Add |-loadAssetsForProperty:fromAlbum:completion:|

Kjuly · Aug 30, 2015 · 8c12cd2 · 8c12cd2
1 parent f943321
commit 8c12cd2
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diff --git a/ALAssetsLibrary-CustomPhotoAlbum/ALAssetsLibrary+CustomPhotoAlbum.h b/ALAssetsLibrary-CustomPhotoAlbum/ALAssetsLibrary+CustomPhotoAlbum.h
@@ -61,6 +61,16 @@
          completion:(ALAssetsLibraryWriteImageCompletionBlock)completion
             failure:(ALAssetsLibraryAccessFailureBlock)failure;
 
+/*! Loads assets w/ desired property from the assets group (album)
+ *
+ * \param property   Property for the asset, refer to ALAsset.h, if not offered, just return instances of ALAsset
+ * \param albumName  Custom album name
+ * \param completion Block to be executed when succeed or failed to load assets from target album
+ */
+- (void)loadAssetsForProperty:(NSString *)property
+                    fromAlbum:(NSString *)albumName
+                   completion:(void (^)(NSMutableArray *array, NSError *error))completion;
+
 /*! Loads assets from the assets group (album)
  *
  * \param albumName Custom album name

diff --git a/ALAssetsLibrary-CustomPhotoAlbum/ALAssetsLibrary+CustomPhotoAlbum.m b/ALAssetsLibrary-CustomPhotoAlbum/ALAssetsLibrary+CustomPhotoAlbum.m
@@ -306,6 +306,45 @@ - (void)addAssetURL:(NSURL *)assetURL
                     failureBlock:failure];
 }
 
+- (void)loadAssetsForProperty:(NSString *)property
+                    fromAlbum:(NSString *)albumName
+                   completion:(void (^)(NSMutableArray *, NSError *))completion
+{
+  ALAssetsLibraryGroupsEnumerationResultsBlock block = ^(ALAssetsGroup *group, BOOL *stop) {
+    // Checking if library exists
+    if (group == nil) {
+      *stop = YES;
+      return;
+    }
+
+    // If we have found library with given title we enumerate it
+    if ([albumName compare:[group valueForProperty:ALAssetsGroupPropertyName]] == NSOrderedSame) {
+      NSMutableArray * array = [[NSMutableArray alloc] init];
+      [group enumerateAssetsUsingBlock:^(ALAsset *result, NSUInteger index, BOOL *stop) {
+        // Checking if group isn't empty
+        if (! result) return;
+
+        [array addObject:(property ? ([result valueForProperty:property] ?: [NSNull null]) : result)];
+      }];
+
+      // Execute the |completion| block
+      if (completion) completion(array, nil);
+
+      // Album was found, bail out of the method
+      *stop = YES;
+    }
+  };
+
+  ALAssetsLibraryAccessFailureBlock failureBlock = ^(NSError *error) {
+    NSLog(@"%s: %@", __PRETTY_FUNCTION__, [error localizedDescription]);
+    if (completion) completion(nil, error);
+  };
+
+  [self enumerateGroupsWithTypes:ALAssetsGroupAll
+                      usingBlock:block
+                    failureBlock:failureBlock];
+}
+
 - (void)loadImagesFromAlbum:(NSString *)albumName
                  completion:(void (^)(NSMutableArray *, NSError *))completion
 {