third_party/polymer/v1_0/components-chromium/iron-meta/iron-meta.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 --><html><head><link rel="import" href="../polymer/polymer.html">
  10
  11 <!--
  12 `iron-meta` is a generic element you can use for sharing information across the DOM tree.
  13 It uses [monostate pattern](http://c2.com/cgi/wiki?MonostatePattern) such that any
  14 instance of iron-meta has access to the shared
  15 information. You can use `iron-meta` to share whatever you want (or create an extension
  16 [like x-meta] for enhancements).
  17
  18 The `iron-meta` instances containing your actual data can be loaded in an import,
  19 or constructed in any way you see fit. The only requirement is that you create them
  20 before you try to access them.
  21
  22 Examples:
  23
  24 If I create an instance like this:
  25
  26     <iron-meta key="info" value="foo/bar"></iron-meta>
  27
  28 Note that value="foo/bar" is the metadata I've defined. I could define more
  29 attributes or use child nodes to define additional metadata.
  30
  31 Now I can access that element (and it's metadata) from any iron-meta instance
  32 via the byKey method, e.g.
  33
  34     meta.byKey('info').getAttribute('value').
  35
  36 Pure imperative form would be like:
  37
  38     document.createElement('iron-meta').byKey('info').getAttribute('value');
  39
  40 Or, in a Polymer element, you can include a meta in your template:
  41
  42     <iron-meta id="meta"></iron-meta>
  43     ...
  44     this.$.meta.byKey('info').getAttribute('value');
  45
  46 @group Iron Elements
  47 @demo demo/index.html
  48 @hero hero.svg
  49 @element iron-meta
  50 -->
  51
  52 </head><body><script src="iron-meta-extracted.js"></script></body></html>