try mobx

so want to use vue to mpvue directly

if there are no restrictions on the base library, there is an official computed component extension : https://github.com/wechat-min...
the following code is excerpted from the official website:

const computedBehavior = require('miniprogram-computed')

Component({
  behaviors: [computedBehavior],
  data: {
    a: 0,
  },
  computed: {
    b() {
      //  data  setData 
      //  this.data.b 
      return this.data.a + 100
    },
  },
  methods: {
    onTap() {
      this.setData({
        a: PPthis.data.a,
      })
    }
  }
})