Hello All, I'm trying to query a Core Data database which contains geoLocation information for all of the objects of type "Photo" which are within a specified distance of a target point, using the following code.
- (NSArray*) photosNearLatitude: (NSNumber*) inLatitude longitude: (NSNumber*) inLongitude { NSExpression *theLHS = [NSExpression expressionForFunction: [NSExpression expressionForEvaluatedObject] selectorName: @"distanceFromLatitude:longitude:" arguments: [NSArray arrayWithObjects: [NSExpression expressionForConstantValue: inLatitude], [NSExpression expressionForConstantValue: inLongitude], nil]]; NSExpression* theRHS = [NSExpression expressionForConstantValue: [NSNumber numberWithDouble: 0.1]]; NSPredicate* thePredicate = [NSComparisonPredicate predicateWithLeftExpression: theLHS rightExpression: theRHS modifier: NSDirectPredicateModifier type: NSLessThanOrEqualToPredicateOperatorType options: 0]; NSManagedObjectContext* theManagedObjectContext = [self managedObjectContext]; NSFetchRequest* theFetch = [[[NSFetchRequest alloc] init] autorelease]; theFetch.entity = [NSEntityDescription entityForName: @"Photo" inManagedObjectContext: theManagedObjectContext]; theFetch.predicate = thePredicate; NSError* theError = NULL; NSArray* theResults = [theManagedObjectContext executeFetchRequest: theFetch error: &theError]; return theResults; } The "Photo" class has the following selector. - (NSNumber*) distanceFromLatitude: (NSNumber*) inLatitude longitude: (NSNumber*) inLongitude My problem is that when I call "executeFetchRequest", an exception occurs: 2009-11-25 16:55:20.633 Serendipity[8498:a0f] Unsupported function expression FUNCTION(SELF, "distanceFromLatitude:longitude:" , 47.71283333333334, -122.225) -[Photo distanceFromLatitude:longitude:] is never called. Can anyone suggest what might be going wrong? - Ron Aldrich _______________________________________________ Cocoa-dev mailing list (Cocoa-dev@lists.apple.com) Please do not post admin requests or moderator comments to the list. Contact the moderators at cocoa-dev-admins(at)lists.apple.com Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com This email sent to arch...@mail-archive.com