React Context API

by nabendu

HTML

<div id="app"></div>

CSS

body {
  background: #20262E;
  padding: 20px;
  font-family: Helvetica;
}

#app {
  background: #fff;
  border-radius: 4px;
  padding: 20px;
  transition: all 0.2s;
}

li {
  margin: 8px 0;
}

h2 {
  font-weight: bold;
  margin-bottom: 15px;
}

.done {
  color: rgba(0, 0, 0, 0.3);
  text-decoration: line-through;
}

input {
  margin-right: 5px;
}

React

const FamilyContext = React.createContext({});

class GrandFather extends React.Component {
  state = {
    lastName: "Biswas"
  };

  render() {
    return (
      <FamilyContext.Provider value={this.state.lastName}>
        <Father />
      </FamilyContext.Provider>
    );
  }
}


const Father = () => {
  return <Child />;
};

const Child = () => {
  return <FamilyContext.Consumer>{context => <p>{context}</p>}</FamilyContext.Consumer>;
};

ReactDOM.render(<GrandFather />, document.querySelector("#app"))