如何在Angular 2 Dragula中的可拖动元素上保留文本可选？

npm install ng2-dragula --save

import { DragulaService, DragulaDirective } from 'ng2-dragula';

constructor(private dragulaService: DragulaService) { }

ngOnInit() {
  this.dragulaService.createGroup('myGroup', {
    moves: (el, container, handle) => {
      // 在这里判断是否允许拖动元素
      // 返回true表示允许拖动，返回false表示禁止拖动
      return true;
    }
  });
}

<div [dragula]="'myGroup'">
  <div>可拖动元素1</div>
  <div>可拖动元素2</div>
  <div>可拖动元素3</div>
</div>

<div [dragula]="'myGroup'">
  <div contenteditable="true">可拖动元素1</div>
  <div contenteditable="true">可拖动元素2</div>
  <div contenteditable="true">可拖动元素3</div>
</div>