onshow
onactive是在取得焦点的时候激活的
See help in ;delphi
Occurs when the form becomes active.
property OnActivate: TNotifyEvent;
Description
Use OnActivate to perform special
processing when the form receives
focus. A form becomes active when
;focus is transferred to it (when
;the user clicks on the form, for
example).
Note: The OnActivate event of the
application (TApplication), not the fo
rm, occurs when control switches ;from another application.