Komponentas

Component.js

import React, { Component } from 'react';

class Komponentas extends Component {
  constructor(props) {
    super(props);
    
    // mini duombaze
    this.state = {
      data: 'informacija'
    }
  }
  
  handleClick = () => {
    //siunciame duomenis
    this.setState({ data: 'pakeista info' });
  }
  
  render() {
    // gauname duomenis
    const info = this.state.data;
    return (
      <div>
        <p>{info}</p>
        <button onClick={() => this.handleClick}>Push the button</button>
      </div>
    );
  }
}