third_party/polymer/v1_0/components/paper-spinner/paper-spinner.html

   1 <!--
   2 @license
   3 Copyright (c) 2015 The Polymer Project Authors. All rights reserved.
   4 This code may only be used under the BSD style license found at http://polymer.github.io/LICENSE.txt
   5 The complete set of authors may be found at http://polymer.github.io/AUTHORS.txt
   6 The complete set of contributors may be found at http://polymer.github.io/CONTRIBUTORS.txt
   7 Code distributed by Google as part of the polymer project is also
   8 subject to an additional IP rights grant found at http://polymer.github.io/PATENTS.txt
   9 -->
  10
  11 <link rel="import" href="../polymer/polymer.html">
  12 <link rel="import" href="../paper-styles/color.html">
  13 <link rel="import" href="../iron-flex-layout/iron-flex-layout.html">
  14
  15 <!--
  16 Element providing material design circular spinner.
  17
  18     <paper-spinner active></paper-spinner>
  19
  20 The default spinner cycles between four layers of colors; by default they are
  21 blue, red, yellow and green. It can be customized so that it uses one color only
  22 by setting all the layer colors to the same value.
  23
  24 ### Accessibility
  25
  26 Alt attribute should be set to provide adequate context for accessibility. If not provided,
  27 it defaults to 'loading'.
  28 Empty alt can be provided to mark the element as decorative if alternative content is provided
  29 in another form (e.g. a text block following the spinner).
  30
  31     <paper-spinner alt="Loading contacts list" active></paper-spinner>
  32
  33 ### Styling
  34
  35 The following custom properties and mixins are available for styling:
  36
  37 Custom property | Description | Default
  38 ----------------|-------------|----------
  39 `--paper-spinner-layer-1-color` | Color of the first spinner rotation | `--google-blue-500`
  40 `--paper-spinner-layer-2-color` | Color of the second spinner rotation | `--google-red-500`
  41 `--paper-spinner-layer-3-color` | Color of the third spinner rotation | `--google-yellow-500`
  42 `--paper-spinner-layer-4-color` | Color of the fourth spinner rotation | `--google-green-500`
  43
  44 @group Paper Elements
  45 @element paper-spinner
  46 @hero hero.svg
  47 @demo demo/index.html
  48 -->
  49
  50 <dom-module id="paper-spinner">
  51
  52   <link rel="import" type="css" href="paper-spinner.css">
  53
  54   <template>
  55
  56     <div id="spinnerContainer" class-name="[[_spinnerContainerClassName]]">
  57       <div class="spinner-layer layer-1">
  58         <div class="circle-clipper left">
  59           <div class="circle"></div>
  60         </div><div class="gap-patch">
  61           <div class="circle"></div>
  62         </div><div class="circle-clipper right">
  63           <div class="circle"></div>
  64         </div>
  65       </div>
  66
  67       <div class="spinner-layer layer-2">
  68         <div class="circle-clipper left">
  69           <div class="circle"></div>
  70         </div><div class="gap-patch">
  71           <div class="circle"></div>
  72         </div><div class="circle-clipper right">
  73           <div class="circle"></div>
  74         </div>
  75       </div>
  76
  77       <div class="spinner-layer layer-3">
  78         <div class="circle-clipper left">
  79           <div class="circle"></div>
  80         </div><div class="gap-patch">
  81           <div class="circle"></div>
  82         </div><div class="circle-clipper right">
  83           <div class="circle"></div>
  84         </div>
  85       </div>
  86
  87       <div class="spinner-layer layer-4">
  88         <div class="circle-clipper left">
  89           <div class="circle"></div>
  90         </div><div class="gap-patch">
  91           <div class="circle"></div>
  92         </div><div class="circle-clipper right">
  93           <div class="circle"></div>
  94         </div>
  95       </div>
  96     </div>
  97
  98   </template>
  99
 100   <script>
 101
 102     Polymer({
 103
 104       is: 'paper-spinner',
 105
 106       listeners: {
 107         'animationend': 'reset',
 108         'webkitAnimationEnd': 'reset'
 109       },
 110
 111       properties: {
 112
 113         /**
 114          * Displays the spinner.
 115          *
 116          * @attribute active
 117          * @type boolean
 118          * @default false
 119          */
 120         active: {
 121           type: Boolean,
 122           value: false,
 123           reflectToAttribute: true,
 124           observer: '_activeChanged'
 125         },
 126
 127         /**
 128          * Alternative text content for accessibility support.
 129          * If alt is present, it will add an aria-label whose content matches alt when active.
 130          * If alt is not present, it will default to 'loading' as the alt value.
 131          *
 132          * @attribute alt
 133          * @type string
 134          * @default 'loading'
 135          */
 136         alt: {
 137           type: String,
 138           value: 'loading',
 139           observer: '_altChanged'
 140         },
 141
 142         /**
 143          * True when the spinner is going from active to inactive. This is represented by a fade
 144          * to 0% opacity to the user.
 145          */
 146         _coolingDown: {
 147           type: Boolean,
 148           value: false
 149         },
 150
 151         _spinnerContainerClassName: {
 152           type: String,
 153           computed: '_computeSpinnerContainerClassName(active, _coolingDown)'
 154         }
 155
 156       },
 157
 158       _computeSpinnerContainerClassName: function(active, coolingDown) {
 159         return [
 160           active || coolingDown ? 'active' : '',
 161           coolingDown ? 'cooldown' : ''
 162         ].join(' ');
 163       },
 164
 165       _activeChanged: function(active, old) {
 166         this._setAriaHidden(!active);
 167         if (!active && old) {
 168           this._coolingDown = true;
 169         }
 170       },
 171
 172       _altChanged: function(alt) {
 173         // user-provided `aria-label` takes precedence over prototype default
 174         if (alt === this.getPropertyInfo('alt').value) {
 175           this.alt = this.getAttribute('aria-label') || alt;
 176         } else {
 177           this._setAriaHidden(alt==='');
 178           this.setAttribute('aria-label', alt);
 179         }
 180       },
 181
 182       _setAriaHidden: function(hidden) {
 183         var attr = 'aria-hidden';
 184         if (hidden) {
 185           this.setAttribute(attr, 'true');
 186         } else {
 187           this.removeAttribute(attr);
 188         }
 189       },
 190
 191       reset: function() {
 192         this.active = false;
 193         this._coolingDown = false;
 194       }
 195
 196     });
 197
 198   </script>
 199
 200 </dom-module>