Flutter - Changing the color of the appbar is not working

Question

I am trying to change the background color of AppBar but it is not working.

When choosing the color 0x673AB7 according to the image below, AppBar turns gray instead of purple.

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),
      ),
    );
  }
}

Answer 1

It looks like your color is completely transparent. Try changing the color to 0xFF673AB7