gtk-widget-toplevel (widget)

widget -- a gtk-widget object

The topmost ancestor of widget, or widget itself if there is no ancestor.

This function returns the topmost widget in the container hierarchy the widget is a part of. If the widget has no parent widgets, it will be returned as the topmost widget.

Note the difference in behavior versus the gtk-widget-ancestor function. The call (gtk-widget-ancestor widget "GtkWindow") would return nil if the widget was not inside a toplevel window, and if the window was inside a gtk-window derived widget which was in turn inside the toplevel gtk-window widget. While the second case may seem unlikely, it actually happens when a gtk-plug widget is embedded inside a gtk-socket widget within the same application.

To reliably find the toplevel gtk-window widget, use the gtk-widget-toplevel function and check the type of the result to be of "GtkWindow" type. For instance, to get the title of the toplevel window of the widget, one might use:

(defun get-widget-toplevel-title (widget)
  (let ((toplevel (gtk-widget-toplevel widget)))
    (when (eq (gtype "GtkWindow") (g-object-type toplevel))
      (gtk-window-title toplevel))))