未捕获的TypeError：超级表达式必须为null或函数，且未定义-Reactjs运行时错误

Question

我在react js中遇到运行时错误“未捕获的TypeError：超级表达式必须为null或函数，且未定义”

import React from 'react';
import { render } from 'react-dom';

import { TransmittalForm, DocumentCart } from '../components';


class TransmittalsForm extends React.Component {
constructor() {
    super();
    this.state = {
        items: []
    };

    this.parentOnChange = this.parentOnChange.bind(this);
}

componentDidMount() {
    this.state.items = [];
}

parentOnChange(docItems) {
    this.setState({
        items: docItems
    });
}

render() {
    return (
        <div className="transmittals">
            <TransmittalForm docItems={this.state.items} />
            <DocumentCart docItemsChange={this.parentOnChange} />
        </div>
    );
  }
 }

 render(
  <TransmittalsForm />,
  document.getElementById('people-table')
 );

我正在使用React v15.2.0。并且在npm运行build时没有看到任何错误。