Total lines in a GCode file

    def on_hal_status_file_loaded(self, widget, filename):
        widgetlist = ["btn_use_current" ]
        # this test is only necessary, because of remap and toolchange, it will emit a file loaded signal
        if filename:
            fileobject = open(filename, 'r')
            lines = fileobject.readlines()
            fileobject.close()
            self.halcomp["program.length"] = len(lines)

            if len(filename) > 70:
                filename = filename[0:10] + "..." + filename[len(filename) - 50:len(filename)]
            self.widgets.lbl_program.set_text(filename)
            self._sensitize_widgets(widgetlist, True)
        else:
            self.halcomp["program.length"] = 0
            self._sensitize_widgets(widgetlist, False)
            self.widgets.lbl_program.set_text(_("No file loaded"))