paper-menu.html 4.06 KB
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@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="../iron-menu-behavior/iron-menu-behavior.html">
<link rel="import" href="../paper-styles/paper-styles.html">

<!--
`<paper-menu>` implements an accessible menu control with Material Design styling. The focused item
is highlighted, and the selected item has bolded text.

    <paper-menu>
      <paper-item>Item 1</paper-item>
      <paper-item>Item 2</paper-item>
    </paper-menu>

An initial selection can be specified with the `selected` attribute.

    <paper-menu selected="0">
      <paper-item>Item 1</paper-item>
      <paper-item>Item 2</paper-item>
    </paper-menu>

Make a multi-select menu with the `multi` attribute. Items in a multi-select menu can be deselected,
and multiple item can be selected.

    <paper-menu multi>
      <paper-item>Item 1</paper-item>
      <paper-item>Item 2</paper-item>
    </paper-menu>

### Styling

The following custom properties and mixins are available for styling:

Custom property | Description | Default
----------------|-------------|----------
`--paper-menu-background-color`   | Menu background color                                            | `--primary-background-color`
`--paper-menu-color`               | Menu foreground color                                            | `--primary-text-color`
`--paper-menu-disabled-color`     | Foreground color for a disabled item                             | `--disabled-text-color`
`--paper-menu`                    | Mixin applied to the menu                                        | `{}`
`--paper-menu-selected-item`      | Mixin applied to the selected item                               | `{}`
`--paper-menu-focused-item`       | Mixin applied to the focused item                                | `{}`
`--paper-menu-focused-item-after` | Mixin applied to the ::after pseudo-element for the focused item | `{}`

### Accessibility

`<paper-menu>` has `role="menu"` by default. A multi-select menu will also have
`aria-multiselectable` set. It implements key bindings to navigate through the menu with the up and
down arrow keys, esc to exit the menu, and enter to activate a menu item. Typing the first letter
of a menu item will also focus it.

@group Paper Elements
@element paper-menu
@hero hero.svg
@demo demo/index.html
-->

<dom-module id="paper-menu">

  <style>

    :host {
      display: block;
      padding: 8px 0;

      background: var(--paper-menu-background-color, --primary-background-color);
      color: var(--paper-menu-color, --primary-text-color);

      @apply(--paper-menu);
    }

    /* need a wrapper element to make this higher specificity than the :host rule in paper-item */
    .content > ::content > .iron-selected {
      font-weight: bold;

      @apply(--paper-menu-selected-item);
    }

    .content > ::content > [disabled] {
      color: var(--paper-menu-disabled-color, --disabled-text-color);
    }

    .content > ::content > *:focus {
      position: relative;
      outline: 0;

      @apply(--paper-menu-focused-item);
    }

    .content > ::content > *:focus:after {
      @apply(--layout-fit);
      background: currentColor;
      /* FIXME move to paper-styles for next widget */
      opacity: 0.12;
      content: '';

      @apply(--paper-menu-focused-item-after);
    }

    .content > ::content > *[colored]:focus:after {
      opacity: 0.26;
    }

  </style>

  <template>

    <div class="content">
      <content></content>
    </div>

  </template>

</dom-module>

<script>

(function() {

  Polymer({

    is: 'paper-menu',

    behaviors: [
      Polymer.IronMenuBehavior
    ]

  });

})();

</script>