update stat regarding to file operation,
            e.g. open, save, saveas, etc.

def _file_stat(self, mode, infostr, stat):
        """ update stat regarding to file operation,
            e.g. open, save, saveas, etc.
        """
        action_str = mode.upper()
        info_str = infostr

        if stat == 'OK':
            self.action_st_panel.SetBackgroundColour('#00FF00')
        else:  # ERR
            self.action_st_panel.SetBackgroundColour('#FF0000')
        self.action_st.SetLabel(action_str)
        if info_str is None:
            info_str = 'Undefined File'
        self.info_st.SetLabel(info_str)
        if self.info_st.IsEllipsized():
            self.info_st.SetToolTip(wx.ToolTip(info_str))

        self.log.append({'stat': stat,
                         'logstr':
                             "[{ts}] {acts:<10s} : {infs}".format(ts=time.strftime(
                                 "%Y/%m/%d-%H:%M:%S", time.localtime()),
                                 acts=action_str,
                                 infs=info_str)})