title: Flutter - Changing the color of the appbar is not working
body: <p>I am trying to change the background color of AppBar but it is not working.</p>
  
  <p>When choosing the color <code>0x673AB7</code> according to the image below, AppBar turns gray instead of purple.</p>
  
  <pre><code>import "package:flutter/material.dart";
  
  void main() {
    runApp(new ControlleApp());
  }
  
  class ControlleApp extends StatelessWidget {
    @override
    Widget build(BuildContext context) {
      return new MaterialApp(
        title: "Controlle Financeiro",
        home: new HomePage(),
      );
    }
  }
  
  class HomePage extends StatelessWidget {
    @override
    Widget build(BuildContext context) {
      return new Scaffold(
        appBar: new AppBar(
          backgroundColor: new Color(0x673AB7),
        ),
      );
    }
  }
  </code></pre>
  
  <p><a href="https://i.stack.imgur.com/2tiIL.png" rel="noreferrer"><img src="https://i.stack.imgur.com/2tiIL.png" alt="enter image description here"></a></p>