Vue3 encapsulates the magnifying glass effect component of Jingdong product details page

<template>
  <div class="goods-image">
    <!-- Preview large image -->
    <div class="large" v-show="show" :style="[{ backgroundImage: `url(${images[currIndex]})` }, bgPosition]"></div>
    <!-- Product image-->
    <div class="middle">
      <!-- Product image-->
      <img ref="target" :src="images[currIndex]" alt="" />
      <!-- The mouse enters the mask of the image-->
      <div class="layer" v-show="show" :style="[position]"></div>
    </div>
    <!-- Thumbnail -->
    <ul class="small">
      <li v-for="(img, i) in images" :key="img" :class="{ active: i === currIndex }">
        <!-- Move the mouse to the small picture next to the large picture of the product and the large picture will be displayed-->
        <img @mouseenter="currIndex = i" :src="img" alt="" />
      </li>
    </ul>
  </div>
</template>
<script>
import { reactive, ref, watch } from 'vue'
import { useMouseInElement } from '@vueuse/core'
export default {
  name: 'GoodsImage',
  props: {
    images:
      type: Array,
      default: () => []
    }
  },
  setup(props) {
    // Control the display and hiding of the preview image and mask layer const show = ref(false)
    // Control which image is displayed in the product image const currIndex = ref(0)
    // ref gets the DOM element const target = ref(null)
    // Record the coordinate position of the masked semi-transparent image in the product image const position = reactive({
      top: 0,
      left: 0
    })
    // Record the coordinate position of the area covered by the mask layer in the preview image const bgPosition = reactive({
      backgroundPositionX: 0,
      backgroundPositionY: 0
    })
    // The method useMouseInElement provided by the third-party vueuse gets the coordinates of the mouse in a certain area const { elementX, elementY, isOutside } = useMouseInElement(target)
    // The listener monitors the coordinates of the mouse when it enters the product image to manipulate the mask layer and the preview image effect watch([elementX, elementY, isOutside], () => {
      // When isisOutside.value is true, it means the mouse has not entered the target element. When it is false, it means the mouse has entered the target element. // When it is true, the coordinates are not recorded to avoid performance loss if (isOutside.value) {
        // The mask layer and preview image will not be displayed if the mouse does not enter the target element show.value = false
        return
      }
      // When the mouse enters the target element, the mask layer and the preview image are displayed.show.value = true
      // Determine the boundary value based on the size of the mask layer and the size of the product image // The boundary value of left (left, right)
      if (elementX.value < 100) {
        position.left = 0
      } else if (elementX.value > 300) {
        position.left = 200
      } else {
        position.left = elementX.value - 100
      }
      // Boundary values ​​of top (upper and lower)
      if (elementY.value < 100) {
        position.top = 0
      } else if (elementY.value > 300) {
        position.top = 200
      } else {
        position.top = elementY.value - 100
      }
      // The coordinates of the part of the product image covered by the mask layer in the preview image, plus the unit bgPosition.backgroundPositionY = -position.top * 2 + 'px'
      bgPosition.backgroundPositionX = -position.left * 2 + 'px'
      // The mask layer is relative to the coordinates of the upper left corner of the product image, plus the unit position.top += 'px'
      position.left += 'px'
    })
    // Return to the template using return { currIndex, show, target, position, bgPosition }
  }
}
</script>
<style scoped lang="less">
.goods-image {
  width: 480px;
  height: 400px;
  position: relative;
  display: flex;
  z-index: 500;
  .large {
    position: absolute;
    top: 0;
    left: 412px;
    width: 400px;
    height: 400px;
    box-shadow: 0 0 10px rgba(0, 0, 0, 0.1);
    background-repeat: no-repeat;
    background-size: 800px 800px;
    background-color: #f8f8f8;
  }
  .middle {
    width: 400px;
    height: 400px;
    position: relative;
    cursor: move;
    .layer {
      width: 200px;
      height: 200px;
      background: rgba(0, 0, 0, 0.2);
      left: 0;
      top: 0;
      position: absolute;
    }
  }
  .small {
    width: 80px;
    li {
      width: 68px;
      height: 68px;
      margin-left: 12px;
      margin-bottom: 15px;
      cursor: pointer;
      &:hover,
      &.active {
        border: 2px solid @xtxColor;
      }
    }
  }
}
</style>