import 'package:flutter/cupertino.dart';
import 'package:mobile.flutter.google_material.material2/google_material.dart';
 
void main() => runApp(MyApp());
 
class MyApp extends StatelessWidget {
  // This widget is the root of your application.
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Demo',
      home: WelcomScreenWidget()
    );
  }
}
 
class WelcomScreenWidget extends StatefulWidget {
  const WelcomScreenWidget({Key? key}) : super(key: key);
 
  @override
  State<WelcomScreenWidget> createState() => _WelcomScreenWidgetState();
}
 
class _WelcomScreenWidgetState extends State<WelcomScreenWidget> {
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      backgroundColor: Colors.grey,
      appBar: AppBar(
        title: Text("Welcome"),
      ),
      body: _buildCardNumberInputField(context, TextEditingController()),
    );
  }
 
  Widget _buildCardNumberInputField(
      BuildContext context,
      TextEditingController controller,
      ) {
    final textTheme = GoogleTextTheme.of(context);
    final cardNumberTextTheme =
    textTheme.gmBody1!;
 
    return Column(
      mainAxisSize: MainAxisSize.min,
      crossAxisAlignment: CrossAxisAlignment.start,
      children: [
        TextField(
          textAlign: TextAlign.left,
          style: cardNumberTextTheme,
          maxLines: 1,
          decoration: InputDecoration(
            fillColor: Colors.transparent,
            enabledBorder:  OutlineInputBorder(
              borderSide: BorderSide(color: Theme.of(context).dividerColor),
            ),
            focusedBorder:  OutlineInputBorder(
              borderSide: BorderSide(color: Theme.of(context).primaryColor, width: 2),
            ),
            labelText: "label text",
            labelStyle: cardNumberTextTheme,
            floatingLabelBehavior: FloatingLabelBehavior.never,
            hintText: "hint text",
            hintStyle: cardNumberTextTheme,
            prefixText: "prefix text",
            prefixStyle: cardNumberTextTheme,
          ),
          controller: controller,
          keyboardType: TextInputType.number,
        ),
    ]
    );
  }
}