old_contents: #!/usr/bin/env python
  import gtk
  
  from kiwi.controllers import BaseController
  from kiwi.ui.views import BaseView
  from kiwi.ui.gadgets import quit_if_last
  
  class FarenControl(BaseController):
  
      def on_quitbutton__clicked(self, *args):
          self.view.hide_and_quit()
  
      def after_temperature__changed(self, entry, *args):
          try:
              temp = float(entry.get_text())
          except ValueError:
              temp = 0
          celsius = (temp - 32) * 5/9.0
          farenheit = (temp * 9/5.0) + 32
          self.view.celsius.set_text("%.2f" % celsius)
          self.view.farenheit.set_text("%.2f" % farenheit)
  
  widgets = ["quitbutton", "temperature", "celsius", "farenheit"]
  view = BaseView(gladefile="faren", delete_handler=quit_if_last,
                  widgets=widgets)
  ctl = FarenControl(view)
  view.show()
  gtk.main()
  
new_contents: #!/usr/bin/env python
  import gtk
  
  from kiwi.controllers import BaseController
  from kiwi.ui.views import BaseView
  from kiwi.ui.gadgets import quit_if_last
  
  class FarenControl(BaseController):
  
      def on_quitbutton__clicked(self, *args):
          self.view.hide_and_quit()
  
      def after_temperature__insert_text(self, entry, *args):
          try:
              temp = float(entry.get_text())
          except ValueError:
              temp = 0
          celsius = (temp - 32) * 5/9.0
          farenheit = (temp * 9/5.0) + 32
          self.view.celsius.set_text("%.2f" % celsius)
          self.view.farenheit.set_text("%.2f" % farenheit)
  
  widgets = ["quitbutton", "temperature", "celsius", "farenheit"]
  view = BaseView(gladefile="faren", delete_handler=quit_if_last,
                  widgets=widgets)
  ctl = FarenControl(view)
  view.show()
  gtk.main()
  
subject: Use insert_text instead of changed