Add tab

def add_tab(self, widget, name, filename=''):
        """Add tab"""
        self.clients.append(widget)
        index = self.tabwidget.addTab(widget, name)
        self.filenames.insert(index, filename)
        self.tabwidget.setCurrentIndex(index)
        if self.dockwidget and not self.main.is_setting_up:
            self.switch_to_plugin()
        self.activateWindow()
        widget.get_control().setFocus()
        self.update_tabs_text()