paper-icon-button.html 4.7 KB
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<link rel="import" href="../polymer/polymer.html">
<link rel="import" href="../iron-icon/iron-icon.html">
<link rel="import" href="../iron-flex-layout/iron-flex-layout.html">
<link rel="import" href="../paper-styles/default-theme.html">
<link rel="import" href="../paper-behaviors/paper-button-behavior.html">
<link rel="import" href="../paper-behaviors/paper-inky-focus-behavior.html">
<link rel="import" href="../paper-ripple/paper-ripple.html">

<!--
Material Design: <a href="http://www.google.com/design/spec/components/buttons.html">Buttons</a>

`paper-icon-button` is a button with an image placed at the center. When the user touches
the button, a ripple effect emanates from the center of the button.

`paper-icon-button` includes a default icon set.  Use `icon` to specify which icon
from the icon set to use.

    <paper-icon-button icon="menu"></paper-icon-button>

See [`iron-iconset`](#iron-iconset) for more information about
how to use a custom icon set.

Example:

    <link href="path/to/iron-icons/iron-icons.html" rel="import">

    <paper-icon-button icon="favorite"></paper-icon-button>
    <paper-icon-button src="star.png"></paper-icon-button>

###Styling

Style the button with CSS as you would a normal DOM element. If you are using the icons
provided by `iron-icons`, they will inherit the foreground color of the button.

    /* make a red "favorite" button */
    <paper-icon-button icon="favorite" style="color: red;"></paper-icon-button>

By default, the ripple is the same color as the foreground at 25% opacity. You may
customize the color using this selector:

    /* make #my-button use a blue ripple instead of foreground color */
    #my-button::shadow #ripple {
      color: blue;
    }

The opacity of the ripple is not customizable via CSS.

The following custom properties and mixins are available for styling:

Custom property | Description | Default
----------------|-------------|----------
`--paper-icon-button-disabled-text` | The color of the disabled button | `--primary-text-color`
`--paper-icon-button-ink-color` | Selected/focus ripple color | `--default-primary-color`
`--paper-icon-button` | Mixin for a button | `{}`
`--paper-icon-button-disabled` | Mixin for a disabled button | `{}`

@group Paper Elements
@element paper-icon-button
@demo demo/index.html
-->

<dom-module id="paper-icon-button">
  <style>

    :host {
      display: inline-block;
      position: relative;
      padding: 8px;
      outline: none;
      -webkit-tap-highlight-color: rgba(0,0,0,0);
      -webkit-user-select: none;
      -moz-user-select: none;
      -ms-user-select: none;
      user-select: none;
      cursor: pointer;
      z-index: 0;

      @apply(--paper-icon-button);
    }

    :host #ink {
      color: var(--paper-icon-button-ink-color, --primary-text-color);
      opacity: 0.6;
    }

    :host([disabled]) {
      color: var(--paper-icon-button-disabled-text, --disabled-text-color);
      pointer-events: none;
      cursor: auto;
      @apply(--paper-icon-button-disabled);
    }
  </style>
  <template>
    <paper-ripple id="ink" class="circle" center></paper-ripple>
    <iron-icon id="icon" src="[[src]]" icon="[[icon]]" alt$="[[alt]]"></iron-icon>
  </template>
</dom-module>
<script>
  Polymer({
    is: 'paper-icon-button',

    hostAttributes: {
      role: 'button',
      tabindex: '0'
    },

    behaviors: [
      Polymer.PaperInkyFocusBehavior
    ],

    properties: {
      /**
       * The URL of an image for the icon. If the src property is specified,
       * the icon property should not be.
       */
      src: {
        type: String
      },

      /**
       * Specifies the icon name or index in the set of icons available in
       * the icon's icon set. If the icon property is specified,
       * the src property should not be.
       */
      icon: {
        type: String
      },

      /**
       * Specifies the alternate text for the button, for accessibility.
       */
      alt: {
        type: String,
        observer: "_altChanged"
      }
    },

    _altChanged: function(newValue, oldValue) {
      var label = this.getAttribute('aria-label');

      // Don't stomp over a user-set aria-label.
      if (!label || oldValue == label) {
        this.setAttribute('aria-label', newValue);
      }
    }
  });
</script>