纹波效果不起作用材料组件中的mdc-icon-toggle

Question

刚开始material components。我正在尝试mdc-icon-toggle，HTML代码

<i class="mdc-icon-toggle material-icons" role="button" aria-pressed="false" aria-label="Add to favorites" tabindex="0"         
    data-toggle-on='{"label": "Remove from favorites", "content": "favorite"}'
    data-toggle-off='{"label": "Add to favorites", "content": "favorite_border"}' 
    data-mdc-auto-init="MDCIconToggle">
      favorite_border
 </i>

JS代码

const iconEl = document.querySelector('.mdc-icon-toggle');

iconEl.addEventListener('MDCIconToggle:change', ({detail}) => {
  alert(detail.isOn)
});

基本功能工作正常，我能够听到这个事件但是当我点击图标时，涟漪效果不能正常工作，图标周围的阴影永远不会。我错过了一些东西，因为这也是单选按钮吗？

Answer 1

我正在学习MDC。

使用此表单更好地工作，将javascript代码放在BODY标记的末尾：

<i class="mdc-icon-toggle material-icons" role="button" aria-pressed="false" aria-label="Add to favorites" tabindex="0"         
    data-toggle-on='{"label": "Remove from favorites", "content": "favorite"}'
    data-toggle-off='{"label": "Add to favorites", "content": "favorite_border"}'>
      favorite_border
 </i>


<script type="text/javascript">
(function() {
      /* MDC Ripple for Toggle button */
      var nodes = document.querySelectorAll('.mdc-icon-toggle');
      for (var i = 0, node; node = nodes[i]; i++) {
        mdc.iconToggle.MDCIconToggle.attachTo(node);
      }
})();
</script>