learning-redux-Counter.js

import React, { Component } from 'react'

export default class Counter extends Component {
  state = { 
    count: 0 
  }

  increment = () => {
    this.setState({
      count: this.state.count + 1
    })
  }
  
  decrement = () => {
    this.setState({
      count: this.state.count - 1
    })
  }
  
  render() {
    return (
      <div>
        <h2>Counter</h2>
        <div>
          <button onClick={this.decrement}>-</button>
          <span>{this.state.count}</span>
          <button onClick={this.increment}>+</button>
        </div>
      </div>
    )
  }
}