selecting-one-item-using-the-core-selector-element.html

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<!--
# Selecting one item using the Core Selector element

Shows how to select item from a collection using the `<core-selector>` Polymer element.

You can use `<core-selector>` for managing selection state and configure
it by passing arguments. For example, you can set and access the selected
item by using `<core-selector>`'s `selected` property:

    <core-selector id="selector" selected="1">
      <template repeat="{{color in colors}}">
        <div value="{{color}}">{{color}}</div>
      </template>
    </core-selector>

You can get the value of `selected` (the index of the selected items from `colors`) in your template like this:

    <div>{{colors[$.selector.selected]}}</div>

Polymer assigns a `.core-selected` class to selected items, and you can define
styles for this class. You can also configure the name to something other than
`.core-selected`.

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

[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 id="selector" selected="1">
      <template repeat="{{color in colors}}">
        <div value="{{color}}">{{color}}</div>
      </template>
    </core-selector>
    <hr>
    <div>{{colors[$.selector.selected]}}</div>
  </template>
  <script>
    Polymer({
      created: function() {
        this.colors = ['red', 'green', 'blue'];
      }
    });
  </script>
</polymer-element>