Windows Installer defines a limited number of events that your UI controls can listen out for or trigger. For example, a progress bar can listen for actions that say progress has taken place, and then react by showing more ticks. Or, a button can trigger an action that closes the current window. Listening for an event is known as subscribing and triggering one is known as publishing.
Because these events happen within the
Control elements they're known as Control Events. We've covered several examples of control events already in Chapter 7, Using UI Controls, but we'll cover others that you haven't seen and show how the whole process works. In this chapter, we will: