paper-input-error.html

<!--
@license
Copyright (c) 2015 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
-->

<link rel="import" href="../polymer/polymer.html">
<link rel="import" href="../paper-styles/paper-styles.html">
<link rel="import" href="paper-input-addon-behavior.html">

<!--
`<paper-input-error>` is an error message for use with `<paper-input-container>`. The error is
displayed when the `<paper-input-container>` is `invalid`.

    <paper-input-container>
      <input is="iron-input" pattern="[0-9]*">
      <paper-input-error>Only numbers are allowed!</paper-input-error>
    </paper-input-container>

### Styling

The following custom properties and mixins are available for styling:

Custom property | Description | Default
----------------|-------------|----------
`--paper-input-container-invalid-color` | The foreground color of the error | `--google-red-500`
`--paper-input-error`                   | Mixin applied to the error        | `{}`
-->
<dom-module id="paper-input-error">

  <style>

    :host {
      /* need to use display: none for role="alert" */
      display: none;
      float: left;

      color: var(--paper-input-container-invalid-color, --google-red-500);

      @apply(--paper-font-caption);
      @apply(--paper-input-error);
    }

    :host([invalid]) {
      display: inline-block;
    };

  </style>

  <template>

    <content></content>

  </template>

</dom-module>

<script>

(function() {

  Polymer({

    is: 'paper-input-error',

    behaviors: [
      Polymer.PaperInputAddonBehavior
    ],

    hostAttributes: {
      'role': 'alert'
    },

    properties: {

      /**
       * True if the error is showing.
       */
      invalid: {
        readOnly: true,
        reflectToAttribute: true,
        type: Boolean
      }

    },

    update: function(state) {
      this._setInvalid(state.invalid);
    }

  })

})();

</script>