#!/usr/bin/env python

import gi
gi.require_version('Gtk', '3.0')
gi.require_version('GdkX11', '3.0')
from gi.repository import Gtk
from gi.repository import Gdk
import cairo

def draw_cb(widget, cr):
  width = widget.get_allocated_width()
  height = widget.get_allocated_height()
  context = widget.get_style_context()
  Gtk.render_background(context, cr, 0, 0, width, height)
  cr.set_source_rgba(0,0,0,0.5)
  cr.rectangle(10,10, 100, 100)
  cr.fill()
  return False

window = Gtk.Window()
window.set_default_size(200, 200)
window.connect("destroy", Gtk.main_quit)

textview = Gtk.TextView()
textview.set_wrap_mode(Gtk.WrapMode.WORD_CHAR)
textbuffer = textview.get_buffer()
textbuffer.set_text("Hello world"*18, -1)
textview.connect('draw', draw_cb)
textview.queue_draw()

window.add(textview)
window.show_all()

Gtk.main()