Import directive in ionic2 - ng2-qrcode
<p>I trying use the <strong>ng2-qrcode</strong> in my test <strong>ionic2</strong> app, but this never found the directive, follow the <code>ionic serve</code> output:</p>

<blockquote>
  <p>serve  /?restart=454981  (www/index.html) serve  /cordova.js  (mocked)
  serve  /build/js/es6-shim.min.js serve  /build/js/Reflect.js serve 
  /build/js/zone.js serve  /build/js/app.bundle.js serve 
  /build/css/app.md.css serve  /build/app.html serve 
  /build/pages/page1/page1.html 0     045123   log      Angular 2 is
  running in the development mode. Call enableProdMode() to enable the
  production mode. 1     045125   warn     Native: tried calling
  StatusBar.styleDefault, but Cordova is not available. Make sure to
  include cordova.js or run in a device/simulator 2     045159   group<br>
  EXCEPTION: Error: Uncaught (in promise): No Directive annotation found
  on QRCodeComponent 3     045160   error    EXCEPTION: Error: Uncaught
  (in promise): No Directive annotation found on QRCodeComponent 4<br>
  045160   error    STACKTRACE: 5     045161   error<br>
  resolvePromise@<a href="http://localhost:8100/build/js/zone.js:538:32" rel="nofollow">http://localhost:8100/build/js/zone.js:538:32</a>
  resolvePromise@<a href="http://localhost:8100/build/js/zone.js:523:18" rel="nofollow">http://localhost:8100/build/js/zone.js:523:18</a>
  scheduleResolveOrReject/&lt;@<a href="http://localhost:8100/build/js/zone.js:571:18" rel="nofollow">http://localhost:8100/build/js/zone.js:571:18</a>
  Zonehttp://localhost:8100/build/js/zone.js:356:24
  NgZoneImpl/this.inner&lt;.onInvokeTask@<a href="http://localhost:8100/build/js/app.bundle.js:35178:32" rel="nofollow">http://localhost:8100/build/js/app.bundle.js:35178:32</a>
  Zonehttp://localhost:8100/build/js/zone.js:355:24
  Zonehttp://localhost:8100/build/js/zone.js:256:29
  drainMicroTaskQueue@<a href="http://localhost:8100/build/js/zone.js:474:26" rel="nofollow">http://localhost:8100/build/js/zone.js:474:26</a>
  ZoneTask/this.invoke@<a href="http://localhost:8100/build/js/zone.js:426:22" rel="nofollow">http://localhost:8100/build/js/zone.js:426:22</a></p>
  
  <p>6     045161   groupEnd  7     045162   error    Unhandled Promise
  rejection:, No Directive annotation found on QRCodeComponent, ; Zone:,
  angular, ; Task:, Promise.then, ; Value:, [object Object]</p>
</blockquote>

<p>I follow the <a href="https://github.com/PragmaticClub/ng2-qrcode" rel="nofollow">readme</a> on GitHub and do:</p>

<blockquote>
  <p>npm install ng2-qrcode</p>
</blockquote>

<p>Create a Class with component annotation:</p>

<pre><code>import { Component } from '@angular/core';
import { NavController, NavParams } from 'ionic-angular';
import {QRCodeComponent} from 'ng2-qrcode'

@Component({
  templateUrl: 'build/pages/page1/page1.html',
  directives: [QRCodeComponent],
})
export class Page1
{
  constructor(private navCtrl: NavController ) { }
}
</code></pre>

<p>And put the tag in template <strong>build/pages/page1/page1.html</strong>:</p>

<pre><code>&lt;qrcode qrdata="'My QR code data string'" size="256" level="'M'"&gt;&lt;/qrcode&gt;
</code></pre>

<p>But I'm getting this error, what is wrong? Is hard do find Ionic2 explanations or documentations and I'm very beginner in Ionic2 and typescript.</p>