VUE使用v-for循环不刷新视图的问题，求教

Question

为什么_this.divFormList[0] = divFormListArr不刷新视图

_this.divFormList = divFormListArr可以刷新视图

代码如下

<template>
  <div class="form-container">
    <div class="btn-container">
      <el-button type="primary">添加表格</el-button>
    </div>
    <div
            v-for="(itemDiv, indexDiv) in divFormList"
            :key="'divForm' + indexDiv"
            :class="{ 'div-form-container':true, 'mt10':false}"
    >
      <div class='form-delete-container'>
        <el-button
                icon='el-icon-delete'
                size='small'
        >
        </el-button>
      </div>
      <el-form
              style="margin-top: 5px"
              :label-position="labelPosition"
              ref="form"
              :model="form"
              label-width="80px">
        <el-row
                v-for="(itemRow, indexRow) in itemDiv"
                :key="'row' + indexRow"
        >
          <el-col :span="12" v-for="(item, index) in itemRow" >
            <el-form-item
                    :label="item.description"
                    :key="index"
                    style="box-sizing: border-box;padding-right: 5px"
            >
              <el-input v-model="item.name" size="small"></el-input>
            </el-form-item>
          </el-col>
        </el-row>
      </el-form>
    </div>

  </div>
</template>

<script>
export default {
  name: "formOperation",
  data() {
    return {
      form: {
        name: '',
        region: '',
        date1: '',
        date2: '',
        delivery: false,
        type: [],
        resource: '',
        desc: ''
      },
      divFormList: [ // divFormList
          [ // itemDiv
            [ // itemRow
              {
                "columnAttrList": [],
                "showType": "input",
                "attrList": [],
                "sysEventList": [],
                "sysRule": {},
                "dataSourceType": null,
                "dataSource": null,
                "name": "zhuanye",
                "model": "field_1611043120000_63863",
                "type": "field",
                "icon": "icon-input",
                "key": "1611043120000_63863",
                "width": "100%",
                "defaultValue": null,
                "attrObject": {},
                "sysAttrList": [],
                "eventList": [],
                "description": "专业123",
                "componentType": "文本输入框"
              },
              {
                label: "活动名称2",
                name: "",
                description: "活动描述2"
              }
            ],
            [
              {
                label: "活动名称3",
                name: "",
                description: "活动描述3"
              },
              {
                label: "活动名称4",
                name: "",
                description: "活动描述4"
              }
            ],
            [
              {
                label: "活动名称5",
                name: "",
                description: "活动描述5"
              }
            ]
          ]
      ],
      divFormStyle: true,
      mt10: true,
      sysGridFieldList: [
        {
          "columnAttrList": [],
          "showType": "input",
          "attrList": [],
          "sysEventList": [],
          "sysRule": {},
          "dataSourceType": null,
          "dataSource": null,
          "name": "zhuanye",
          "model": "field_1611043120000_63863",
          "type": "field",
          "icon": "icon-input",
          "key": "1611043120000_63863",
          "width": "100%",
          "defaultValue": null,
          "attrObject": {},
          "sysAttrList": [],
          "eventList": [],
          "description": "专业",
          "componentType": "文本输入框"
        },
        {
          "columnAttrList": [],
          "showType": "input",
          "attrList": [],
          "sysEventList": [],
          "sysRule": {},
          "dataSourceType": null,
          "dataSource": null,
          "name": "schoolName",
          "model": "field_1611043120000_64114",
          "type": "field",
          "icon": "icon-input",
          "key": "1611043120000_64114",
          "width": "100%",
          "defaultValue": null,
          "attrObject": {},
          "sysAttrList": [],
          "eventList": [],
          "description": "学校名称",
          "componentType": "文本输入框"
        },
        {
          "columnAttrList": [],
          "showType": "input",
          "attrList": [],
          "sysEventList": [],
          "sysRule": {},
          "dataSourceType": null,
          "dataSource": null,
          "name": "beginTime",
          "model": "field_1611043120000_80485",
          "type": "field",
          "icon": "icon-input",
          "key": "1611043120000_80485",
          "width": "100%",
          "defaultValue": null,
          "attrObject": {},
          "sysAttrList": [],
          "eventList": [],
          "description": "入学时间",
          "componentType": "文本输入框"
        },
        {
          "columnAttrList": [],
          "showType": "input",
          "attrList": [],
          "sysEventList": [],
          "sysRule": {},
          "dataSourceType": null,
          "dataSource": null,
          "name": "staffId",
          "model": "field_1611043120000_39791",
          "type": "field",
          "icon": "icon-input",
          "key": "1611043120000_39791",
          "width": "100%",
          "defaultValue": null,
          "attrObject": {},
          "sysAttrList": [],
          "eventList": [],
          "description": "staff_主键",
          "componentType": "文本输入框"
        },
        {
          "columnAttrList": [],
          "showType": "input",
          "attrList": [],
          "sysEventList": [],
          "sysRule": {},
          "dataSourceType": null,
          "dataSource": null,
          "name": "endTime",
          "model": "field_1611043120000_91797",
          "type": "field",
          "icon": "icon-input",
          "key": "1611043120000_91797",
          "width": "100%",
          "defaultValue": null,
          "attrObject": {},
          "sysAttrList": [],
          "eventList": [],
          "description": "毕业时间",
          "componentType": "文本输入框"
        }
      ],
      labelPosition: 'right'
    }
  },
  mounted () {
    const _this = this
    this.$nextTick(()=>{
      let divFormListArr = []
      divFormListArr.push(_this.handleArrayByColumn(_this.sysGridFieldList, 2))
      console.log('divFormListItem == ', divFormListArr)
      _this.divFormList[0] = divFormListArr
      // _this.divFormList = divFormListArr
    })
    // console.log(_this.divFormList)
  },
  methods: {
    onSubmit() {
      console.log('submit!');
    },
    addFormItem () {

    },
    handleArrayByColumn (data, num) {
      if(Array.isArray(data)) {
        let rowNum = Math.ceil(data.length/num)
        console.log('is array == ', rowNum)
        let itemDiv = []
        for(let x=0; x<rowNum; x++) {
          let rowArr = []
          for(let y=0+(x*num); y<num+(x*num); y++) {
            if(data[y] !== undefined) {
              rowArr.push(data[y])
            }
          }
          itemDiv[x] = rowArr
        }
        console.log('itemDiv == ', itemDiv)
        return itemDiv
      } else {
        // console.log('is not array')
      }
    }
  }
}
</script>

<style lang="scss" scoped>
  .form-container {
    padding: 20px;
  }
  .div-form-container {
    /*background: fuchsia;*/
  }
  .form-delete-container {
    width: 80px;
    text-align: right;
    vertical-align: middle;

    font-size: 14px;
    color: #606266;
    line-height: 40px;
    padding: 0 12px 0 0;
    -webkit-box-sizing: border-box;
    box-sizing: border-box;
  }
  .mt10 {
    margin-top: 10px;
    background: fuchsia;
  }
</style>

Answer 1