Vue with checkBox

HTML

<script src="https://vuejs.org/js/vue.min.js"></script>
<div id="demo">
  <div v-for="category in categories">
    <input type="checkbox" v-model="item.category" :id="'category_' + category.id" :value="category.id"  />
    <!-- <label>{{ item.category }} : {{ category.id }}</label> -->
  </div>
</div>

JavaScript

var demo = new Vue({
  el: '#demo',
  data() {
    return {
      categories: [{
        "id": 2,
        "name": "news Category 0"
      }, {
        "id": 7,
        "name": "news Category 1"
      }, {
        "id": 1,
        "name": "news Category 2"
      }, {
        "id": 17,
        "name": "news Category 3"
      }, {
        "id": 22,
        "name": "news Category 4"
      }, {
        "id": 27,
        "name": "news Category 5"
      }, {
        "id": 32,
        "name": "news Category 6"
      }, {
        "id": 37,
        "name": "news Category 7"
      }, {
        "id": 42,
        "name": "news Category 8"
      }, {
        "id": 47,
        "name": "news Category 9"
      }, {
        "id": 52,
        "name": "news Category 0"
      }, {
        "id": 57,
        "name": "news Category 1"
      }, {
        "id": 62,
        "name": "news Category 2"
      }, {
        "id": 67,
        "name": "news Category 3"
      }, {
        "id": 72,
        "name": "news Category 4"
      }, {
        "id": 77,
        "name": "news Category 5"
      }, {
        "id": 82,
        "name": "news Category 6"
      }, {
        "id": 87,
        "name": "news Category 7"
      }, {
        "id": 92,
        "name": "news Category 8"
      }, {
        "id": 97,
        "name": "news Category 9"
      }],
      item: {
        category: [1]
      }
    };
  }
})