title: How to set margin for a Button in Flutter
body: <p>I am just creating a form in Flutter. I am not able to set the top margin for the button.</p>
  
  <pre><code>class _MyHomePageState extends State&lt;MyHomePage&gt; {
  
  String firstname; 
  String lastname;
  final scaffoldKey = new GlobalKey&lt;ScaffoldState&gt;();
  final formKey = new GlobalKey&lt;FormState&gt;();
  
  
      @override
    Widget build(BuildContext context) {
      return new Scaffold(
        key: scaffoldKey,
        appBar: new AppBar(
          title: new Text('Validating forms'),
        ),
        body: new Padding(
          padding: const EdgeInsets.all(16.0),
          child: new Form(
            key: formKey,
            child: new Column(
              children: [
                new TextFormField(
                  decoration: new InputDecoration(labelText: 'First Name'),
                  validator: (val) =&gt;
                      val.length == 0 ?"Enter FirstName" : null,
                  onSaved: (val) =&gt; firstname = val,
                ),
                new TextFormField(
                  decoration: new InputDecoration(labelText: 'Password'),
                  validator: (val) =&gt;
                      val.length ==0 ? 'Enter LastName' : null,
                  onSaved: (val) =&gt; lastname = val,
                  obscureText: true,
                ),
                new RaisedButton(
                  onPressed: _submit,
                  child: new Text('Login'),
                ),
              ],
            ),
          ),
        ),
      );
    }
  </code></pre>