Illustrate component behavior in App.js

src/App.js

@@ -4,17 +4,30 @@ import './App.css';
 import LoadingIndicator from './components/LoadingIndicator';
 
 class App extends Component {
+  state = {
+    isLoading: true,
+  };
+
+  componentWillMount() {
+    this._timer = setTimeout(
+      () => this.setState({isLoading: false}),
+      2000
+    );
+  }
+
+  componentWillUnmount() {
+    clearTimeout(this._timer);
+  }
+
   render() {
     return (
       <div className="App">
         <header className="App-header">
           <img src={logo} className="App-logo" alt="logo" />
           <h1 className="App-title">Welcome to React</h1>
         </header>
-        <p className="App-intro">
-          To get started, edit <code>src/App.js</code> and save to reload.
-        </p>
-        <LoadingIndicator isLoading={false}>
+        <pre>isLoading: {String(this.state.isLoading)}</pre>
+        <LoadingIndicator isLoading={this.state.isLoading}>
           <div>ahoy!</div>
         </LoadingIndicator>
       </div>