binding to the frame or the specific instance?

wxPython Users
1

Ok, confused again with this example. From my understanding,
non-CommandEvent events must be bound to the instance itself, not to
the frame. But when I do this:

self.timer.Bind(wx.EVT_TIMER, self.OnTimer)

instead of:

self.Bind(wx.EVT_TIMER, self.OnTimer, self.timer)

it doesn't work. So why does binding to the frame work in this case
and the other way doesn't work?

Thanks,
John

···

On 7/21/06, John Salerno <johnjsal@gmail.com> wrote:

> ---------- Forwarded message ----------
> From: Robin Dunn <robin@alldunn.com>
> To: wxPython-users@lists.wxwidgets.org
> Date: Thu, 20 Jul 2006 17:34:12 -0700
> Subject: Re: [wxPython-users] binding to the frame or the specific instance?
> John Salerno wrote:
> > Can someone explain to me the difference between these two ways of
> > binding a click event:
> >
> > self.Bind(wx.EVT_BUTTON, self.OnClick, self.button)
> >
> > and
> >
> > self.button.Bind(wx.EVT_BUTTON, self.OnClick)
> >
> > Both seem to work, so I assume in some cases it doesn't matter which
> > you use. Did I just get lucky here, or can buttons be done either way?
>
> http://wiki.wxpython.org/index.cgi/self.Bind_vs._self.button.Bind
>
> Yes, I was in a *very* metaphoric mood today. :wink:
>
> --
> Robin Dunn
> Software Craftsman
> http://wxPython.org Java give you jitters? Relax with wxPython!

Thanks very much, that was a big help! I read it in your book already,
but somehow that helped to solidify it a little more. It seems to make
more sense to me to always use self.widget.Bind instead of just
self.Bind, but as you know, there are possible repercussions to this.

2

John Salerno wrote:

Ok, confused again with this example. From my understanding,
non-CommandEvent events must be bound to the instance itself, not to
the frame. But when I do this:

self.timer.Bind(wx.EVT_TIMER, self.OnTimer)

instead of:

self.Bind(wx.EVT_TIMER, self.OnTimer, self.timer)

it doesn't work. So why does binding to the frame work in this case
and the other way doesn't work?

Because for every rule there is an exception. :wink: Timers don't deliver the events to themselves[*], but to the window that was passed to the wx.Timer constructor or the SetOwner method.

[*] Actually in a way they do if there is no owner set, but instead of processing the event normally they call the Notify method of a derived class. This is done for backwards compatibility with how the timers used to work before they were taught how to send events to windows.

···

--
Robin Dunn
Software Craftsman
http://wxPython.org Java give you jitters? Relax with wxPython!