Select Language Class

import 'package:flutter/material.dart';
import 'package:get/get.dart';
import 'package:user_ui/setting_screen.dart';
import 'package:shared_preferences/shared_preferences.dart';

class SelectLanguage extends StatefulWidget {
  const SelectLanguage({Key? key}) : super(key: key);

  @override
  State<SelectLanguage> createState() => _SelectLanguageState();
}

class _SelectLanguageState extends State<SelectLanguage> {
  String? selectedLanguage;
  Color textColor = Colors.black54;

  @override
  void initState() {
    super.initState();
    _loadSelectedLanguage();
  }

  // Load selected language from SharedPreferences
  void _loadSelectedLanguage() async {
    SharedPreferences prefs = await SharedPreferences.getInstance();
    setState(() {
      selectedLanguage = prefs.getString('selectedLanguage') ?? 'en_US';
      Get.updateLocale(Locale(selectedLanguage!.split('_')[0], selectedLanguage!.split('_')[1]));
    });
  }

  // Save selected language to SharedPreferences
  void _saveSelectedLanguage(String language) async {
    SharedPreferences prefs = await SharedPreferences.getInstance();
    await prefs.setString('selectedLanguage', language);
    Get.updateLocale(Locale(language.split('_')[0], language.split('_')[1]));
  }

  @override
  Widget build(BuildContext context) {
    final height = MediaQuery.of(context).size.height;
    final width = MediaQuery.of(context).size.width;

    return Scaffold(
      backgroundColor: Colors.white,
      appBar: AppBar(
        title: Text('selectLanguage'.tr, style: boldText),
        backgroundColor: Colors.white,
        leading: IconButton(
          onPressed: () {
            Navigator.of(context).pop(true);
          },
          icon: Icon(Icons.arrow_back_ios),
        ),
        titleSpacing: 0.0,
      ),
      body: Column(
        children: [
          SizedBox(
            height: height * 0.055,
            width: width,
            child: ListTile(
              title: Text(
                'english'.tr,
                style: semiBoldText.copyWith(
                  color: selectedLanguage == 'en_US' ? blue : textColor,
                  fontSize: height * 0.025,
                ),
              ),
              leading: Transform.scale(
                scale: 1.4,
                child: Radio<String>(
                  activeColor: blue,
                  value: 'en_US',
                  groupValue: selectedLanguage,
                  onChanged: (value) {
                    setState(() {
                      selectedLanguage = value;
                      _saveSelectedLanguage(value!);
                    });
                    Get.to(() =>
                        SettingScreen());
                  },
                ),
              ),
            ),
          ),
          SizedBox(
            height: height * 0.055,
            width: width,
            child: ListTile(
              title: Text(
                'hindi'.tr,
                style: semiBoldText.copyWith(
                  color: selectedLanguage == 'hi_IN' ? blue : textColor,
                  fontSize: height * 0.025,
                ),
              ),
              leading: Transform.scale(
                scale: 1.4,
                child: Radio<String>(
                  activeColor: blue,
                  value: 'hi_IN',
                  groupValue: selectedLanguage,
                  onChanged: (value) {
                    setState(() {
                      selectedLanguage = value;
                      _saveSelectedLanguage(value!);
                    });

                    Get.to(() =>
                        SettingScreen());
                  },
                ),
              ),
            ),
          ),
          SizedBox(
            height: height * 0.055,
            width: width,
            child: ListTile(
              title: Text(
                'marathi'.tr,
                style: semiBoldText.copyWith(
                  color: selectedLanguage == 'mr_IN' ? blue : textColor,
                  fontSize: height * 0.025,
                ),
              ),
              leading: Transform.scale(
                scale: 1.4,
                child: Radio<String>(
                  activeColor: blue,
                  value: 'mr_IN',
                  groupValue: selectedLanguage,
                  onChanged: (value) {
                    setState(() {
                      selectedLanguage = value;
                      _saveSelectedLanguage(value!);
                    });

                    Get.to(() =>
                        SettingScreen());
                  },
                ),
              ),
            ),
          ),
        ],
      ),
    );
  }
}

// Constants for text styles
const regulatText = TextStyle(fontFamily: 'Pangram', fontWeight: FontWeight.normal);
const semiBoldText = TextStyle(fontFamily: 'Pangram', fontWeight: FontWeight.w500);
const boldText = TextStyle(fontFamily: 'Pangram', fontWeight: FontWeight.bold);

// Color constants
Color blue = Color(0xFF027FFF);
Color red = Color(0xFFFF2121);
Color white = Colors.white;

in main.dart

import 'package:flutter/material.dart';
import 'package:get/get.dart';
import 'package:get/get_core/src/get_main.dart';

import 'package:suer_ui/utils/translations.dart';
 
import 'package:share_trick_ui/welcome_page.dart';
import 'package:shared_preferences/shared_preferences.dart';


// void main(){
void main() async{
  WidgetsFlutterBinding.ensureInitialized();

  // Load selected language from SharedPreferences
  SharedPreferences prefs = await SharedPreferences.getInstance();
  String selectedLanguage = prefs.getString('selectedLanguage') ?? 'en_US';

  // Set the locale based on the selected language
  Get.updateLocale(Locale(
    selectedLanguage.split('_')[0],
    selectedLanguage.split('_')[1],
  ));
  runApp(const MainScreen());
}
class MainScreen  extends StatelessWidget {
  const MainScreen({super.key});


  @override
  Widget build(BuildContext context) {

   // return   MaterialApp(
    return   GetMaterialApp(
      translations: AppTranslations(),
      locale: Get.deviceLocale, // Default locale based on device settings
      fallbackLocale: Locale('en', 'US'),
      debugShowCheckedModeBanner: false,
      home:  SplashScreen(),
    );
  }
}

App Translation

import 'package:get/get.dart';

class AppTranslations extends Translations {
  @override
  Map<String, Map<String, String>> get keys => {
    'en_US': {
      'selectLanguage': 'Select Language',
      'english': 'English',
      'hindi': 'Hindi',
      'marathi': 'Marathi',
      'setting': 'Settings',

    },
    'hi_IN': {
      'selectLanguage': 'भाषा चुनें',
      'english': 'अंग्रेज़ी',
      'hindi': 'हिन्दी',
      'marathi': 'मराठी',
      'setting': 'सेटिंग्स',
    },
    'mr_IN': {
      'selectLanguage': 'भाषा निवडा',
      'english': 'अंग्रेजी',
      'hindi': 'हिंदी',
      'marathi': 'मराठी',
      'setting': 'सेटिंग्ज',
    },
  };
}