Section 15.7 Low-Level Event Processing
In the previous lessons you learned how to associate simple user actions with the most common user events, such as clicking on a button. For simple GUI programs this is typically sufficient. But for more complex programs you might need to process “lower level” events, such as recognizing when the user's cursor is over a widget, or when a widget becomes the focus of user input. To handle these types of events you need to implement event binding. This lesson provides an overview of how to process any event that happens on a computer. We will not use these techniques in most of the simple GUI programs we discuss, but you should be aware of what is possible.