The named Parameters are not defined error

Question

Here is my code ,it is showing errors like The named parameter 'accentColor' isn't defined.Try correcting the name to an existing named parameter's name, or defining a named parameter with the name 'accentColor'.and the same with parameter 'brightness'.

  import 'package:flutter/material.dart';
    // import 'package:rangkings/config/config.dart';    
    // import '../config/config.dart';
    
    class ThemeModel {
      final lightMode = ThemeData(
        primarySwatch: Colors.blue,
        primaryColor: Color(0xFF3A52BC),
        accentColor: Colors.white,
        iconTheme: IconThemeData(color: Colors.white),
        fontFamily: 'Manrope',
        scaffoldBackgroundColor: Colors.white,
        brightness: Brightness.light,
        primaryColorDark: Colors.grey[800],
        primaryColorLight: Colors.white,
        secondaryHeaderColor: Colors.grey[600],
        shadowColor: Colors.grey[200],
        backgroundColor: Colors.white,
        appBarTheme: AppBarTheme(
          brightness: Brightness.light,
          color: Color(0xFF3A52BC),
          elevation: 0,
          iconTheme: IconThemeData(
            // color: Colors.grey[900],
            color: Colors.white,
          ),
          actionsIconTheme: IconThemeData(color: Colors.grey[900]),
          // textTheme: TextTheme(
          //   headline6: TextStyle(
          //     fontFamily: 'Manrope',
          //     fontSize: 18,
          //     fontWeight: FontWeight.w700,
          //     // color: Colors.grey[900],
          //     color: Colors.white,
          //   ),
          // ),
        ),
        textTheme: TextTheme(
          subtitle1: TextStyle(
              fontWeight: FontWeight.w500, fontSize: 16, color: Colors.grey[900]),
          bodyText2: TextStyle(
              fontWeight: FontWeight.w500, fontSize: 16, color: Colors.grey[900]),
        ),
        bottomNavigationBarTheme: BottomNavigationBarThemeData(
          backgroundColor: Colors.white,
          selectedItemColor: Color(0xFF3A52BC),
          unselectedItemColor: Colors.grey[500],
        ),
      );
    
      final darkMode = ThemeData(
          primarySwatch: Colors.deepPurple,
          primaryColor: Color(0xFF3A52BC),
          accentColor: Colors.white,
          iconTheme: IconThemeData(color: Colors.white),
          fontFamily: 'Manrope',
          scaffoldBackgroundColor: Color(0xff303030),
          brightness: Brightness.dark,
          primaryColorDark: Colors.grey[300],
          primaryColorLight: Colors.grey[800],
          secondaryHeaderColor: Colors.grey[400],
          shadowColor: Color(0xff282828),
          backgroundColor: Colors.grey[900],
          appBarTheme: AppBarTheme(
            brightness: Brightness.dark,
            color: Colors.grey[900],
            elevation: 0,
            iconTheme: IconThemeData(
              color: Colors.white,
            ),
            actionsIconTheme: IconThemeData(color: Colors.white),
            // textTheme: TextTheme(
            //   headline6: TextStyle(
            //     fontFamily: 'Manrope',
            //     fontSize: 18,
            //     fontWeight: FontWeight.w700,
            //     color: Colors.white,
            //   ),
            // ),
          ),
          textTheme: TextTheme(
            subtitle1: TextStyle(
                fontWeight: FontWeight.w500, fontSize: 16, color: Colors.white),
          ),
          bottomNavigationBarTheme: BottomNavigationBarThemeData(
            backgroundColor: Colors.grey[900],
            selectedItemColor: Colors.white,
            unselectedItemColor: Colors.grey[500],
          ));
    }

Give an efficient solution for this errors,only those 4 errors are showing 2 accentColor one's and 2 brightness.

Answer 1

Both accentColor and brightness are deprecated, use colorScheme.secondary to replace accentColor, and systemOverlayStyle to replace brightness.