file-folder.html

<!--
@license
Copyright (c) 2015 Winston Howes. All rights reserved.
This code may only be used under the MIT license found at https://github.com/winhowes/file-tree/blob/master/LICENSE
-->
<link rel="import" href="../polymer/polymer.html">

<!--
An element acting as a folder with other folders inside of it.

Example:

    <file-folder></file-folder>

@demo
-->

<link rel="import" href="../iron-icons/iron-icons.html">

<dom-module id="file-folder">

  <style>
    :host.selected > .thisFolder > .folderTitle{
      background-color: rgba(31, 141, 214, 0.4);
      border: 1px solid rgba(31, 141, 214, 0.7);
      border-radius: 5px;
    }

    .parent.collapsed:before {
      content: '+ ';
      padding: 5px;
    }

    .parent.expanded:before {
      content: '- ';
      padding: 5px;
    }

    .parent, .name {
      cursor: pointer;
    }

    ul {
      margin: 0;
    }

    li {
      list-style-type: none;
    }

    iron-icon {
      cursor: pointer;
      width: 24px;
      height: 24px;
    }

    [hidden] {
      display: none;
    }
  </style>

  <template>
    <div class="thisFolder">
      <div class="folderTitle">
        <span class$="{{_determineClass(data.open, data.children)}}" on-click="toggleChildren">
          <iron-icon icon$="{{_determineIcon(data.shared)}}"></iron-icon>
        </span>
        <span class="name" on-click="selectFolder">{{data.name}}</span>
      </div>
      <ul hidden$={{!data.open}}>
        <template is="dom-repeat" items="{{data.children}}">
          <li>
            <file-folder data="{{item}}"></file-folder>
          </li>
        </template>
      </ul>
    </div>
  </template>

</dom-module>

<script>

  Polymer({

    is: 'file-folder',

    properties: {

      /**
       * `data` is the data to be used for the tree.
       */
      data: {
        type: Object,
        value: function() {
          return {};
        }
      },

    },

    /**
     * The `folderSelected` event is fired whenever `selectFolder` is called.
     *
     * @event folderSelected
     */

    /**
     * Returns the necessary classes.
     *
     * @param {boolean}, whether or not the folder is open
    */
    _determineClass: function(open, children) {
      return 'parent ' + ((open && children && children.length) ? 'expanded' : children && children.length ? 'collapsed' : '');
    },

    /**
     * Returns the necessary folder icon.
     *
     * @param {boolean}, whether or not the folder is shared
    */
    _determineIcon: function(shared) {
      return shared ? 'folder-shared' : 'folder';
    },

    /**
     * Highlights folder as the selected folder.
    */
    selectFolder: function(e) {
      this.fire("folderSelected", this);
    },

    /**
     * Toggles the children nodes on or off.
    */
    toggleChildren: function(e) {
      this.set("data.open", !this.data.open && this.data.children && this.data.children.length);
    }

  });

</script>