vue中v-model绑定计算属性值

<template>
        <el-radio-group v-model="planLevel">
          <el-radio-button
            v-for="item in planTypeList"
            :label="item.label"   // 1, 2, 3, 4
            :key="item.label"
          >
            {{ item.name }} 
          </el-radio-button>
        </el-radio-group>
</template>
// 全局参数
import SAFTY_DATA_BASE, { SET_PLANID, SET_PLANLEVEL } from './../data-base'
export default {
  computed: {
    planLevel:  {
      get: () => { return SAFTY_DATA_BASE.planLevel },
      set: (value) => SET_PLANLEVEL(value)
    }
  }
}

//data-base.js
const SAFTY_DATA_BASE = Vue.observable({
  planLevel: 4,
})

const SET_PLANLEVEL = (planLevel) => {
  SAFTY_DATA_BASE.planLevel = planLevel
}

export {
  SET_PLANLEVEL
}
export default SAFTY_DATA_BASE