content: import 'package:flutter/material.dart';
  import 'package:flutter_provider_architecture/ui/shared/text_styles.dart';
  import 'package:flutter_provider_architecture/ui/shared/ui_helpers.dart';
  
  class LoginHeader extends StatelessWidget {
    final TextEditingController controller;
    final String validationMessage;
  
    LoginHeader({@required this.controller, this.validationMessage});
  
    @override
    Widget build(BuildContext context) {
      return Column(children: <Widget>[
        Text('Login', style: headerStyle),
        UIHelper.verticalSpaceMedium(),
        Text('Enter a number between 1 - 10', style: subHeaderStyle),
        LoginTextField(controller),
        this.validationMessage != null
            ? Text(validationMessage, style: TextStyle(color: Colors.red))
            : Container()
      ]);
    }
  }
  
  class LoginTextField extends StatelessWidget {
    final TextEditingController controller;
  
    LoginTextField(this.controller);
  
    @override
    Widget build(BuildContext context) {
      return Container(
        padding: EdgeInsets.symmetric(horizontal: 15.0),
        margin: EdgeInsets.symmetric(horizontal: 15.0, vertical: 15.0),
        height: 50.0,
        alignment: Alignment.centerLeft,
        decoration: BoxDecoration(
            color: Colors.white, borderRadius: BorderRadius.circular(10.0)),
        child: TextField(
            decoration: InputDecoration.collapsed(hintText: 'User Id'),
            controller: controller),
      );
    }
  }
  