[pygtk] gtk.DrawingArea mouse move event

[Luigi Paioro]

Hi to all!

I'm new to PyGTK development, so excuse me if the question is naive.

I'd like to write a canvas area with two lines (one vertical and the 
other horizontal) that draw my mouse pointer as a "target" on a 
gtk.DrawingArea. This is my code:


###########

import pygtk
pygtk.require('2.0')
import gtk
import operator
import time
import string

class DrawingAreaExample:
     def __init__(self):

         window = gtk.Window(gtk.WINDOW_TOPLEVEL)
         window.set_title("Drawing Area Example")
         window.connect("destroy", lambda w: gtk.main_quit())
         self.area = gtk.DrawingArea()
         self.pangolayout = self.area.create_pango_layout("")
         self.area.set_size_request(400, 300)
         self.area.set_events(gtk.gdk.POINTER_MOTION_MASK |
                              gtk.gdk.POINTER_MOTION_HINT_MASK )
         self.area.connect("motion_notify_event", self.draw_cursor)
         self.area.connect("expose-event", self.area_expose_cb)
         window.add(self.area)
         self.area.show()
         window.show()

     def draw_cursor(self, area, event):
         area.window.draw_line(self.gc, 0, event.y, 400, event.y)
         area.window.draw_line(self.gc, event.x, 0, event.x, 300)


     def area_expose_cb(self, area, event):
         self.style = self.area.get_style()
         self.gc = self.style.fg_gc[gtk.STATE_NORMAL]

def main():
     gtk.main()
     return 0

if __name__ == "__main__":
     DrawingAreaExample()
     main()

###########


The problem is that the pointer doesn't follow the mouse unless I click 
with the mouse. Moreover I have to delete the previous lines too...

How can I do?


Thanks a lot.

Luigi