Summary

In this hour you learned how to switch views using view controllers. Because most applications display many views, this is a key topic. As you’ll have noticed, it isn’t hard, but it does involve a lot of details. Make sure you understand the difference between views (tab bars and navigation bars) and view controllers (tab bar controllers and navigation controllers), which was explained this hour. Navigation controllers and tab controllers are view controllers that manage other view controllers, which can build the appropriate subviews. This abstraction helps Cocoa Touch minimize memory usage while reducing the amount of code you must write.

In the next hour, you’ll study how Cocoa Touch provides undo and redo functionality, and you’ll learn how to edit tables.