To select a method whose execution you want to watch, view the Call Stack window and then select one of the methods in the list.
To display the Call Stack window if it is not currently displayed
Select the View menu Call Stack command.
As the methods are selected in the Call Stack window, the Watches list is updated to reflect the values that are within the scope of the selected method. If no method is selected in the Call Stack window, the values are displayed for the method that is currently executing.
Items that can be watched are:
Method parameters
Local variables
Double-click on an entry in the Call Stack window to display the Inspector window for the receiver of that method. (For details, see "Inspecting Object Instances", in Chapter 6.)