WebCompDev / COMPONENTS

  <!--
  @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
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  <link rel="import" href="../polymer/polymer.html">

  <link rel="import" href="../paper-material/paper-material.html">

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

  
  <!--

  Material design: [Cards](https://www.google.com/design/spec/components/cards.html)

  
  `paper-card` is a container with a drop shadow.
  
  Example:
  
      <paper-card heading="Card Title">
        <div class="card-content">Some content</div>
        <div class="card-actions">
          <paper-button>Some action</paper-button>
        </div>
      </paper-card>
  

  Example - top card image:
  
      <paper-card heading="Card Title" image="/path/to/image.png">
        ...
      </paper-card>

  ### Accessibility
  
  By default, the `aria-label` will be set to the value of the `heading` attribute.
  
  ### Styling
  
  The following custom properties and mixins are available for styling:
  
  Custom property | Description | Default
  ----------------|-------------|----------

  `--paper-card-header-color` | The color of the header text | `#000`
  `--paper-card-header` | Mixin applied to the card header section | `{}`
  `--paper-card-header-text` | Mixin applied to the title in the card header section | `{}`
  `--paper-card-header-image` | Mixin applied to the image in the card header section | `{}`
  `--paper-card-header-image-text` | Mixin applied to the text overlapping the image in the card header section | `{}`
  `--paper-card-content` | Mixin applied to the card content section| `{}`
  `--paper-card-actions` | Mixin applied to the card action section | `{}`
  `--paper-card` | Mixin applied to the card | `{}`
  
  @group Paper Elements
  @element paper-card
  @demo demo/index.html
  -->
  
  <dom-module id="paper-card">
    <template>

      <style include="paper-material">

        :host {
          display: inline-block;
          position: relative;
          box-sizing: border-box;

          background: #fff;
          border-radius: 2px;

          @apply(--paper-card);
        }
  

        /* IE 10 support for HTML5 hidden attr */
        [hidden] {
          display: none !important;
        }
  
        .header {
          position: relative;

          border-top-left-radius: inherit;
          border-top-right-radius: inherit;
          overflow: hidden;

          @apply(--paper-card-header);
        }
  

        .header img {

          width: 100%;

          pointer-events: none;

          @apply(--paper-card-header-image);
        }
  
        .header .title-text {
          padding: 16px;
          font-size: 24px;

          font-weight: bold;

          color: var(--paper-card-header-color, #000);

          @apply(--paper-card-header-text);
        }
  
        .header .title-text.over-image {
          position: absolute;
          bottom: 0px;

          @apply(--paper-card-header-image-text);
        }
  
        :host ::content .card-content {
          padding: 16px;
          position:relative;

          @apply(--paper-card-content);
        }
  
        :host ::content .card-actions {
          border-top: 1px solid #e8e8e8;
          padding: 5px 16px;
          position:relative;

          @apply(--paper-card-actions);
        }
      </style>
  

      <div class="header">

        <img hidden$="[[!image]]" src="[[image]]">

        <div hidden$="[[!heading]]" class$="[[_computeHeadingClass(image)]]">[[heading]]</div>
      </div>

      <content></content>

    </template>
  

  </dom-module>
  
  <script>
  
    Polymer({
  
      is: 'paper-card',
  
      properties: {
  
        /**
         * The title of the card.
         */
        heading: {
          type: String,
          value: '',
          observer: '_headingChanged'
        },
  
        /**
         * The url of the title image of the card.
         */
        image: {
          type: String,
          value: ''

        },
  

        /**
         * The z-depth of the card, from 0-5.
         */
        elevation: {
          type: Number,
          value: 1,
          reflectToAttribute: true

        },
  

        /**
         * Set this to true to animate the card shadow when setting a new
         * `z` value.
         */
        animatedShadow: {
          type: Boolean,
          value: false

        },
  

        /**
         * Read-only property used to pass down the `animatedShadow` value to
         * the underlying paper-material style (since they have different names).
         */
        animated: {
          type: Boolean,
          reflectToAttribute: true,
          readOnly: true,
          computed: '_computeAnimated(animatedShadow)'

        }

      },
  
      _headingChanged: function(heading) {
        var label = this.getAttribute('aria-label');
        this.setAttribute('aria-label', heading);
      },
  
      _computeHeadingClass: function(image) {
        var cls = 'title-text';
        if (image)
          cls += ' over-image';
        return cls;
      },
  
      _computeAnimated: function(animatedShadow) {
        return animatedShadow;
      }
    });
  </script>