In the drawer, I’m showing the user’s email address. but null error is showing ! i am also adding ? this sign same error but null final email = FirebaseAuth.instance.currentUser!.email; Center( child: Text( ‘$email’, style: const TextStyle(fontWeight: FontWeight.bold, fontSize: 18.0, color: Colors.indigo), ), ), >Solution : It is possible your currentUser is null. Instead of… Read More Null check operator used on a null value in flutter project

I have been trying to update a Map<String, List> sender like I would a normal map, and I haven’t had any luck. I looked at this question but trying to add a [0] to mark the index doesn’t work. I keep getting a Script error so when the list isn’t even being displayed in my… Read More how to update a list used as a value for a map in dart

My code works fine last week, then when the credentials expire, i recreate another credentials and replace the credentials, now the code doesnt work anymore and show the error [ERROR:flutter/runtime/dart_vm_initializer.cc(41)] Unhandled Exception: LateInitializationError: Field ‘dialogflow’ has not been initialized. import ‘package:dialogflow_grpc/dialogflow_grpc.dart’; import ‘package:dialogflow_grpc/generated/google/cloud/dialogflow/v2beta1/session.pb.dart’; import ‘dart:async’; import ‘package:flutter/material.dart’; import ‘package:flutter/services.dart’; class Chat extends StatefulWidget { Chat({Key?… Read More LateInitializationError: Field 'dialogflow' has not been initialized

I’m getting the following error after building my flutter app after i run the flutter run: type ‘Null’ is not a subtype of type ‘String’ in type cast The trace that is observed is as follows : I/flutter ( 8093): type ‘Null’ is not a subtype of type ‘String’ in type cast I/flutter ( 8093):… Read More Flutter:type 'Null' is not a subtype of type 'String' in type cast

The function can’t be unconditionally invoked because it can be ‘null’. getting an error in this part auth.currentUser FirebaseAuth auth = FirebaseAuth.instance; final User user = await auth.currentUser(); String uid = user.uid; await FirebaseFirestore.instance.collection(‘data’).doc(uid).collection(‘data’).doc(); >Solution : try; FirebaseAuth auth = FirebaseAuth.instance; final User user = await auth.currentUser; String uid = user!.uid; await FirebaseFirestore.instance.collection(‘data’).doc(uid).collection(‘data’).doc();

I am trying to make an app which takes names then validates it. I got which says : The operator ‘+’ can’t be unconditionally invoked because the receiver can be ‘null’. I tried to write ‘ if (value != null), but then i got another error. Expanded( child: ListView.builder( itemCount: animeler.length, itemBuilder: (BuildContext context, int… Read More Operator '+' cannot be called on 'String?' because it is potentially null. In Flutter

I’m new to Flutter darts development and trying to learn. I want to create a model with a constructor, one of which contains a field of type DateTime which is optional. I tried by making it like this: import ‘package:equatable/equatable.dart’; class Customer extends Equatable { final int indexs; final DateTime apply_date; Customer({ required this.indexs, this.apply_date,… Read More How to make optional datetime parameter in flutter dart with null safety

I’m trying to pass a function as default value of an optional parameter, but it gives me the followig error "The default value of an optional parameter must be constant" class ElevatedBtn extends StatelessWidget { final String text; final color, width, height, onTap; const ElevatedBtn( {super.key, required this.text, this.color, this.width, this.height, this.onTap=(){} } ); }… Read More Passing function as default value of an optional parameter

I am creating a drawer in flutter but whenever I click on the menu to open it, I get a Null check operator used on a null value error. What could be wrong? final scaffoldKey = GlobalKey<ScaffoldState>(); // the scaffoldKay variable AppBar( leading: IconButton( onPressed: () { scaffoldKey.currentState!.openDrawer(); // Error Here }, icon: Icon( Icons.menu,… Read More Null Check Operator used on null value – flutter

I am trying to implement such logic in slider: i want to pull data from a map which looks like this: {min: 1, max: 16, value: 1.0, step: 1.0}. This data comes from API and I want to manipulate the slider with this data. I did it like in code below, but nothing has happend:… Read More how to make slider in flutter with API data?