weex跨页面通信

需求：

A页面有表单和表格，点击表格中的按钮到B页面，B页面操作完毕，再次回到A页面，表单元素保持不变，表格内容刷新。

通过管道通信去做，用两个管道嵌套，A页面跳转到B页面的时候，直接用管道发过去，B页面收不到信息，需要B页面先告诉A页面可以传值了，A页面再传值。B页面再接收A页面传过来的值，操作页面完成后，再将数据通过另一个管道传回去。

A页面：

const fatherOK = new BroadcastChannel('fatherOK')
const fatherFormData = new BroadcastChannel('fatherFormData')

mounted() {
    this.$next(() => {
      fatherOK.onmessage = (e) => {
        if (e.data.message == 'OK') {
          fatherFormData.postMessage({ fatherData: this.infoForm })
        }
      },
        fatherFormData.onmessage = (e) => {
          if (e.data.fatherData) {
            let fatherInfoForm = e.data.fatherData
            if (fatherInfoForm) {
              Object.assign(this.infoForm, fatherInfoForm)
              this.handleSearch();
            }
          }
        }
    }
}

B页面：

const fatherOK = new BroadcastChannel('fatherOK')
const fatherFormData = new BroadcastChannel('fatherFormData')

mounted() {
    this.$next(() => {
        fatherFormData.onmessage = (e) => {
          this.fatherData = e.data.fatherData;
        },
        fatherOK.postMessage({message:"OK"});
    }
}
给A页面的传值：

fatherFormData.postMessage({fatherData: this.fatherData})