GtkWidget::unmap
This method destroys information regards the dimensions of the screen
area where the widget is displayed . It is mostly used internally,
being one of the methods that is called as part of the
hide() routine. It causes
the "unmap" signal to be
emitted by the widget, which in turn switches a flag causing the
widget to be unmapped.
At the point of a widget's becoming unmapped, the
GdkEvent GDK_UNMAP is
triggered, causing the
"unmap-event" signal to
also be emitted by that widget. Use this signal to trigger functions
that rely on the unmap event having occurred.
See also: map()