无法在React中从子组件更改父组件的状态

class ParentComponent extends React.Component {
  constructor(props) {
    super(props);
    this.state = {
      parentState: '初始值'
    };
  }

  updateParentState = (newState) => {
    this.setState({ parentState: newState });
  }

  render() {
    return (
      <div>
        <ChildComponent updateParentState={this.updateParentState} />
      </div>
    );
  }
}

class ChildComponent extends React.Component {
  handleClick = () => {
    this.props.updateParentState('新的状态');
  }

  render() {
    return (
      <button onClick={this.handleClick}>点击修改父组件状态</button>
    );
  }
}