vant-weapp/packages/grid/index.ts

import { VantComponent } from '../common/component';

VantComponent({
  relation: {
    name: 'grid-item',
    type: 'descendant',
    linked(child) {
      this.children.push(child);
    },
    unlinked(child) {
      this.children = this.children.filter(
        (item: WechatMiniprogram.Component.TrivialInstance) => item !== child
      );
    }
  },

  props: {
    square: {
      type: Boolean,
      observer: 'updateChildren'
    },
    gutter: {
      type: [Number, String],
      value: 0,
      observer: 'updateChildren'
    },
    clickable: {
      type: Boolean,
      observer: 'updateChildren'
    },
    columnNum: {
      type: Number,
      value: 4,
      observer: 'updateChildren'
    },
    center: {
      type: Boolean,
      value: true,
      observer: 'updateChildren'
    },
    border: {
      type: Boolean,
      value: true,
      observer: 'updateChildren'
    }
  },

  beforeCreate() {
    this.children = [];
  },

  created() {
    const { gutter } = this.data;
    if (gutter) {
      this.setData({
        style: `padding-left: ${gutter}px`
      });
    }
  },

  methods: {
    updateChildren() {
      this.children.forEach(
        (child: WechatMiniprogram.Component.TrivialInstance) => {
          child.updateStyle();
        }
      );
    }
  }
});