Note that setting this to %TRUE doesn’t mean the widget is
actually viewable, see [method@Gtk.Widget.get_visible].
This function simply calls [method@Gtk.Widget.show] or
[method@Gtk.Widget.hide] but is nicer to use when the
visibility of the widget depends on some condition.
Sets the visibility state of @widget.
Note that setting this to %TRUE doesn’t mean the widget is actually viewable, see [method@Gtk.Widget.get_visible].
This function simply calls [method@Gtk.Widget.show] or [method@Gtk.Widget.hide] but is nicer to use when the visibility of the widget depends on some condition.