CustomerListController.m is a table view
controller that displays the customer data in the client database. The
viewWillAppear method uses the Object
API to query the database for a list of all Customer objects, and builds an
NSArray that is used by this class as the datasource for displaying the
table view.
If a row is tapped, the accessoryButtonTappedForRowWithIndexPath method is executed,
which pushes a DetailController onto the
stack to display additional information and allow the data to be
modified.