Cocoa Programming for OS X: The Big Nerd Ranch Guide
by Aaron Hillegass, Adam Preble, Nate Chandler
Making Connections
Earlier, we described a XIB file as objects encoded as XML. But view objects alone do not create a user interface. You need connections to the controller layer so that a controller can execute the appropriate response to user actions. These connections will also be archived in the XIB file.
A connection lets two objects communicate. There are two kinds of connections that you can make in Interface Builder: outlets and actions. An outlet is a reference to a view object. An action is the name of the method that you want executed when a view object is interacted with.
In RandomPassword, you need two connections between the MainWindowController and other objects – an outlet that will point to the text field and ...