title: How to set Flutter app theme as to dark by default?
body: <p>I've created a simple login UI in flutter, but I don't know how to make the overall theme of the app as dark. What I mean is that in the future, if I add more functionality to the app, it should all be in the dark theme. Is there any way to do that?</p>
  
  <p>I've used a separate dart file (login.dart) and all the widgets used in my login UI are in this file. I've set the ThemeData as dark in the main dart file (main.dart), but the app is still running in light theme.</p>
  
  <p>Here's my code:</p>
  
  <p><strong>main.dart</strong></p>
  
  <pre><code>import 'package:flutter/material.dart';
  import 'package:bidder_login/login.dart';
  
  void main(){
      runApp(
          MaterialApp(
        theme: ThemeData(),
        darkTheme: ThemeData.dark(),
              debugShowCheckedModeBanner: false,
              title: "Basic Login Demo",
              home: LoginPage(),
          ),
      );
  }
  </code></pre>
  
  <p><strong>login.dart</strong></p>
  
  <pre><code>import 'package:flutter/material.dart';
  
  class LoginPage extends StatefulWidget {
      @override
      _LoginPageState createState() =&gt; _LoginPageState();
  }
  
  class _LoginPageState extends State&lt;LoginPage&gt; {
      @override
      Widget build(BuildContext context) {
          return Scaffold(
              body: SafeArea(
                  child: ListView(
                      padding: EdgeInsets.symmetric(horizontal: 24.0),
                      children: &lt;Widget&gt;[
                          SizedBox(height: 80.0),
                          // Column(
                          //  children: &lt;Widget&gt;[
                          //      Image.asset('assets/login_app.png'),
                          //      SizedBox(height: 25.0),
                          //      Text("Material Login"),
                          //  ],
                          // ),
  
                          //*Username starts here
                          SizedBox(height: 120.0),
                          TextField(
                              decoration: InputDecoration(
                                  labelText: 'Username',
                                  filled: true,
                              ),
                          ),
  
                          //*Password starts here
                          SizedBox(height: 12.0),
                          TextField(
                              decoration: InputDecoration(
                                  labelText: 'Password',
                                  filled: true,
                              ),
                              obscureText: true,
                          ),
                          ButtonBar(
                              children: &lt;Widget&gt;[
                                  FlatButton(
                                      child: Text('Cancel'),
                                      onPressed: () {
  
                                      },
                                  ),
                                  RaisedButton(
                                      child: Text('Next'),
                                      onPressed: () {
  
                                      },
                                  )
                              ],
                          )
  
                      ],
                  ),
              ),
          );
      }
  }
  </code></pre>