gistfile1.txt

P A R E N T  App.js
###################### 

class App extends Component {
  state = {
  casinos: [],
  isbonus: false,
}

callbackFunction = (childData) => { this.setState({isbonus: childData})};

  render() {

    return(

 <BrowserRouter>
   <Fragment>
     <li className={ this.state.isbonus ? 'current' : '' }>
        <NavLink
           exact
           to="/bonuses"
           data-hover="Alla Bonusar">
           Alla Bonusar
        </NavLink>
     </li>

  <Route exact path="/" component={Home} />
   <Route
     exact
     path="/bonuses"
     component={Bonuses}
     parentCallback = {this.callbackFunction} />
 
  </Fragment>
</BrowserRouter>

    );
  }
}
export default App;


C H I L D  bonuses.js
######################################

class Bonuses extends Component {
  state = {
  casinos: []
}

sendData = () => {
  this.props.parentCallback(true);
};