Unable to run flutter mobile app due to null checker issue

Question

I'm trying to connect firebase to my flutter app. All the features are working fine, when running as a web app. But when I'm trying to run the mobile app, the app isn't running and showing an error message as below in the terminal.

E/flutter ( 4635): [ERROR:flutter/lib/ui/ui_dart_state.cc(199)] Unhandled Exception: Null check operator used on a null value
E/flutter ( 4635): #0      MethodChannel.binaryMessenger
package:flutter/…/services/platform_channel.dart:142
E/flutter ( 4635): #1      MethodChannel._invokeMethod
package:flutter/…/services/platform_channel.dart:148
E/flutter ( 4635): #2      MethodChannel.invokeMethod
package:flutter/…/services/platform_channel.dart:331
E/flutter ( 4635): #3      MethodChannel.invokeListMethod
package:flutter/…/services/platform_channel.dart:344

Below are the dependencies, I'm using:

environment:
  sdk: ">=2.7.0 <3.0.0"

dependencies:
  flutter:
    sdk: flutter
  firebase_core: "0.5.1"
  firebase_auth: "0.18.2"
  cloud_firestore: "0.14.2"

Below is my main.dart file

Future<void> main() async {
  await Firebase.initializeApp();
  runApp(new MaterialApp(
    home: Login(),
  ));
}

While running Flutter channel:

PS C:\Users\hp\Documents\firebase\blog_app> flutter channel
Flutter channels:
  master
  dev
  beta
* stable

Please post screenshot after running "flutter channel" command. Want to see if you are on a stable channel or any other — Taha Asif, Jun 13 '21 at 07:11
Also check if this helps: https://stackoverflow.com/questions/66712031/flutter-2-0-2-null-check-operator-used-on-a-null-value — Taha Asif, Jun 13 '21 at 07:14
@ProblematicDude there isn't any errors in the code I have written. It shows errors in the firebase.dart files - inbuilt fires of the firebase library — Thiluxan, Jun 13 '21 at 07:32
It's not your fault, actually. One of your package is messing things up. — Nikhil Badyal, Jun 13 '21 at 07:40
"Null check operator used on a null value" error also occurs when you are sending the wrong fields to firebase. For instance, one of the docs from firebase could be missing a field and that caused the null check operator to show itself. Therefore, double check if you are sending right fields. — Taha Asif, Jun 13 '21 at 07:52

Lakmal Fernando · Answer 1 · 2021-06-13T08:10:22.670

0

change your pubspec.yaml as follows.

environment:
  sdk: ">=2.7.0 <3.0.0"

dependencies:
  flutter:
    sdk: flutter
  firebase_core: ^1.3.0
  firebase_auth: ^1.4.1
  cloud_firestore: ^2.2.2

and run flutter put get in terminal

Then run flutter channel stable, flutter upgrade and flutter clean in terminal

edited Jun 13 '21 at 08:10

answered Jun 13 '21 at 07:13

Lakmal Fernando

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Unable to run flutter mobile app due to null checker issue

1 Answers1