Gtk.Layout.prototype.get_vadjustment

function get_vadjustment():Gtk.Adjustment {
    // Gjs wrapper for gtk_layout_get_vadjustment()
}

This function should only be called after the layout has been placed in a Gtk.ScrolledWindow or otherwise configured for scrolling. It returns the Gtk.Adjustment used for communication between the vertical scrollbar and layout.

See Gtk.ScrolledWindow, Gtk.Scrollbar, Gtk.Adjustment for details.