如何在 Vue.js 中使用 v-for 动态创建一个新的 div？

Question

I want to create div's dynamically based on the number of elements present in an array. The div's contain the html element created by ProgressBar.js.

This the Vue.js code

 import ProgressBar from 'progressbar.js' var bar; export default { data() { return { fitness: ['Run', 'Cycle'], val: 0.65 } }, mounted(){ this.showProgressBar(this.val); }, created: function() { }, methods:{ showProgressBar: function(val){ new ProgressBar.Circle('#container',{ trailColor: 'gainsboro', trailWidth: 20, color: 'teal', strokeWidth: 20 }).animate(val); } } }

 <div class="content" v-for="fitness in fitness"> <span>{{ fitness }}</span> <div id="container"></div> </div>

Since an id is associated with only one div, I am not able to execute a new ProgressBar.Circle object that would create another div. Is there a way to dynamically create a new div with different a id inside the v-for every time the new ProgressBar.circle is executed? Can somenone please help me out here?

Answer 1

Here is a re-usable component that wraps progressbar.js .

<template>
  <div class="container"><div ref="bar"></div></div>
</template>
<script>
  import ProgressBar from "progressbar.js"

  export default {
    props:["options", "val"],
    mounted(){
      new ProgressBar.Circle(this.$refs.bar, this.options).animate(this.val)
    } 
  }
</script>
<style>
  .container{
    width:100px; 
    height: 100px
  }
</style>

Here is how it's used in a template:

<div v-for="fit in fitness" class="fitness">
  <div>{{fit.name}}</div>
  <progress-bar :val="fit.val" :options="options"></progress-bar>
</div>

Working Example .

Answer 2

One solution could be give unique ids to each container div and create progress bars for each of them.

Try the code below -

 import ProgressBar from 'progressbar.js' var bar; export default { data() { return { fitness: ['Dietary Intake', 'Exercise'], val: [0.65, 9] } }, mounted() { this.showProgressBar(); }, created: function() { }, methods: { showProgressBar: function() { this.fitness.forEach((f, i) => { new ProgressBar.Circle('#container-' + i, { trailColor: 'gainsboro', trailWidth: 20, color: 'teal', strokeWidth: 20 }).animate(this.val[i]); }); } } }

 <div class="content" v-for="(f, index) in fitness"> <span>{{ f }}</span> <div v-bind:id="`container-${index}`"></div> </div>

Update - val can be an array. And its values can be referenced from the within the showProgressBar function.

I am assuming the length of fitness and val arrays are the same.

Update 2 - Explanation.

So basically there are 2 main issues here that have to addressed.

1. Generating multiple container divs

We need to generate multiple container divs as there are going to be multiple ProgressBars . But we need to distinguish between them so we create a unique id for each of them. That is what the following code does.

<div class="content" v-for="(f, index) in fitness">
  <span>{{ f }}</span>
  <div v-bind:id="`container-${index}`"></div>
</div>

Since index numbers are unique. Adding them to "container" generated unique ids. See List Rendering

2. Generate multiple ProgressBars when component mounts.

This is simpler we simple create new ProgressBar for each "fitness" value.

this.fitness.forEach((f, i) => {
  new ProgressBar.Circle('#container-' + i, {
    trailColor: 'gainsboro',
    trailWidth: 20,
    color: 'teal',
    strokeWidth: 20
  }).animate(this.val[i]);

Refer - Array forEach