How do I break through the enumeration going on for ALAssetsLibrary enumerateAssets method with a boolean set. Can I just get out of the loop?
CODE:
[self.library enumerateGroupsWithTypes:ALAssetsGroupSavedPhotos usingBlock:^(ALAssetsGroup *group, BOOL *stop) {
@try {
if(group != nil) {
@autoreleasepool {
int newNumberOfPhotos = [group numberOfAssets];
if (self.numberOfPhotosInSavedPhotos < newNumberOfPhotos) {
//only new photos
NSRange range = NSMakeRange(self.numberOfPhotosInSavedPhotos, newNumberOfPhotos-self.numberOfPhotosInSavedPhotos);
NSIndexSet *indexSet = [NSIndexSet indexSetWithIndexesInRange:range];
[group enumerateAssetsAtIndexes:indexSet options:0 usingBlock:^(ALAsset *result, NSUInteger index, BOOL *stop) {
@autoreleasepool {
if(someCondition) {
//get out of the enumeration block (that is, exit the method) or go to complete block
}
NSString *assetType = [result valueForProperty:ALAssetPropertyType];
}
} ];
}
}
} else {
//enumeration ended
}
}
@catch (NSException *e) {
NSLog(@"exception streaming: %@", [e description]);
}
}failureBlock:^(NSError *error){
NSLog(@"Error retrieving albums stream: %@", [error description]);
if (error.code==-3312 || error.code==-3311) {
}
}];
To stop the assets enumeration, just set *stop = YES
in the enumeration block.
If you want to stop both the outer and the inner enumeration, use different names for the stop variable and set both to YES
:
[self.library enumerateGroupsWithTypes:ALAssetsGroupSavedPhotos usingBlock:^(ALAssetsGroup *group, BOOL *outerStop) {
...
[group enumerateAssetsAtIndexes:indexSet options:0 usingBlock:^(ALAsset *result, NSUInteger index, BOOL *innerStop) {
if (someCondition) {
*innerStop = YES;
*outerStop = YES;
} else {
// process asset
}
}
}
Remarks: The @try/@catch
block should normally not be necessary if you don't have a programming error inside your loops.
Your check for "new photos" looks suspicious, because the number of assets in each group is compared with the same number self.numberOfPhotosInSavedPhotos
, perhaps you should check that part again.
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