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<!-- item template -->
<script type="text/x-template" id="item-template">
  <div v-class="bold: isFolder"
    v-on="click: toggle, dblclick: changeType">
    {{model.name}}
    <span v-if="isFolder">[{{open ? '-' : '+'}}]</span>
  </div>
  <ul v-show="open" v-if="isFolder">
    <li class="item"
      v-repeat="model: model.children"
      v-component="item">
    </li>
    <li v-on="click: addChild">+</li>
  </ul>
</script>

<p>(You can double click on an item to turn it into a folder.)</p>

<!-- the demo root element -->
<ul id="demo">
  <li class="item"
    v-component="item"
    v-with="model: treeData">
  </li>
</ul>

// demo data
var data = {
  name: 'My Tree',
  children: [
    { name: 'hello' },
    { name: 'wat' },
    {
      name: 'child folder',
      children: [
        {
          name: 'child folder',
          children: [
            { name: 'hello' },
            { name: 'wat' }
          ]
        },
        { name: 'hello' },
        { name: 'wat' },
        {
          name: 'child folder',
          children: [
            { name: 'hello' },
            { name: 'wat' }
          ]
        }
      ]
    }
  ]
}

// define the item component
Vue.component('item', {
  template: '#item-template',
  data: function () {
    return {
      open: false
    }
  },
  computed: {
    isFolder: function () {
      return this.model.children &&
        this.model.children.length
    }
  },
  methods: {
    toggle: function () {
      if (this.isFolder) {
        this.open = !this.open
      }
    },
    changeType: function () {
      if (!this.isFolder) {
        this.model.$add('children', [])
        this.addChild()
        this.open = true
      }
    },
    addChild: function () {
      this.model.children.push({
        name: 'new stuff'
      })
    }
  }
})

// boot up the demo
var demo = new Vue({
  el: '#demo',
  data: {
    treeData: data
  }
})

body {
  font-family: Menlo, Consolas, monospace;
  color: #444;
}
.item {
  cursor: pointer;
}
.bold {
  font-weight: bold;
}
ul {
  padding-left: 1em;
  line-height: 1.5em;
  list-style-type: dot;
}