like the following code, how can I get form.datefrom in onClick.
my original requirement is to have a shortcut to implement the date of the form.datefrom+1 year

data() {
    return {
      form: { tenants: [], datefrom: new Date() },
      loading: false,
      daterangeOptions: {
        disabledDate: (time) => {
          const beginDateVal = this.$moment(this.form.datefrom)
          if (beginDateVal) {
            return this.$moment(time) < beginDateVal
          }
        },
        shortcuts: [{
          text: "",
          onClick(picker) {
            picker.$emit("pick", this.$moment(this.form.datefrom).add(1, "y"))
          }
        }, {
          text: "",
          onClick(picker) {
            picker.$emit("pick", this.$moment(this.form.datefrom).add(6, "M"))
          }
        }, {
          text: "",
          onClick(picker) {
            picker.$emit("pick", this.$moment(this.form.datefrom).add(3, "M"))
          }
        }, {
          text: "",
          onClick: (picker) => {
            debugger
            picker.$emit("pick", this.$moment(this.form.datefrom).add(1, "M"))
          }
        }]
      }
    }
  }