content: import React, { Component } from 'react';
  import SomeComponent from './SomeComponent';
  import './App.css';
  
  class App extends Component {
  
    constructor(props) {
      super(props);
      this.state = {status: true, visible: true};
      this.handleClick = this.handleClick.bind(this);
      this.handleToggleClick = this.handleToggleClick.bind(this);
    }
  
    handleClick() {
      this.setState((prevState, props) => ({
        status: !prevState.status
      }));
    }
  
    handleToggleClick() {
      this.setState((prevState, props) => ({
        visible: !prevState.visible
      }));
    }
  
    render() {
      return (
        <div className="App">
          <button onClick={this.handleClick}>change state / hello prop</button>
          <button onClick={this.handleToggleClick}>Toggle Remove/Add Element</button>
          { this.state.visible ? <SomeComponent hello={this.state.status} />: <div />}
        </div>
      );
    }
  }
  
  export default App;
  