docs: def _do_connection(self, wgt, sig, func):
          """
          Make a connection between a GUI widget and a callable.
  
          wgt and sig are strings with widget and signal name
          func is a callable for that signal
          """
          #new style  (we use this)
          #self.btn_name.clicked.connect(self.on_btn_name_clicked)
          #old style
          #self.connect(self.btn_name, SIGNAL('clicked()'), self.on_btn_name_clicked)
  
          if hasattr(self, wgt):
              wgtobj = getattr(self, wgt)
              if hasattr(wgtobj, sig):
                  sigobj = getattr(wgtobj, sig)
                  if isinstance(sigobj, Signal):
                      sigobj.connect(func)
                      return 0
          return 1