Layout.js

class Layout extends PureComponent{
  constructor(props) {
    super(props)
    this.state = {
      showModal: false
    }
  }
  
  toggleModal = () => this.setState({ showsModal: !this.state.showModal })

  render() {
    <Fragment>
      <Button onClick={this.toggleModal}>Toggle modal</Button>
      //...
      <Modal open={this.state.showModal}/>
        //...
    </Fragment> 
  }
}