More events

The user clicking on a button is common event, but the computer can recognize and act upon many types of event. For example, when you roll the mouse over this picture:

a blue car is displayed, and when you roll it off the picture, a red car is displayed.

This example illustrates two events: the user rolling the mouse over the picture and the user rolling it back off. The programmer had to write an event handler subprogram for each of these events:

  1. on MouseOver event: display a picture of a blue car
  2. on MouseOut event: display a picture of a red car