gtk:text-view-add-child-in-window (view child wtype xpos ypos)

view -- a gtk:text-view widget
child -- a gtk:widget object
wtype -- a gtk:text-window-type value for the window type the child widget should appear in
xpos -- an integer for the x position of the child widget in window coordinates
ypos -- an integer for the y position of the child widget in window coordinates

Adds a child widget at fixed coordinates in one of the windows of the text view. The window must have nonzero size, see the gtk:text-view-border-window-size function. Note that the child widget coordinates are given relative to the GDK window in question, and that these coordinates have no sane relationship to scrolling. When placing a child widget in a :widget window, scrolling is irrelevant, the child widget floats above all scrollable areas. But when placing a child widget in one of the scrollable windows, border windows or text window, you will need to compute the correct position of the child widget in text buffer coordinates any time scrolling occurs or text buffer changes occur, and then call the gtk:text-view-move-child function to update the position of the child widget.