Spika-iOS : "incompatible block pointer types" - ios

Question

I have downloaded the 'Spika' script for iOS and Android but have run into the following issue. When trying to compile I get the following error :
Incompatible block pointer types sending 'int (^)(ModelMessage *__strong, ModelMessage *__strong)' to parameter of type 'NSComparator' (aka 'NSComparisonResult (^)(__strong id, __strong id)')
I have tried to resolve the issue by changing it to NSComparisonResult but cannot seem to get my head around what the issue is.
Here is the code :
NSMutableArray *removeTarget = [[NSMutableArray alloc] init];
for(int i = 0; i < [result count] ; i++){
ModelMessage *message = [result objectAtIndex:i];
if(message.valid == NO)
[removeTarget addObject:message];
}
for(int ii = 0; ii < [removeTarget count] ; ii++){
[result removeObject:[removeTarget objectAtIndex:ii]];
}
NSArray *sortedAry = [result sortedArrayUsingComparator:^(ModelMessage *a, ModelMessage *b) {
return a.modified> b.modified;
}];
int fetchNum = PagingMessageFetchNum;
if(fetchNum > sortedAry.count)
fetchNum = sortedAry.count;
return sortedAry;
//return [sortedAry subarrayWithRange:NSMakeRange(0, fetchNum)];
}
The issue lies in :
NSArray *sortedAry = [result sortedArrayUsingComparator:^(ModelMessage *a, ModelMessage *b) {
return a.modified> b.modified;
Any help would be greatly appreciated. Thanks guys.

Answer 1

You should return not a BOOL result as in your code above.
The result must be of type NSComparisonResult which is enum
enum {
NSOrderedAscending = -1,
NSOrderedSame,
NSOrderedDescending
};
In your case the sorting block should look like that
NSArray *sortedAry = [result sortedArrayUsingComparator:^(ModelMessage *a, ModelMessage *b) {
if(a.modified<b.modified)
return NSOrderedAscending;
else if(a.modified>b.modified)
return NSOrderedDescending;
else
return NSOrderedSame;
}];