//父组件，引用component-tag-name
<component-tag-name bind:myevent="onMyEvent" />

//index.js
Component({
    onMyEvent(e) {
        e.detail.count // 自定义组件触发事件时提供的detail对象，结果为1
    }
})

//子组件
<button bindtap="onTap">点击这个按钮将触发“myevent”事件</button>

//index.js
Component({
  properties: {},
  methods: {
    onTap() {
      const myEventDetail = {count:1} // detail对象，提供给事件监听函数
      const myEventOption = {} // 触发事件的选项
      this.triggerEvent('myevent', myEventDetail, myEventOption)
    }
  }
})