Update Password In Flutter Firebase Authentication

 

1. using function

void _changePassword(String newpassword) async{
   //Create an instance of the current user. 
    FirebaseUser user = await FirebaseAuth.instance.currentUser();
   
    //Pass in the password to updatePassword.
    user.updatePassword(newpassword).then((_){
      print("Successfully changed password");
    }).catchError((error){
      print("Password can't be changed" + error.toString());
      //This might happen, when the wrong password is in, the user isn't found, or if the user hasn't logged in recently.
    });
  }

2. use of the firebase REST API way

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'},  
  )
}

You can get the idToken by using the getIdToken() method on the FirebaseUser object

You can get the firebase API key under the project setting in your console