如何在Framework7中取消选中自定义设计单选按钮？

<div class="list">
  <ul>
    <li>
      <label class="item-radio item-content">
        <input type="radio" name="radioButtonGroup" id="radioButton1">
        <i class="icon icon-radio"></i>
        <div class="item-inner">
          <div class="item-title">选项1</div>
        </div>
      </label>
    </li>
    <li>
      <label class="item-radio item-content">
        <input type="radio" name="radioButtonGroup" id="radioButton2">
        <i class="icon icon-radio"></i>
        <div class="item-inner">
          <div class="item-title">选项2</div>
        </div>
      </label>
    </li>
  </ul>
</div>

<script>
  // 取消选中单选按钮
  var radioButton = document.getElementById("radioButton1");
  radioButton.checked = false;
</script>