main.dart

new Padding(
        padding: const EdgeInsets.only(top: 78.0),
        child: new Container(
          width: 302.0,
          child: new TextField(
            onChanged: (String text) => setState(() {
                  name = text;
                }),
            decoration: new InputDecoration(
                hintText: 'Enter your name',
                hintStyle: new TextStyle(color: Colors.white)),
          ),
  )),