Python: how to switch between workspaces using Xlib?

How do I switch between my window manager's workspaces using Python with Xlib module?

This is my most promising attempt:

#!/usr/bin/python

from Xlib import X, display, error, Xatom, Xutil
import Xlib.protocol.event

screen = Xlib.display.Display().screen()
root   = screen.root


def sendEvent(win, ctype, data, mask=None):
        """ Send a ClientMessage event to the root """
        data = (data+[0]*(5-len(data)))[:5]
        ev = Xlib.protocol.event.ClientMessage(window=win, client_type=ctype, data=(32,(data)))

        if not mask:
            mask = (X.SubstructureRedirectMask|X.SubstructureNotifyMask)
        root.send_event(ev, event_mask=mask)


# switch to desktop 2
sendEvent(root, Xlib.display.Display().intern_atom("_NET_CURRENT_DESKTOP"), [2])

The above code is shamelessly stolen from various places in the PyPanel source; unfortunately, it doesn't do anything, not even generate a warning / exception. Am I missing something here?

I'm using Python and PyGTK. Xlib seems to be the right choice for switching desk开发者_JAVA技巧tops. I don't intend to use wnck (buggy Python module) or similar, but I'd appreciate any pointers anyway.

I might add that this is my first attempt at writing a Python application using Xlib (or PyGTK).

Apparently you need to work on the same Display object and then flush it at the end. Something like:

display = Xlib.display.Display()
screen = display.screen()
root = screen.root

# ...

sendEvent(root, display.intern_atom("_NET_CURRENT_DESKTOP"), [1, X.CurrentTime])
display.flush()

Credit: Idea from a very similar thread (which almost works).

P.S. By the way, the desktop number starts from 0.