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POAdding a float attribute to an entity in coreData and increment it on every addition of new Object
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copied!<p>I am new to coreData,I am working on a sample application where I have added a float type attribute called displayOrder to an entity called "Test". I want to increment this display order on adding each test Object. For this to happen, I have written the below code , but it is not working, I want to know where I am going wrong</p> <pre><code>- (void)insertNewObject:(NSString *)fileName { Test *testName = [NSEntityDescription insertNewObjectForEntityForName:@"Test" inManagedObjectContext:self.managedObjectContext]; [testName setName:fileName]; NSManagedObject *lastObject = [self.controller.fetchedObjects lastObject]; float lastObjectDisplayOrder = [[lastObject valueForKey:@"displayOrder"] floatValue]; NSLog(@"%f",lastObjectDisplayOrder); [testName setValue:[NSNumber numberWithDouble:lastObjectDisplayOrder + 1.0] forKey:@"displayOrder"]; // Save the context. NSError *error = nil; if (![self.managedObjectContext save:&error]) { // Replace this implementation with code to handle the error appropriately. // abort() causes the application to generate a crash log and terminate. You should not use this function in a shipping application, although it may be useful during development. NSLog(@"Unresolved error %@, %@", error, [error userInfo]); abort(); } } </code></pre> <p>Actually, the problem is it increments for the first time i.e from 0 to 1 but after this I get always 1.</p> <p>Regards Ranjit</p>

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