Category "dart-null-safety"

Flutter - The non-nullable local variable 'newTaskTitle' must be assigned before it can be used

Hi so I have been getting this error - "The non-nullable local variable 'newTaskTitle' must be assigned before it can be used. (Documentation) Try giving it an

Exception: Context is null, please call ToastContext.init(context) first

The issue is seen on the Toast.dart and Armodel.dart. if possible please suggest me how do i implement OCR as i followed up the codes from Pubdev but still when

Error: The parameter 'scaffoldKey' can't have a value of 'null' [...] 'GlobalKey<ScaffoldState>'

When trying to run the function below, you get this error: home page import 'package:flutter/material.dart'; import 'package:provider/provider.dart'; import '..

Flutter null safety plugin_platform_interface

I have this error, Error: Cannot run with sound null safety, because the following dependencies don't support null safety: - package:plugin_platform_interface

Argument type 'String?' cannot be assigned to parameter type 'String', Triggering Dart's Null Safety either way

In this current snippet I have declared notification to be nullable but get an null safe error for the if loop's notification.body and notification.title. Here'

Is there a way of assigning a future variable to another variable without returning null in dart?

I was trying to pass a data to a variable that returns future but it returns out to be null even though I'm using async and await. what is I'm missing here ? im

Non-nullable instance field must be initialized

class Foo { int count; // Error void bar() => count = 0; } Why I'm seeing an error when I'am already initializing it in the bar method? I could understa

Notification channel 'basic_channel' does not exist., n.a.a.k.f.a:

As per flutter package I implemented code on my project but it threw exception while making build, "Notification channel 'call_channel' does not exist., n.a.a.k

The method '[]' was called on null. Receiver: null Tried calling: []("main") console error

Hi i am working on a weather app i learnt from a course, everything was working fine till i start with the refactoring and it just got complicated the code show

"Bad state: Cannot call `when` within a stub response", "type 'Null' is not a subtype of type [...]"

I wrote a few unit and widget tests for my Flutter app. They all pass when called from the testing window out of VSCode: But when I call flutter test from the

Flutter: Unable to migrate to null safety

I am following this guide to migrate my project to null safety: https://dart.dev/null-safety/migration-guide But I am facing this issue with the dart migrate co

Can anyone please explain the use of null-shorting cascade in Dart?

I'm confused about what the documentation says here:

How is Dart "sound null-safety" different from Kotlin null safety?

This Dart official video states that Dart's so-called "sound null safety" is better than Kotlin's null safety design, because it can optimise the code based on

Null safety migration error: package has unmigrated dependencies. But all my dependencies declare support for null-safety

Im trying to migrate dart null safety but I get the following error when I run dart migrate Bad state: Error: package has unmigrated dependencies. Before migra

The parameter can't have a value of 'null' because of its type in Dart

Dart function I have the following Dart function and I am now using null safety: void calculate({int factor}) { // ... } The analyzer complains that: The pa

The argument type 'Function?' can't be assigned to the parameter type 'void Function()?'

I have a refactored widget which has an onPressed. But whenever I try to access that function, I get this error : The argument type Function? can't be assigned

Dart: Custom "copyWith" method with nullable properties

I'm trying to create a "copyWith" method for my class, and it works with most scenarios. The problem is when I try to set a nullable property to null, because m

The argument type 'List<DropdownMenuItem<dynamic>>' can't be assigned to the parameter type 'List<DropdownMenuItem<String>>?

Currently, I am working on a Flutter tutorial which was developed on previous versions. The error occurred once we updated to the latest version of Dart and Flu

How to implement null-safety in simple flutter-dart code with object snapshot.data?

I am new to flutter/dart coding, please help me solve the following: Here is my code trying to fetch data from the FireStore collection "DinnerNames" but I get

I want to Save Contact Number at Mobile storage using Flutter

I wrote this function to save contact number, but it can't save on local storage Future _saveContact() async { Contact contact = Contact(); contact.fami

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