Basic React Counter App

gistfile1.txt

class Button extends React.Component {

	handleClick = () => {
  	this.props.onClickFunction(this.props.incrementValue);
  }

	render() {
  	return(
    	<button 
      onClick={this.handleClick}>
      	+{this.props.incrementValue}
      </button>
    );
  }
}


const Result = (props) => {
	return (
  	<div>{props.counter}</div>
    );
};


class App extends React.Component {

	state = {counter: 0};

	incrementCounter = (incrementValue) => {
  	this.setState((prevState) => ({
    	counter: prevState.counter + incrementValue
    }));
  };
	
	render() {
  	return(
    	<div>
        <Button onClickFunction={this.incrementCounter} incrementValue={5}/>
        <Button onClickFunction={this.incrementCounter} incrementValue={15}/>
        <Button onClickFunction={this.incrementCounter} incrementValue={25}/>
        <Result counter={this.state.counter} />
      </div>
    );
  }
}


ReactDOM.render(<App />, mountNode)