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在这里，我正在尝试构建一个工作演示来实现由@CaptainCodeman 编写的这篇博客文章中包含的代码——在 Polymer 2.0 中管理状态——超越父/子绑定在没有 Redux 的分离的 DOM 元素之间共享状态。

我收到以下错误。

run.plnkr.co/:5 获取https://cdn.rawgit.com/download/polymer-cdn/2.0.0/lib/webcomponentsjs/webcomponents-lite.min.js

run.plnkr.co/:1 获取https://polygit.org/polymer+v2.0.0/shadycss+webcomponents+1.0.0/components/my-options.html 500 ()

run.plnkr.co/:1 获取https://polygit.org/polymer+v2.0.0/shadycss+webcomponents+1.0.0/components/shared-styles.html 500 ()

my-view2.html:26
Uncaught ReferenceError:
MyOptionsMixin 未在 my-view2.html:26 中定义

有没有人有这个工作演示？

我的选项.html 
<link rel="import" href="../bower_components/polymer/polymer-element.html">
<link rel="import" href="../bower_components/paper-checkbox/paper-checkbox.html">

<dom-module id="my-options">
  <template>
    <style>
      :host {
        display: block;
        padding: 16px;
      }
      h3, p {
        margin: 8px 0;
      }
    </style>
    <h3>Options</h3>
    <p>
      <paper-checkbox checked="{{ options.subscribe }}">Send Notifications</paper-checkbox>
    </p>
  </template>

  <script>
    (function() {

      let optionsInstance = null;

      class MyOptions extends Polymer.Element {
        static get is() { return 'my-options'; }

        static get properties() {
          return {
            options: {
              type: Object,
              value: () => ({
                subscribe: false
              })
            },
            subscribers: {
              type: Array,
              value: () => []
            }
          }
        }

        static get observers() {
          return [
            'optionsChanged(options.*)'
          ]
        }

        constructor() {
          super();

          if (!optionsInstance) optionsInstance = this;
        }

        register(subscriber) {
          this.subscribers.push(subscriber);
          subscriber.options = this.options;
          subscriber.notifyPath('options');
        }

        unregister(subscriber) {
          var i = this.subscribers.indexOf(subscriber);
          if (i > -1) this.subscribers.splice(i, 1)
        }

        optionsChanged(change) {
          for(var i = 0; i < this.subscribers.length; i++) {
            this.subscribers[i].notifyPath(change.path);
          }
        }
      }

      window.customElements.define(MyOptions.is, MyOptions);

      MyOptionsMixin = (superClass) => {
        return class extends superClass {
          static get properties() {
            return {
              options: {
                type: Object
              }
            }
          }

          connectedCallback() {
            super.connectedCallback();
            optionsInstance.register(this);
          }

          disconnectedCallback() {
            super.disconnectedCallback();
            optionsInstance.unregister(this);
          }
        }
      }
    }());
  </script>
</dom-module>
我的-view2.html 
<link rel="import" href="../bower_components/polymer/polymer-element.html">

<link rel="import" href="my-options.html">
<link rel="import" href="shared-styles.html">

<dom-module id="my-view2">
  <template>
    <style include="shared-styles">
      :host {
        display: block;
        padding: 10px;
      }
    </style>

    <div class="card">
      <div class="circle">2</div>
      <h1>View Two</h1>
      <p>Ea duis bonorum nec, falli paulo aliquid ei eum.</p>
      <p>Id nam odio natum malorum, tibique copiosae expetenda mel ea.Detracto suavitate repudiandae no eum. Id adhuc minim soluta nam.Id nam odio natum malorum, tibique copiosae expetenda mel ea.</p>

      <p>Send notifications option is: <b>[[ options.subscribe ]]</b></p>
    </div>
  </template>

  <script>
    class MyView2 extends MyOptionsMixin(Polymer.Element) {
      static get is() { return 'my-view2'; }
    }

    window.customElements.define(MyView2.is, MyView2);
  </script>
</dom-module>

编辑：工作演示（已接受的答案分叉和编辑）

4

1 回答 1

1

工作的笨蛋

run.plnkr.co/:5 获取https://cdn.rawgit.com/download/polymer-cdn/2.0.0/lib/webcomponentsjs/webcomponents-lite.min.js

您的<script>标签导入了一个不存在的文件：

https://cdn.rawgit.com/download/polymer-cdn/2.0.0/lib/webcomponentsjs/webcomponents-lite.min.js

我会使用与polygit.orgPlunker 其余部分相同的 URL：

https://polygit.org/polymer+v2.0.0/shadycss+webcomponents+1.0.0/components/

此外，脚本名称不再包含min. 实际文件名是webcomponents-lite.js. <script>标签应如下所示：

<script src="https://polygit.org/polymer+v2.0.0/shadycss+webcomponents+1.0.0/components/webcomponentsjs/webcomponents-lite.js"></script>

run.plnkr.co/:1 获取https://polygit.org/polymer+v2.0.0/shadycss+webcomponents+1.0.0/components/my-options.html 500 ()

run.plnkr.co/:1 获取https://polygit.org/polymer+v2.0.0/shadycss+webcomponents+1.0.0/components/shared-styles.html 500 ()

my-view2.html设置<base href>为polygit.org，然后尝试导入my-options.html和shared-styles.html，这两者都只存在于 Plunker 沙箱中：

<!-- my-view2.html -->
<base href="https://polygit.org/polymer+v2.0.0/shadycss+webcomponents+1.0.0/components/">
<link rel="import" href="polymer/polymer-element.html">

<link rel="import" href="my-options.html"> <!-- https://polygit.org/polymer+v2.0.0/shadycss+webcomponents+1.0.0/components/my-options.html -->
<link rel="import" href="shared-styles.html"> <!-- https://polygit.org/polymer+v2.0.0/shadycss+webcomponents+1.0.0/components/shared-styles.html -->

此处导入的唯一需要来自的文件polygit.org是polymer-element.html，因此您可以删除<base>标记并将 URL 前缀移动到该导入：

<link rel="import" href="https://polygit.org/polymer+v2.0.0/shadycss+webcomponents+1.0.0/components/polymer/polymer-element.html">

my-view2.html:26 Uncaught ReferenceError: MyOptionsMixin 未在 my-view2.html:26 中定义

my-view2不声明/实例化my-options，因此script定义MyOptionsMixin永远不会执行。您可以通过在my-view2的模板中声明它来解决这个问题：

 <dom-module id="my-view2">
    <template>
      <my-options></my-options>
    </template>
    ...
 </dom-module>
于 2017-08-24T02:43:19.817 回答