GUIBaseContext :: doAfterSelect - Post-event handler after selecting data in a control

The handler is a reaction on the GEV_Select GUI event, which is fired, when an item in a list or tree is selected or after activating a tab in a tab control. The handler is typically used for synchronizing property windows with a tree or list, when this is not done automatically by the system. When being called from a tab control, the display level is set to the display level to be shown.

The handler should return one of the following values:

• -1 (not handled) - the event handler will be removed from the handler list and is not called anymore.
• 1 (error) - Returning an error has no effect for this events.
• 0 (ok) - Event handler terminated successfully.