vue中 evenBus调用,兄弟间传值

main.js中----------
new Vue({
    router,
    store,
    data: {
        eventHub: new Vue()
    },
    render: h => h(App),
    watch: {
        '$route.path': function(newVal, oldVal) {
            const userId = this.$route.query.userId || localStorage.getItem('userIds');
            const parkId = this.$route.query.id || localStorage.getItem('parkId');
            this.$router.push({ query: { id: parkId, userId: userId } });
            localStorage.setItem('userIds', userId);
            localStorage.setItem('parkId', parkId);
        }
    }
}).$mount("#app");

this.$root.eventHub.$on("controlbgChange", (res) => {
       console.log('res',res)
      });

this.$root.eventHub.$emit("controlbgChange", path);