I have a model which is essentially three entities: Manufacturers <---->> Models <---->> Cars
The Manufacturer entity has property 'name'
The Model entity has property 'name'
The Car entity has properties 'registration' and 'milage'
I have a table view which displays on a each row a cars registration, milage, model and manufacturer, easily bound by eg:
Bind To: Cars, Controller Key: arrangedObjects, Model Key Path: model.manufaturer.name
I have another table view where I want to display the manufacturers and the total milage done by all their cars.
So the first column I have bound as:
Bind To: Manufacturers, Controller Key: arrangedObjects, Model Key Path: name
My problem occurs when then trying to bind the total milage. I have tried accessing it by:
Bind To: Manufacturers, Controller Key: arrangedObjects, Model Key Path: models.cars.@sum.milage
But this doesn't seem to work :( Am I going about this in completely the wrong way? Or do I need to add some methods to my Manufacturer, Model or Car classes?
Many thanks
EDIT: More info
Curiously binding a separate table to
Model - arrangedObjects - name
Model - arrangedObjects - cars.@sum.milage
Works, although an error is still thrown in the log: [<_NSFaultingMutableSet 0x1dbbb0> addObserver:forKeyPath:options:context:] is not supported. Key path: @sum.milage
