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<div id="el"></div>

<!-- using string template here to work around HTML <option> placement restriction -->
<script type="text/x-template" id="demo-template">
  <div>
    <p>Selected: {{ selected }}</p>
    <select2 :options="options" v-model="selected">
      <option disabled value="0">Select one</option>
    </select2>
  </div>
</script>

<script type="text/x-template" id="select2-template">
  <select>
    <slot></slot>
  </select>
</script>
Vue.component('select2', {
  props: ['options', 'value'],
  template: '#select2-template',
  mounted: function () {
    var vm = this
    $(this.$el)
      .val(this.value)
      // init select2
      .select2({ data: this.options })
      // emit event on change.
      .on('change', function () {
        vm.$emit('input', this.value)
      })
  },
  watch: {
    value: function (value) {
      // update value
      $(this.$el).val(value)
    },
    options: function (options) {
      // update options
      $(this.$el).select2({ data: options })
    }
  },
  destroyed: function () {
    $(this.$el).off().select2('destroy')
  }
})

var vm = new Vue({
  el: '#el',
  template: '#demo-template',
  data: {
    selected: 0,
    options: [
      { id: 1, text: 'Hello' },
      { id: 2, text: 'World' }
    ]
  }
})
html, body {
  font: 13px/18px sans-serif;
}
select {
  min-width: 300px;
}