Javascript 清除按钮赢得'；无法清除所有输入字段

使用Vaadin_网格单击“清除”按钮时，不会使用旁边的（+）清除添加的位置字段

加价 按+符号可添加位置部分的网格作为新位置

<vaadin-grid-column>
   <template class="header">
   POSITION
   </template>
   <template>
   [[item.position]]
   </template>
</vaadin-grid-column>

用于添加新位置输入字段的逻辑

_addPosition(e) {

   let positionGroup = this.$.positionGroup;
   let setId = positionGroup.getElementsByTagName('input').length;
   let newPosition = document.createElement('input');

   newPosition.style.display = 'block';
   newPosition.type = 'text';
   newPosition.name = 'text';
   newPosition.setAttribute('name', 'position');
   newPosition.setAttribute('placeholder', 'Position');
   newPosition.id = 'position' + setId;

   positionGroup.insertAdjacentElement('beforeend', newPosition);

}

_clearForm() {
   this.set('_contact.isPrimaryContact', false);
   this.$.isPrimary.setAttribute('icon', 'vaadin:icons:check-box-outline-blank');

   this.set('_contact', {});
   this.set('_contact.contactPhones', [])
   this.set('_contact.contactMethodId', 0);
   this._contact.contactPhones.push({
      "phoneNumber": "",
      "phoneExtension": "",
      "phoneTypeId": null
   })
}

_clear() {
   this._clearForm();                
   this.$.successMsgBox._infoMessageHide = true;
   this.$.errorMsgBox._infoMessageHide = true;
}

_addPosition(e) {

   let positionGroup = this.$.positionGroup;
   let setId = positionGroup.getElementsByTagName('input').length;
   let newPosition = document.createElement('input');

   newPosition.style.display = 'block';
   newPosition.type = 'text';
   newPosition.name = 'text';
   newPosition.setAttribute('name', 'position');
   newPosition.setAttribute('placeholder', 'Position');
   newPosition.id = 'position' + setId;

   positionGroup.insertAdjacentElement('beforeend', newPosition);

}