gdk:toplevel-transient-for (object)

object -- a gdk:toplevel object
parent -- a toplevel gdk:surface object

The accessor for the transient-for slot of the gdk:toplevel class gets or sets the transient parent of the surface. Indicates to the window manager that surface is a transient dialog associated with the application surface parent. This allows the window manager to do things like center surface on parent and keep surface above parent.

See the gtk:window-transient-for function if you are using gtk:window or gtk:dialog widgets.