到UICollectionViewCell中:

NSMutableArray *collector = [[NSMutableArray alloc] initWithCapacity:0];
ALAssetsLibrary *al = [TemplateEditBarController defaultAssetsLibrary];
[al enumerateGroupsWithTypes:ALAssetsGroupSavedPhotos
                  usingBlock:^(ALAssetsGroup *group, BOOL *stop)
 {
     [group enumerateAssetsUsingBlock:^(ALAsset *asset, NSUInteger index, BOOL *stop)
      {
          if (asset) {
              [collector addObject:asset];
          }
      }];
     assetsarray = collector;//<--assetsarray is local.
 }
                failureBlock:^(NSError *error) { NSLog(@"fail!");}
 ];

选择 cell时，我想将 NSString或 NSURL传递给 ViewController2，以便它将调用并显示全分辨率图像。但是当 NSLog网址时:

ALAsset* asset = backgroundsarray[row];
    ALAssetRepresentation *representation = [asset defaultRepresentation];
    NSURL *url = [representation url];
    newbg = [url absoluteString];//<-NSLog this.

我得到:

asset-library://asset/asset.JPG？id = 6E5438ED-9A8C-4ED0-9DEA-AB2D8F8A9360＆ext = JPG

我尝试更改为得到的 [url path]:

asset.JPG

如何获取实际的照片网址，以便可以转换为 NSString并传递给 ViewController2？

Answer 1

NSURL* aURL = [NSURL URLWithString:imagePath];        
ALAssetsLibrary *library = [[ALAssetsLibrary alloc] init];
[library assetForURL:aURL resultBlock:^(ALAsset *asset)
     {
         UIImage  *image = [UIImage imageWithCGImage:[[asset defaultRepresentation] fullScreenImage] scale:0.5 orientation:UIImageOrientationUp];             
         imageView.image=image;             

     }
            failureBlock:^(NSError *error)
     {
         // error handling
         NSLog(@"failure-----");
     }];