NosuchMethodError: The getter '_value' was called on null

[boomitsocial]

Hello,
So our app was deployed on PlayStore & AppStore in June. We haven't updated it since. Everything was working well, but suddenly we started getting this error on or chat-room/list page. We know we haven't upgraded our flutter (it's taking more time due to many many breaking changes and our team can only work on this on weekends).
So now out of the blue, two very important screens of our live app is down. Any help in solving or tracking down this issue will be appreciated.

> [√] Flutter (Channel dev, v0.11.9, on Microsoft Windows [Version 10.0.18362.356], locale en-IN)
    • Flutter version 0.11.9 at C:\src\flutter
    • Framework revision d48e6e433c (11 months ago), 2018-11-20 22:05:23 -0500
    • Engine revision 5c8147450d
    • Dart version 2.1.0 (build 2.1.0-dev.9.4 f9ebf21297)

>[!] Android toolchain - develop for Android devices (Android SDK 28.0.3)
    • Android SDK at C:\Users\bhavi\AppData\Local\Android\sdk
    • Android NDK location not configured (optional; useful for native profiling support)
    • Platform android-29, build-tools 28.0.3
    • Java binary at: C:\Program Files\Android\Android Studio\jre\bin\java
    • Java version OpenJDK Runtime Environment (build 1.8.0_202-release-1483-b03)
    X Android license status unknown.

>[√] Android Studio (version 3.5)
    • Android Studio at C:\Program Files\Android\Android Studio
    • Flutter plugin version 38.2.3
    • Dart plugin version 191.8423
    • Java version OpenJDK Runtime Environment (build 1.8.0_202-release-1483-b03)

>[√] VS Code (version 1.38.1)
    • VS Code at C:\Users\bhavi\AppData\Local\Programs\Microsoft VS Code
    • Flutter extension version 3.4.1

[√] Connected device (1 available)
    • SM N9208 • 11160b2925d22e02 • android-arm64 • Android 7.0 (API 24)
Attaching the stack trace from flutter run
[stack.txt](https://github.com/flutter/flutter/files/3684870/stack.txt)

The rest of the app works fine (all screens open, connects to our api and calls data, etc.) in fact we can even click on 'New Message' and are able to successfully send a message to a contact.
The only thing not working, as mentioned earlier, is the UI of chat list/chat room list page (Chats & Plans)

[janmoppel]

Hello @boomitsocial !

Thank you for posting an issue.

It seems like that similar behaviour was reported and discussed here before: https://stackoverflow.com/questions/54415836/nosuchmethoderror-the-getter-value-was-called-on-null-populating-list-of-d

Can you please provide more information for reproducing the issue. E.g. small self-contained application with the similar logic as in the chat room list page. As from the first look at your issue and attached StackOverflow discussion, it doesn't seem like there is a problem in the Flutter itself.

Thank you.

[escamoteur]

May I add, please enable 'Break on all Exeptions' in your debugger? Then you get a full stacktrace when this happens.
This stacktrace would be important for us.
But you are on a really really old Flutter version so I recommend doing the upgrade.

[boomitsocial]

Hello, so after literally going through almost every line of code, we found the issue.
Instead of
if ( messageDateTime.month < 10 ){ if ( messageDateTime.day < 10 ){ messageDateTime = DateTime.parse("${messageDateTime.year}-0${messageDateTime.month}-0${messageDateTime.day} 00:00:00"); } else { messageDateTime = DateTime.parse("${messageDateTime.year}-0${messageDateTime.month}-${messageDateTime.day} 00:00:00"); }
we did
if ( messageDateTime.month < 10 ){ if ( messageDateTime.day < 10 ){ messageDate = DateTime.parse("${messageDateTime.year}-0${messageDateTime.month}-0${messageDateTime.day} 00:00:00"); } else { messageDate = DateTime.parse("${messageDateTime.year}-0${messageDateTime.month}-${messageDateTime.day} 00:00:00"); }
Really small mistake, but just wanted to say that, sometimes it's not flutter, plugins or apis, its just a small mistake :)

[github-actions]

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