Remove checkbox of the parent node in React TreeView component

import * as ReactDOM from 'react-dom';
import * as React from 'react';
import {TreeViewComponent, NodeSelectEventArgs } from '@syncfusion/ej2-react-navigations';
import {enableRipple} from '@syncfusion/ej2-base';
enableRipple(true);

export default class App extends React.Component<{}, {}> {

   // Data source for TreeView component
   private Countries: { [key: string]: Object }[] = [
    { id: 1, name: 'India', hasChild: true, expanded: true },
    { id: 2, pid: 1, name: 'Assam' },
    { id: 3, pid: 1, name: 'Bihar' },
    { id: 4, pid: 1, name: 'Tamil Nadu' },
    { id: 6, pid: 1, name: 'Punjab' },
    { id: 7, name: 'Brazil', hasChild: true },
    { id: 8, pid: 7, name: 'Paraná' },
    { id: 9, pid: 7, name: 'Ceará' },
    { id: 10, pid: 7, name: 'Acre' },
    { id: 11, name: 'France', hasChild: true },
    { id: 12, pid: 11, name: 'Pays de la Loire' },
    { id: 13, pid: 11, name: 'Aquitaine' },
    { id: 14, pid: 11, name: 'Brittany' },
    { id: 15, pid: 11, name: 'Lorraine' },
    { id: 16, name: 'Australia', hasChild: true },
    { id: 17, pid: 16, name: 'New South Wales' },
    { id: 18, pid: 16, name: 'Victoria' },
    { id: 19, pid: 16, name: 'South Australia' },
    { id: 20, pid: 16, name: 'Western Australia' },
    { id: 21, name: 'China', hasChild: true },
    { id: 22, pid: 21, name: 'Guangzhou' },
    { id: 23, pid: 21, name: 'Shanghai' },
    { id: 24, pid: 21, name: 'Beijing' },
    { id: 25, pid: 21, name: 'Shantou' }
   ]

    private field:Object ={  dataSource: this.Countries, id: 'id', text: 'name', parentID: 'pid', hasChildren: 'hasChild' };
    private cssClass="custom";
    private showCheckBox: boolean = true;

    render() {
      return (
        <div className = 'control-pane'>
          <div className='control-section'>
            <div className='control_wrapper'>
              {/* Render TreeView */}
              <TreeViewComponent fields={this.field} cssClass={this.cssClass}  showCheckBox={this.showCheckBox} />
            </div>
          </div>
        </div>
      )
    }
}

ReactDOM.render(<App />, document.getElementById('sample'));

#loader {
    color: #008cff;
    height: 40px;
    left: 45%;
    position: absolute;
    top: 45%;
    width: 30%;
}

#treeparent {
    display: block;
    max-width: 350px;
    max-height: 350px;
    margin: auto;
    overflow: auto;
    border: 1px solid #dddddd;
    border-radius: 3px;
}
.custom .e-list-item.e-level-1 .e-text-content.e-icon-wrapper
  .e-checkbox-wrapper {
        display: none
    }