REACT: State Change onClick Example

example.js

class SomeComponent extends React.Component {
  constructor(props) {
    super(props);
    this.state = {
      value: 1
    };
  }

  handleButtonChange() {
    this.setState({
      value: 2
    });
  }

  render() {
    return (
      <div>
        <h1>{this.state.value}</h1>
        <button onClick={() => this.handleButtonChange()}>Change State</button>
      </div>
    );
  }
}