在index.js页面中设置路由跳转中加上meta，然后利用vue的beforeEach遍历设置每个页面的title
亲测有效

const router=new Router({
  routes: [
    {
      path: '/',
      name: 'goods',
      component: goods,
      meta: {
        title: '首页入口'
      }
    },{
        path:'/ratings',
        name:'ratings',
        component:ratings,
        meta: {
        title: '评论'
      }
    },{
        path:'/seller',
        name:'seller',
        component:seller,
        meta: {
        title: '售卖'
      }
    }
  ]
})

router.beforeEach((to,form,next) =>{
    /*路由变化修改title*/
    if(to.meta.title){
        document.title=to.meta.title
    }
    next();
})
export default router