wxPython validators not working as expected

Question

I've written a dialog in wxPtyhon with two comboboxes to which I've attached a custom validator, the purpose being to insure that, if a value is typed, it is an numeric string. Problem is, the validators aren't being invoked. What am I doing wrong?

    import wx

    # my custom validator class

    class NumericObjectValidator(wx.Validator):
       def __init__(self):
          wx.Validator.__init__(self)

       def Clone(self):
          return NumericObjectValidator()

       # Why isn't this method being called when the user types in the CB field?
       def Validate(self, win):
          cbCtrl = self.GetWindow()
          text = cbCtrl.GetValue()
          print 'control value=',text
          return True

    class SizeDialog(wx.Dialog):
       def __init__(self, parent):
          wx.Dialog.__init__(self, parent, -1, 'Select Size', size=(200,135))

          panel = wx.Panel(self, -1, size=self.GetClientSize())

          sizes = map(str, range(3,21))
          wx.StaticText(panel, -1, 'Rows:', pos=(10, 15))
          self.rows = wx.ComboBox(panel, -1, value='8', choices=sizes,
             style=wx.CB_DROPDOWN, pos=(80,15), validator=NumericObjectValidator())

          wx.StaticText(panel, -1, 'Columns:', pos=(10,40))
          self.cols = wx.ComboBox(panel, -1, choices=sizes, style=wx.CB_DROPDOWN,
             pos=(80,40), value='8', validator=NumericObjectValidator())

          cancel = wx.Button(panel,wx.ID_CANCEL,'Cancel', pos=(20,75))
          wx.Button(panel,wx.ID_OK,'OK', pos=(100,75)).SetDefault()

       def TransferToWindow(self):
          return True

       def TransferFromWindow(self):
          return True

       def get_size(self):
          r = int(self.rows.GetValue())
          c = int(self.cols.GetValue())
          return (c,r)

    if __name__ == "__main__":
       app = wx.App(0)
       dlg = SizeDialog(None)
       dlg.ShowModal()
       dlg.Destroy()

Answer 1

I have no idea why, but copying the wxPython demo works okay.

import wx
import string

# my custom validator class

class NumericObjectValidator(wx.PyValidator):
    def __init__(self):
        wx.PyValidator.__init__(self)
        self.Bind(wx.EVT_CHAR, self.OnChar)

    def Clone(self):
        return NumericObjectValidator()

    def Validate(self, win):
        tc = self.GetWindow()
        val = tc.GetValue()

        for x in val:
            if x not in string.digits:
                return False

        return True


    def OnChar(self, event):
        key = event.GetKeyCode()

        if key < wx.WXK_SPACE or key == wx.WXK_DELETE or key > 255:
            event.Skip()
            return

        if chr(key) in string.digits:
            event.Skip()

        return


class SizeDialog(wx.Dialog):
   def __init__(self, parent):
      wx.Dialog.__init__(self, parent, -1, 'Select Size', size=(200,135))

      panel = wx.Panel(self, -1, size=self.GetClientSize())

      sizes = map(str, range(3,21))
      wx.StaticText(panel, -1, 'Rows:', pos=(10, 15))
      self.rows = wx.ComboBox(panel, -1, value='8', choices=sizes,
         style=wx.CB_DROPDOWN, pos=(80,15), validator=NumericObjectValidator())

      wx.StaticText(panel, -1, 'Columns:', pos=(10,40))
      self.cols = wx.ComboBox(panel, -1, style=wx.CB_DROPDOWN, validator=NumericObjectValidator())

      cancel = wx.Button(panel,wx.ID_CANCEL,'Cancel', pos=(20,75))
      wx.Button(panel,wx.ID_OK,'OK', pos=(100,75)).SetDefault()

   def TransferToWindow(self):
      return True

   def TransferFromWindow(self):
      return True

   def get_size(self):
      r = int(self.rows.GetValue())
      c = int(self.cols.GetValue())
      return (c,r)

if __name__ == "__main__":
   app = wx.App(0)
   dlg = SizeDialog(None)
   dlg.ShowModal()
   dlg.Destroy()