About events for windows and controls
Windows have several events including Open, which is triggered
when the window is opened (before it is displayed), and Close, which
is triggered when the window is closed. For example, you might connect
to a database and initialize some values in the window’s Open event,
and disconnect from a database in the Close event.
Each type of control also has its own set of events. Buttons,
for example, have Clicked events, which trigger when a user clicks the
button. SingleLineEdits and MultiLineEdits have Modified events, which
trigger when the contents of the edit control change.
Defining your own events
You can also define your own events, called user events, for a
window or control, then use the EVENT keyword to trigger your user
event.
For example, assume that you offer the user several ways to
update the database from a window, such as clicking a button or
selecting a menu item. In addition, when the user closes the window,
you want to update the database after asking for confirmation. You
want the same type of processing to happen after different system
events.
You can define a user event for the window, write a script for
that event, and then everywhere you want that event triggered, use the
EVENT keyword.
To learn how to use user events, see Working with User Events.