npm install vue-contextmenujs -S || yarn add vue-contextmenujs

mounted() {
    this.visible = true;
    for (let item of this.items) {
      if (item.icon) {
        this.hasIcon = true;
        break;
      }
    }
    /**
     * 修復(fù)超出溢出的問題
     */
    this.$nextTick(() => {
      const windowWidth = document.documentElement.clientWidth;
      const windowHeight = document.documentElement.clientHeight;
      const menu = this.$refs.menu;
      const menuWidth = menu.offsetWidth;
      const menuHeight = menu.offsetHeight;

      (this.openTrend === SUBMENU_OPEN_TREND_LEFT
        ? this.leftOpen
        : this.rightOpen)(windowWidth, windowHeight, menuWidth);
      this.style.top = this.position.y;
      if (this.position.y + menuHeight > windowHeight) {
        if (this.position.height === 0) {
           let diffVal = this.position.y + menuHeight - windowHeight;
           this.style.top = this.position.y - diffVal;
           if(this.position.y<windowHeight/2){//點擊的是上半屏
             if(this.position.y>menuHeight){
               this.style.top = this.position.y;
             }
           }else{//點擊的是下半屏
              if(this.position.y>menuHeight){
               this.style.top = this.position.y-menuHeight;
             }
           }
        } else {
          this.style.top = windowHeight - menuHeight;
        }
      }
    });
  },

import Contextmenu from '@/components/global/vue-contextmenujs';
Vue.use(Contextmenu);