title: how to build Navigator() if use Getx?
body: <p>if we use <code>MaterialApp</code>, we build like this:</p>
  <pre><code>Navigator(
                  key: naviKey,
                  onGenerateRoute: (routeSettings) =&gt; MaterialPageRoute(
                    builder: (context)=&gt;Container(),
                  ),
                )
  </code></pre>
  <p>and now, how to build if we use <code>Getx</code>?</p>