nsmanagedobject

I'm wanting to write a "management" game that utilizes Core data heavily. The game requires a pre-set, pre-defined dataset that cannot be changed by the user/system; it is used to seed the game with data and is meant to be read-only. The best example I can give is a football management game, but it could be anything. In some football management sims they give you scenarios and pre-set datasets. As the user proceeds through the game they can save/load their progress which is saved to the core data. In addition to this, the user can receive updates to the pre-defined data or can purchase

As pointed out in another question on SO (and the Apple docs ), NSManagedObject instances do not hold a strong reference to the NSManagedObjectContext from which they originated. On first blush, this seems like a strange decision, since NSManagedObject instances are nearly useless without their context , since it leads to confusing bugs such as faults not firing when they should . Can anyone provide some background on why this is the case? Would it be dangerous to implement an NSManagedObject subclass that automatically holds a strong reference to its NSManagedObjectContext ? Edit: thanks to

My problem is similar to: Problem creating NSManagedObject derived class I have setup a NSManagedObject in Core Data and have a class for it. However, instead of creating an identical NSObject class, I'd like to use the NSManagedObject class, but I don't want to create the entity and save it. I just want to use it for an array, only when I need to save the object in Core Data do I want to use insertEntity: Store *store = [[Store alloc] init]; It's giving me the following error: CoreData: error: Failed to call designated initializer on NSManagedObject class 'Store' Is there a way to either

I built a simple mac data entry tool I use with an iPhone application. I've recently added thumbnail which I added via an Image Well using simple bindings. Its a transformable data type which seems to work fine. The iPhone application however won't show the images. The attribute isn't null but I can't get an image to appear. The following is for cellForRowAtIndexPath static NSString *CellIdentifier = @"Cell"; UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier]; if (cell == nil) { cell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault

Now that Xcode4 is publicly available I'm moving this question out of Apple's secret dev forum: Can someone explain why the code generated in the following procedure is different than in Xcode3? Is the code better or might this be a bug? I use Core Data custom managed classes and this was the procedure I followed in Xcode3: Go to the model editor Select the entity you wish to generate source code for Go to File->New->New Files Choose managedobject class (or whatever it was, I can't open xcode3 anymore to verify) Select entities you wish to generate (the previously selected entity in step 2 is

My Cocoa/Application has a Managed Object Context on the main thread. When I need to update my data my program will: Start a new thread Receive new data from a server Create a new Managed Object Context Send a notification to the main thread in order to merge the two context This is the function that receive the notification on the main thread - (void)loadManagedObjectFromNotification:(NSNotification *)saveNotification { if ([NSThread isMainThread]) { [self.managedObjectContext mergeChangesFromContextDidSaveNotification:saveNotification]; } else { [self performSelectorOnMainThread:@selector

I released my first solo iPhone app last week that calculates 12V Marine and Boat Battery usage . I had tested it vigorously on the simulator and on my iPhone, and when I was comfortable all was well, I archived the app and released it to Apple. When users started using the app, they noted a calculation was not working as expected. The below code, which is a method on a NSManagedObject model, was producing a DIFFERENT output when released to when in debug. The below should sum up the total of the related Discharge items - but if there are no BBDischarge items, then it should return zero.