Getting Ready For Core Data In 3.0
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As noted by Jeff LaMarche, iPhone 3.0 includes the previously-absent Core Data API.
While Core Data is a core component to OS-X programming, many iPhone developers will be unfamiliar with it, having skipped directly to Cocoa Touch without ever touching Cocoa.
We’ve put together a compact set of three resources that introduce — from decidedly different angles — the key concepts behind Core Data to help you get ready for 3.0:
A Quick Overview of Basic Core Data Concepts, by Scott Stevenson, describes Core Data in Object-Relational Mapping (ORM) terms. If you think in terms of models and relationships (or “associations”) between those models, this article is a great place to start.
Cocoa Dev Central’s Core Data Class Overview presents a well-organized high-level view and progressively takes you deeper until you’ve learned enough of the essentials to get to work.
Apple’s Core Data Programming Guide is organized along Core Data’s two main areas of functionality: object graph management and object persistence.
Core Data and Cocoa Bindings, which automatically wire up UI elements and Core Data values, are often presented together in tutorials for OS-X. While Core Data for the iPhone was plainly visible in the slides at Apple’s public preview event, Cocoa Bindings for iPhone was not to be found.
If 3.0 does not contain Cocoa Bindings then some of what you read in tutorials and elsewhere may not be applicable to the iPhone and you’ll be responsible for manually getting/setting values, saving, etc.
This is interesting – not sure if it will be necessary to use this sort of data access method now that I went through the trouble of learning how to work with SQLite.