gdk:window-set-background (window color)

window -- a gdk:window object
color -- a gdk:color instance

Sets the background color of the window. However, when using GTK, set the background of a widget with the gtk:widget-modify-bg function, if you are implementing an application, or the gtk:style-context-set-background function, if you are implementing a custom widget.

See also the gdk:window-background-pattern function. The gdk:window-set-background function has been deprecated since version 3.4 and should not be used in newly written code. Use the gdk:window-set-background-rgba function instead.