Head First iPhone and iPad Development, 3rd Edition

Chapter 7. Basic Core Data and Table View Cells: Reruns are hard to find

Just sit right back and you’ll hear a tale, a tale of a fateful trip. A challenge faced today is how to work with big data and make it presentable in a more appropriate format for mobile. There are lots of ways to do that, including manipulating the data and presenting it to the users in an easy to navigate and interpret way. TV presents one of those challenges because there are so many showings on the air. What’s a Gilligan fan to do?

This is your application

Gaming and reading apps aside, most applications on mobile are used to allow a user to sift efficiently through data on the go. Calorie tracking apps, calendar apps, mail, news readers, weather apps—they’re all some variation on that theme. Until now, we’ve worked with very basic storage, arrays, and plists.

Plists are great for just storing local data that is mostly numbers and strings. You want to get into storing photos or videos? Images? Plists are not a great solution. Performance starts to suffer and communicating data off the device is inefficient. Plists are XML files: they have to be loaded and saved in their entirety. Plists don’t support partial random access like a DB store.

This is your application on data

Most applications are driven ...