[pygtk] CheckButton & signals

[Alessandro Dentella]

Hi, rereading myself I see I can improve the explanation.

While trying to implement the tri-state checkbutton I stumbled across some
problems that I think should be trivial. 

I added to a check butto a callback to get into inconsistent state (and it
works) but a subsequent click triggers the function that toggles it
again. So I only loop trhought True/inconsistent

So I wanted to stop the native togggling and was not able. And this is poit
1 below:

---- previuous essage  ----------

  i think my problem is very simple but I didn't get it right...
  All I want to do is substitute normal toggling of CheckButton to step into
  inconsisten mode. I have the working situation in a CellRenderer but now I
  need it also for normal Widgets.

  1. I thought I'd connect to 'toggled' signal and 'return True'. But that
     seems to not be enought. Isn't that a general rule? After a handler
     returns True, no more processing is done on that signal?

     In the FAQ I see widget.emit_stop_by_name but I was not able to use it
     (and I don't remember I have ever used it)


  2. I thought I got the wrong signal: how should I verify which is the
     correct one (the one that trigges the change of "active" status)?

        c.connect('toggled', lambda  b: True)
        c.connect('clicked', lambda  b: True)
     
     still toggles Between active on/off  

  3. tere is a difference if I use set_active(is_active) or if I set
     directly the value: button.active = is_active.

     In the first case the example below loops into inconsistent/consistent
     In the second it loops throught active/inactive


thaks in advance for any help
sandro
*:-)



here is the test I used:


import gtk


class MyCheck(object):
    
    def __init__(self):
        w = gtk.Window()
        h = gtk.VBox()
        w.add(h)
        b = gtk.Button('reset')
        c1 = gtk.CheckButton('toggle and clecked -> True')
        c2 = gtk.CheckButton('toggle with null')
        h.add(b)
        h.add(c1)
        h.add(c2)
        b.connect('clicked', self.butt_cb)

        c1.connect('toggled', lambda  b: True)
        c1.connect('clicked', lambda  b: True)

        c2.connect('clicked', self.toggle_with_null_cb)
        self.c2 = c2
        w.show_all()

    def toggle_with_null_cb(self, button):
        """a toggle function that loops through inconsinstent state also
        """
        value = button.get_active()
        null = button.get_inconsistent()

        ## -   -> True  -> False
        if null:  # - next is True
            print "turn to True"
            button.set_active(True)
            button.set_inconsistent(False)
        else:
            if value == True:
                print "turn to False"
                button.set_inconsistent(False)
                button.set_active(False)
            else:
                print "turn to Null"
                button.set_inconsistent(True)

        return True

    def butt_cb(self, *args):
        self.c2.set_inconsistent(False)
        self.c2.set_active(False)
            
if __name__ == '__main__':
    m = MyCheck()
    try:
        gtk.main()
    except KeyboardInterrupt:
        import sys
        sys.exit()