javascript - polymer 2.x : Behavior mixins using class extension; error: Class constructor cannot be invoked without 'new'

Question

我正在尝试使用类扩展实现行为混合，如 here 所述和 here .

设置列表-text.html

<link rel="import" href="settings-item-switch.html">
...
<script>
  class SettingsListText extends SettingsItemSwitch(Polymer.Element) {

但我不断收到以下控制台错误。

settings-list-text.html:32 Uncaught TypeError: Class constructor SettingsItemSwitch cannot be invoked without 'new' at settings-list-text.html:32

设置项开关.html

<script>
  class SettingsItemSwitch extends Polymer.Element {

我如何使用 Polymer 2.x 导入使用类 es6 扩展的自定义行为混合？

Answer 1

看看https://www.polymer-project.org/2.0/docs/devguide/custom-elements#mixins

您的混入代码应如下所示:

<script>
    /**
     * @mixinFunction
     * @polymer
     */
    MyMixin = (superclass) =>
        /**
       * @mixinClass
       * @polymer
       */
        class extends superclass {
            constructor() {
                super();
            }

            myFunc(myParam) {
                //do something
            }
        }
</script>