How to use the iview.Menu.Item function in iview

import { routes } from "../../router/spider";
import VueAxios from "vue-axios";
import axios from "assets/axios";
import "root/node_modules/iview/dist/styles/iview.css";

// vuex
Vue.use(Vuex);
Vue.use(Router);
Vue.use(VueAxios, axios);

// 按需引入iview组件
import { Table, Timeline, Menu, Icon, Progress, Cascader,
    Button, Form, Input, Message, Dropdown, Spin } from "iview";
import { Row, Col } from "iview/src/components/grid";
Vue.component("Table", Table);
Vue.component("MenuItem", Menu.Item);
Vue.component("Menu", Menu);
Vue.component("Row", Row);
Vue.component("Col", Col);
Vue.component("Icon", Icon);
Vue.component("Button", Button);
Vue.component("TimelineItem", Timeline.Item);
Vue.component("Progress", Progress);
Vue.component("Form", Form);
Vue.component("FormItem", Form.Item);
Vue.component("Input", Input);
Vue.component("Dropdown", Dropdown);
Vue.component("DropdownMenu", Dropdown.Menu);
Vue.component("DropdownItem", Dropdown.Item);
Vue.component("Cascader", Cascader);
Vue.component("Spin", Spin);
Vue.prototype.$Message = Message;

import axios from "assets/axios";
import { routes } from "../../router";
import { stores } from "../../store";
import "root/node_modules/iview/dist/styles/iview.css";

// use router vuex axios
Vue.use(Router);
Vue.use(Vuex);
Vue.use(VueAxios, axios);

// 按需引入iview组件
import { Card, Timeline, Menu, Icon, Progress, Button, Form, Input, Message } from "iview";
import { Row, Col } from "iview/src/components/grid";
Vue.component("Card", Card);
Vue.component("Timeline", Timeline);
Vue.component("MenuItem", Menu.Item);
Vue.component("Menu", Menu);
Vue.component("Row", Row);
Vue.component("Col", Col);
Vue.component("Icon", Icon);
Vue.component("Button", Button);
Vue.component("TimelineItem", Timeline.Item);
Vue.component("Progress", Progress);
Vue.component("Form", Form);
Vue.component("FormItem", Form.Item);
Vue.component("Input", Input);
Vue.component("Message", Message);

// init router and vuex
const router = new Router({
    routes
});

},
    methods: {
      changeMenu (name) {
        this.$emit('on-change', name);
      }
    },
    updated () {
    	//iview 没有提供 关闭菜单方法 下周天放假的时候 自己修改来打包
      this.$nextTick(() => {
      });
    },
    components: {
      'Icon': Icon,
      'IMenu': Menu,
      'ISubmenu': Menu.Sub,
      'IMenuItem': Menu.Item
    },
    mounted() {
    	//console.log(this.$route.name);
    }
  };

testChangeOpenNames () {
      }
    },
    updated () {
      this.$nextTick(() => {
      });
    },
    components: {
    	'Badge': Badge,
      'Tooltip': Tooltip,
      'Icon': Icon,
      'Modal': Modal,
      'IButton': Button,
      'IMenu': Menu,
      'Submenu': Menu.Sub,
      'IMenuItem': Menu.Item,
      'MenuGroup': Menu.Group,
      'Dropdown': Dropdown,
      'DropdownMenu': Dropdown.Menu,
      'DropdownItem': Dropdown.Item,
      'Avatar': Avatar,
      'SideMenu': SideMenu
    },
    mounted() {
    	//console.log(this.$route);
    }
  };