flutter-examples/firebase_todo_app/lib/Signin.dart

import 'package:firebase_auth/firebase_auth.dart' as firebase_auth;
import 'package:flutter/material.dart';
import 'package:get/get.dart';
import 'package:github.nisrulz.todo_app/Home.dart';
import 'package:github.nisrulz.todo_app/Signup.dart';

class Signin extends StatefulWidget {
  const Signin({super.key});

  @override
  State<Signin> createState() => _SigninState();
}

class _SigninState extends State<Signin> {
  firebase_auth.FirebaseAuth firebaseauth = firebase_auth.FirebaseAuth.instance;
  final TextEditingController _emailcontroller = TextEditingController();
  final TextEditingController _passwordcontroller = TextEditingController();

  @override
  void dispose() {
    _emailcontroller.dispose();
    _passwordcontroller.dispose();
    super.dispose();
  }

  Future<void> _Signin() async {
    try {
      final String email = _emailcontroller.text;
      final String password = _passwordcontroller.text;

      await firebaseauth.signInWithEmailAndPassword(
        email: email,
        password: password,
      );

      Get.snackbar(
        "Sign In Success",
        "You have successfully signed in.",
        backgroundColor: Colors.green,
        snackPosition: SnackPosition.BOTTOM,
        duration: Duration(seconds: 3),
      );

      Get.to(() => HomePage());
    } catch (e) {
      Get.snackbar(
        "Sign In Error",
        e.toString(),
        backgroundColor: Colors.red,
        snackPosition: SnackPosition.BOTTOM,
        duration: Duration(seconds: 3),
      );
    }
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: SingleChildScrollView(
        child: Container(
          height: Get.size.height,
          width: Get.size.width,
          color: Colors.black,
          child: Column(
            mainAxisAlignment: MainAxisAlignment.center,
            children: [
              const Text(
                "Login ",
                style: TextStyle(
                    color: Colors.green,
                    fontSize: 25,
                    fontWeight: FontWeight.bold),
              ),
              const SizedBox(height: 20),
              const SizedBox(height: 20),
              SizedBox(
                height: 20,
              ),
              SizedBox(height: 20),
              Container(
                width: Get.size.width - 60,
                height: 60,
                child: Card(
                  child: Padding(
                    padding: EdgeInsets.symmetric(horizontal: 16.0),
                    child: Center(
                      child: TextField(
                        controller: _emailcontroller,
                        decoration: InputDecoration(
                          hintText: 'Email',
                          border: InputBorder.none,
                        ),
                      ),
                    ),
                  ),
                ),
              ),
              SizedBox(height: 20),
              Container(
                width: Get.size.width - 60,
                height: 60,
                child: Card(
                  child: Padding(
                    padding: EdgeInsets.symmetric(horizontal: 16.0),
                    child: Center(
                      child: TextField(
                        controller: _passwordcontroller,
                        obscureText: true,
                        decoration: InputDecoration(
                          hintText: 'Password',
                          border: InputBorder.none,
                        ),
                      ),
                    ),
                  ),
                ),
              ),
              SizedBox(height: 20),
              ElevatedButton(
                onPressed: _Signin,
                child: Text("Sign In"),
              ),
              SizedBox(height: 20),
              GestureDetector(
                onTap: () {
                  Get.to(() => Signup());
                },
                child: const Text(
                  "Don't have an account? Sign Up",
                  style: TextStyle(
                      color: Colors.white,
                      decoration: TextDecoration.underline,
                      fontSize: 18),
                ),
              ),
            ],
          ),
        ),
      ),
    );
  }
}