Event ID Description
WINDOW_OPENEDoccurs the first time a window is made visible.
WINDOW_CLOSINGoccurs as a result of the close icon being selected or Close being selected from the window's system menu.
WINDOW_CLOSEDoccurs when the window has been closed.
WINDOW_ACTIVATEDoccurs when the window is activated - obtains the focus, in other words. When another GUI component has the focus, you could make the window obtain the focus by clicking on it, for example.
WINDOW_DEACTIVATEDoccurs when the window is deactivated - loses the focus, in other words. Clicking on another window would cause this event, for example.
WINDOW_GAINED_FOCUSoccurs when the window gains the focus. This implies that the window or one of its components will receive keyboard events.
WINDOW_LOST_FOCUSoccurs when the window loses the focus. This implies that keyboard events will not be delivered to the window or any of its components.
WINDOW_ICONIFIEDoccurs when the window is minimized and reduced to an icon.
WINDOW_DEICONIFIEDoccurs when the window is restored from an icon.
WINDOW_STATE_CHANGEDoccurs when the window state changes - when it is maximized or minimized, for instance.