In MVC architechture, exactly how does a view tell the model (the document) that it needs to be updated? The examples in the book either assume that all relevant data is local to the view, or they assume that your application is editing a simple array so you can use core data to update a simple table.

In fact, how can any two objects communicate? All of the objects in a cocoa app appear to be instantiated by hidden code. And unless everything it to be done with notifications you need to know which object to pass messages to. For example, how does an NSView get a message to the corresponding NSDocument? An NSView can find the NSWindow. But while the book talks about an “automatic” NSWindowController, when you ask the NSWindow for its controller, you get null. More or less a dead end, unless you subclass the NSDocument for the sole purpose of creating a global pointer to itself.

I’m sure my confusion is due to years of Windows programming brain rot and that there are simple answers to these questions – they just arent in the book. Couldnt there have been an example of how a real world application might update a document in response to user events processed by a view?

Its a must read for anyone new to Mac or iPhone programming.