def draw(self, cr):
        self.bounds = self.area.get_allocation()

        # Draw background.
        cr.set_source_rgb(0.915, 0.915, 1)
        cr.rectangle(0, 0, self.bounds.width, self.bounds.height)
        cr.fill()

        # Draw the balloons.
        for b in self.balloons:
            self.draw_balloon(cr, b)

        if self.finished:
            self.draw_results(cr)
        else:
            self.draw_instructions(cr)

            self.draw_score(cr)