[polymer] import all elements

pkg/polymer/lib/elements/polymer-meta/polymer-meta.html

+<!--
+Copyright 2013 The Polymer Authors. All rights reserved.
+Use of this source code is governed by a BSD-style
+license that can be found in the LICENSE file.
+-->
+<!--
+/**
+ * @module Polymer Elements
+ */
+/**
+ * The `polymer-meta` elements provides a method of constructing a 
+ * self-organizing database.  It is useful to collate element meta-data for 
+ * things like catalogs and for sandbox.
+ *
+ * Example, an element folder has a `metadata.html` file in it, that contains a 
+ * polymer-meta, something like this:
+ *
+ *     <polymer-meta id="my-element">
+ *       <property name="color" type="color"></property>
+ *     </polymer-meta>
+ *
+ * An application can import as many of these files as it wants, and then use 
+ * polymer-meta again to access the collected data.
+ *
+ *     <script>
+ *       var meta = document.createElement('polymer-meta');
+ *       console.log(meta.list); // dump a list of all meta-data elements that have been created
+ *     </script>
+ *
+ * Use `byId(id)` to retrive a specific polymer-meta.
+ *
+ *     <script>
+ *       var meta = document.createElement('polymer-meta');
+ *       console.log(meta.byId('my-element'));
+ *     </script>
+ *
+ * By default all meta-data are stored in a signle databse.  If your meta-data 
+ * have different types and want them to be stored separately, use `type` to 
+ * differentiate them.
+ *
+ * @class polymer-meta
+ */
+-->
+<link rel="import" href="../polymer/polymer.html">
+
+<polymer-element name="polymer-meta" attributes="list label type">
+  <script>
+    (function() {
+      var SKIP_ID = 'meta';
+      var metaData = {}, metaArray = {};
+
+      Polymer('polymer-meta', {
+        alwaysPrepare: true,
+        /**
+         * The type of meta-data.  All meta-data with the same type with be
+         * stored together.
+         * 
+         * @attribute type
+         * @type string
+         * @default 'default'
+         */
+        type: 'default',
+        ready: function() {
+          this.idChanged();
+        },
+        get metaArray() {
+          var t = this.type;
+          if (!metaArray[t]) {
+            metaArray[t] = [];
+          }
+          return metaArray[t];
+        },
+        get metaData() {
+          var t = this.type;
+          if (!metaData[t]) {
+            metaData[t] = {};
+          }
+          return metaData[t];
+        },
+        idChanged: function(old) {
+          if (this.id && this.id !== SKIP_ID) {
+            this.unregister(this, old);
+            this.metaData[this.id] = this;
+            this.metaArray.push(this);
+          }
+        },
+        unregister: function(meta, id) {
+          delete this.metaData[id || meta.id];
+          var i = this.metaArray.indexOf(meta);
+          if (i >= 0) {
+            this.metaArray.splice(i, 1);
+          }
+        },
+        /**
+         * Returns a list of all meta-data elements with the same type.
+         * 
+         * @attribute list
+         * @type array
+         * @default []
+         */
+        get list() {
+          return this.metaArray;
+        },
+        /**
+         * Returns the first `<template>` in the `<polymer-meta>` subtree. This
+         * is useful to store element example.
+         *
+         *     <polymer-meta id="polymer-ui-toolbar" label="Polymer Toolbar">
+         *       <template>
+         *         <polymer-ui-toolbar theme="polymer-ui-light-theme">
+         *           <polymer-ui-icon-button icon="menu"></polymer-ui-icon-button>
+         *           <div flex>Title</div>
+         *           <polymer-ui-icon-button icon="add"></polymer-ui-icon-button>
+         *         </polymer-ui-toolbar>
+         *       </template>
+         *     </polymer-meta>
+         * 
+         * @attribute archetype
+         * @type node
+         * @default null
+         */
+        get archetype() {
+          return this.querySelector('template');
+        },
+        /**
+         * Retrieves meta-data by ID.
+         *
+         * @method byId
+         * @param {String} id The ID of the meta-data to be returned.
+         * @returns Returns meta-data.
+         */
+        byId: function(id) {
+          return this.metaData[id];
+        },
+        get childMetas() {
+          return this.querySelectorAll(this.localName);
+        }
+      });
+    })();
+  </script>
+</polymer-element>