最新一张照片 #获取最新照片 #最后照片

最新一张照片.m

- (void)showLastImageForImageView:(UIImageView *)imageView
{
    
    
        ALAssetsLibraryAccessFailureBlock failureblock = ^(NSError *myerror){
            NSLog(@"相册访问失败 =%@", [myerror localizedDescription]);
            if ([myerror.localizedDescription rangeOfString:@"Global denied access"].location!=NSNotFound) {
                NSLog(@"无法访问相册.请在'设置->定位服务'设置为打开状态.");
            }else{
                NSLog(@"相册访问失败.");
            }
        };

    
   
    self.library=[TodayViewController defaultAssetsLibrary];
    
    
    // Block called for every asset selected
    void (^selectionBlock)(ALAsset*, NSUInteger, BOOL*) = ^(ALAsset* asset,NSUInteger index,BOOL* innerStop) {
        
        
        NSLog(@"相册：%lu",(unsigned long)index);
        
        // The end of the enumeration is signaled by asset == nil.
        if (asset == nil) {
            return;
        }
        
//        ALAssetRepresentation* representation = [asset defaultRepresentation];
//        
//        // Retrieve the image orientation from the ALAsset
//        UIImageOrientation orientation = UIImageOrientationUp;
//        NSNumber* orientationValue = [asset valueForProperty:@"ALAssetPropertyOrientation"];
//        if (orientationValue != nil) {
//            orientation = [orientationValue intValue];
//        }
//        
//        CGFloat scale  = 0.5;
//        UIImage* image = [UIImage imageWithCGImage:[representation fullResolutionImage]
//                                             scale:scale orientation:orientation];
//        
//        // do something with the image
//        
//        __weak typeof(imageView)weakImageView = imageView;
//        
//        dispatch_async(dispatch_get_main_queue(), ^{
//        
//            if (image) {
//                
//                weakImageView.image=image;
//                
//                NSLog(@"图片有效---->%@",image);
//                
//            }else
//            {
//                NSLog(@"图片为空---->%@",image);
//                
//            }
//            
//        });
        __weak typeof(imageView)weakImageView = imageView;
        
        weakImageView.image=[UIImage imageWithCGImage:asset.thumbnail];
        
        
    };
    
    
    
    
    
    
    
    
//    dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{
    
        
       
        
        
        
        // Block called when enumerating asset groups
        void (^enumerationBlock)(ALAssetsGroup*, BOOL*) = ^(ALAssetsGroup* group, BOOL* stop) {
            // Within the group enumeration block, filter to enumerate just photos.
            [group setAssetsFilter:[ALAssetsFilter allPhotos]];
            
            // Get the photo at the last index
            NSUInteger index              = [group numberOfAssets] - 1;
            NSIndexSet* lastPhotoIndexSet = [NSIndexSet indexSetWithIndex:index];
            [group enumerateAssetsAtIndexes:lastPhotoIndexSet options:0 usingBlock:selectionBlock];
        };
        
        
        
        
        
        // Enumerate just the photos and videos group by using ALAssetsGroupSavedPhotos.
        [self.library enumerateGroupsWithTypes:ALAssetsGroupSavedPhotos
                                    usingBlock:enumerationBlock
                                  failureBlock:^(NSError* error) {
                                      // handle error
                                  }];
        

        
        
        
        
//    });
    
    
    
}


+ (ALAssetsLibrary *)defaultAssetsLibrary {
    static dispatch_once_t pred = 0;
    static ALAssetsLibrary *library = nil;
    dispatch_once(&pred, ^{
        library = [[ALAssetsLibrary alloc] init];
    });
    return library;
}