Question

I have a weird problem with FetchRequest template.

When i explicitly hardcode the variable I wish to substitute:

NSFetchRequest *fetchRequest = [[[Helper appDelegate] managedObjectModel]
                                fetchRequestFromTemplateWithName:@"srStoryForLesson"
                                substitutionVariables:[NSDictionary dictionaryWithObject:[NSNumber numberWithInt:2] forKey:@"number"]];

Every thing works fine.

But When I try to set a var as the Integer (as i want it to be dynamic) I get no results from the fetch.

NSInteger number = 2;

NSFetchRequest *fetchRequest = [[[Helper appDelegate] managedObjectModel]
                                fetchRequestFromTemplateWithName:@"srStoryForLesson"
                                substitutionVariables:[NSDictionary dictionaryWithObject:[NSNumber numberWithInt:number] forKey:@"number"]];

I can not understand what is wrong?

Thanks
Shani

Answer 1

The code you show should work fine. Your error is elsewhere.

I would recommend not using variable names like “number” because their generic nature risk naming collisions in Objective-C’s global name space. A more unique and descriptive name is safer and easier to read months down the road when you revisit the code.