JAVASCRIPT

add active class to li onclick react

const links = ['link1', 'link2', 'link3'];
const [active, setActive] = useState(null);

<ul>
  {links.map((link) => (
    <li className="nav-item">
      <a 
        href={`#${link}`} 
        className={`nav-link ${active == link && 'm-active'}`}
        onClick={() => setActive(link)}
      >{link}</a>
    </li>
  ))}
</ul>

add active class to button onclick react

class App extends React.Component {
  constructor(props) {
    super(props);

    this.state = {
      animate: false;
    }

    this.handleClick = this.handleClick.bind(this);
  }

  handleClick(e) {
    // modify the state, this will automatically recall render() below.
    this.setState((prevState) => {
      return { animate: !prevState.animate }
    });
  }

  render() {
    let animationClasses = (this.state.animate ? ' active': '');

    return (
      <div>
        <div className={`vote_card_hover${animationClasses}`}>
          <a>Test</a>
        </div>

        <div>
          <Button title="Toggle Animation" onClick={this.handleClick} />
        </div>
      </div>
    )
  }
}

add active class to button onclick react

class App extends React.Component {
  constructor(props) {
    super(props);

    this.state = {
      animate: false;
    }

    this.handleClick = this.handleClick.bind(this);
  }

  handleClick(e) {
    // modify the state, this will automatically recall render() below.
    this.setState((prevState) => {
      return { animate: !prevState.animate }
    });
  }

  render() {
    let animationClasses = (this.state.animate ? ' active': '');

    return (
      <div>
        <div className={`vote_card_hover${animationClasses}`}>
          <a>Test</a>
        </div>

        <div>
          <Button title="Toggle Animation" onClick={this.handleClick} />
        </div>
      </div>
    )
  }
}