setTransientFor
Sets a transient-for parent.
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 ../gtk4/method.Window.set_transient_for.html if you’re using ../gtk4/class.Window.html.
Parameters
parent
another toplevel GdkSurface