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No new pictures today … the connector on my iPhone stopped working last night. Grrrrrr! That means I can’t run any of my apps written in class on a real device and am stuck with the simulator on the computer. It’s not the end of the world but some features (e.g., the camera and accelerometer) are not part of the simulator and, while I can code those bits into the exercise, it has less impact than it would otherwise.

Today started off with the camera … not much positive reinforcement with nothing to see in the simulator! 😉 But, the rest of the day went well. Maintaining the content of an application between executions (i.e., persisting data) was the primary focus. The two solutions we worked through were archiving (i.e., reading all the data in when the app loads and write it all when it unloads) and a quasi-database approach known as Core Data. Use archiving when your app contains a relatively small amount of data (e.g., a few hundred data items) and Core Data for larger volumes.

We seem to be on schedule. We’re a little more than 60% through the book after three days. A few chapters will be skipped (and left as exercises for me, the reader). The big topics remaining are animation, web services, push notifications and networking.