selecting-many-items-using-the-core-selector-element.html

<!--
Copyright (c) 2014 The Polymer Project Authors. All rights reserved.
This code may only be used under the BSD style license found at http://polymer.github.io/LICENSE.txt
The complete set of authors may be found at http://polymer.github.io/AUTHORS.txt
The complete set of contributors may be found at http://polymer.github.io/CONTRIBUTORS.txt
Code distributed by Google as part of the polymer project is also
subject to an additional IP rights grant found at http://polymer.github.io/PATENTS.txt
-->

<!--
# Selecting many items using the Core Selector element

Shows how to select multiple items using the `<core-selector>` Polymer element.

See [Selecting one item using the Core Selector element](selecting-one-item-using-the-core-selector-element.html)
for an introduction to `<core-selector>'.

Use `<core-selector>` with the `multi` argument to select
mulitple values. Use the `valueattr` argument to specify the attribute to be
used for 'selected' attribute (without `valueattr`, `<core-selector>` uses the
index of the selected items).  This sample uses the `value` attribute of the
child `<div>` elements for the `selected` attribute.

    <core-selector id="cs"
                   selected="{{selected}}"
                   multi
                   valueattr="value">
      <template repeat="{{color in colors}}">
        <div value="{{color}}">{{color}}</div>
      </template>
    </core-selector>

Read the
[official documentation for `core-selector`](http://www.polymer-project.org/docs/elements/core-elements.html#core-selector).

[jsbin for multi select](http://jsbin.com/vuriri/edit)
[jsbin for single select](http://jsbin.com/hamuf/edit)
-->

<link rel="import" href="../../components/polymer/polymer.html">
<link rel="import" href="../../components/core-selector/core-selector.html">

<polymer-element name="my-element">
  <template>
    <style>
      .core-selected {
        font-weight: bold;
      }
    </style>
    <core-selector selected="{{selected}}" multi valueattr="value">
      <template repeat="{{color in colors}}">
        <div value="{{color}}">{{color}}</div>
      </template>
    </core-selector>
    <hr>
    <template repeat="{{color in selected}}">
      <div>{{color}}</div>
    </template>
  </template>
  <script>
    Polymer({
      created: function() {
        this.colors = ['red', 'green', 'blue'];
        this.selected = this.colors[1];
      }
    });
  </script>
</polymer-element>