Answers for "flutter save password"

show password in flutter

TextFormField(
   keyboardType: TextInputType.text,
   controller: _userPasswordController,
   obscureText: !_passwordVisible,//This will obscure text dynamically
   decoration: InputDecoration(
       labelText: 'Password',
       hintText: 'Enter your password',
       // Here is key idea
       suffixIcon: IconButton(
            icon: Icon(
              // Based on passwordVisible state choose the icon
               _passwordVisible
               ? Icons.visibility
               : Icons.visibility_off,
               color: Theme.of(context).primaryColorDark,
               ),
            onPressed: () {
               // Update the state i.e. toogle the state of passwordVisible variable
               setState(() {
                   _passwordVisible = !_passwordVisible;
               });
             },
            ),
          ),
        );

show password in flutter

@override
  void initState() {
    _passwordVisible = false;
  }

change password firebase flutter

import 'package:http/http.dart' as http;
import 'dart:convert';
import 'dart:async';

Future<Null> changePassword(String newPassword) async {
  const String API_KEY = 'YOUR_API_KEY';
  final String changePasswordUrl =
      'https://www.googleapis.com/identitytoolkit/v3/relyingparty/setAccountInfo?key=$API_KEY';

      final String idToken = await user.getIdToken(); // where user is FirebaseUser user

    final Map<String, dynamic> payload = {
      'email': idToken,
      'password': newPassword,
      'returnSecureToken': true
    };

  await http.post(changePasswordUrl, 
    body: json.encode(payload), 
    headers: {'Content-Type': 'application/json'},  
  )
}