ReactJS

Quiz

Text

Text

ReactJS

ReactJS in a Nutshell

  • The V in MVC
  • Declarative
  • Everything is a Component
  • 1-Way-Dataflow

Components

Components

Components

Components

Components

class SearchBar extends React.Component {
  render() {
    return (
      <form>
        <input type="text" placeholder="Search..." />
        <p>
          <input type="checkbox" />
          {' '}
          Only show products in stock
        </p>
      </form>
    );
  }
}
class SearchBar extends React.Component {
  render() {










  }
}

Components

class FilterableProductTable extends React.Component {
  render() {
    return (
      <div>
        <SearchBar />
        <ProductTable products={this.props.products} />
      </div>
    );
  }
}

JSX

  • Html extension to JavaScript
  • Optional
  • Can be combined with JS
  • Html linting
  • Feels like html (but isn't)

State

State

  • stuffThatShouldBeForgottenIfTheUserRefreshes
  • Belongs to component
  • this.state
  • Try to have as little state as possible
  • Don't duplicate - calculate

State

class HelloState extends React.Component {

  constructor() {
    this.state = {
      count: 0
    };
  }

  render() {
    return (
      <div>
        Count: {this.state.count}
      </div>
    );
  }
}
class HelloState extends React.Component {

  constructor() {
    this.state = {
      count: 0
    };
  }

  increment() {
    this.setState({
      count: this.state.count + 1
    });
  }

  render() {
    return (
      <div>
        Count: {this.state.count}

        <button onClick={this.increment}>Add 1</button>
      </div>
    );
  }
}
// index.html

<script>
  function increment() {
    let element = $('#count');
    let current = element.text();
    element.text(parseInt(current) + 1);
  }
</script>


<div>
  Count: <label id="count">0</label>

  <button onclick="increment()">Add 1</button>
</div>

With jQuery...

Props

  • stuffThatShouldStayTheSameIfTheUserRefreshes
  • this.props
  • read only
<todo-item title="Buy milk" color={this.state.defaultColor}>

Should I start using ReactJS?

  • Easy to learn
  • 1-Way-Dataflow helps to reduce complexity
  • Many third party components
  • Overhead
  • Problematic License

Advanced State Management

Flux

React beyond the Browser

React Native

Server Side Rendering

React beyond React...

Links

ReactJS

By Michael Müller

ReactJS

  • 637