如何让纸质菜单按钮工作？答案

【问题标题】：How to get paper-menu-button to work?如何让纸质菜单按钮工作？
【发布时间】：2017-07-10 15:46:09
【问题描述】：

我不断收到错误消息，抱怨在本地提供以下演示时无法运行动画。 Although it does work in my jsBin.

http://jsbin.com/kadugokade/edit?html,console,output

<!DOCTYPE html>
<html>
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width">
  <title>JS Bin</title>

  <base href="http://polygit.org/polymer+:master/components/">
  <script src="webcomponentsjs/webcomponents-lite.js"></script>
  <link rel="import" href="polymer/polymer-element.html">
  <link rel="import" href="paper-menu-button/paper-menu-button.html">
  <link rel="import" href="paper-icon-button/paper-icon-button.html">
  <link rel="import" href="paper-listbox/paper-listbox.html">
  <link rel="import" href="paper-item/paper-item.html">
  <link rel="import" href="iron-icons/iron-icons.html">
  <link rel="import" href="iron-icon/iron-icon.html">

  <!-- Ensure Web Animations polyfill is loaded since neon-animation 2.0 doesn't import it -->
  <link rel="import" href="neon-animation/web-animations.html">

</head>
<body>
  <dom-module id="my-el">
    <template>
      <paper-menu-button>
        <paper-icon-button icon="menu" slot="dropdown-trigger" alt="menu"></paper-icon-button>
        <paper-listbox slot="dropdown-content">
          <paper-item>alpha</paper-item>
          <paper-item>beta</paper-item>
          <paper-item>gamma</paper-item>
          <paper-item>delta</paper-item>
          <paper-item>epsilon</paper-item>
        </paper-listbox>
      </paper-menu-button>
    </template>
    <script>
      class MyEl extends Polymer.Element {
        static get is() { return 'my-el' }
      }
      customElements.define(MyEl.is, MyEl);
    </script>
  </dom-module>

  <my-el></my-el>
</body>
</html>

【问题讨论】：

标签： polymer web-component paper-elements polymer-2.x web-animations

【解决方案1】：

检查您是否安装了以下导入所需的web-animations-js/ 目录。

bower_components/neon-animation/web-animations.html

<script src="../web-animations-js/web-animations-next-lite.min.js"></script>

您必须使用以下方式导入它：

bower install --save web-animations/web-animations-js

【讨论】：