FilePicker reports NPE crashes in Google Play Console

[Arcturus5404]

Describe the bug
Google Play Console reports the following:

java.lang.NullPointerException

java.lang.NullPointerException: 
  at com.mr.flutter.plugin.filepicker.FilePickerDelegate$2.run (FilePickerDelegate.java:128)
  at java.lang.Thread.run (Thread.java:919)

Issue details

1. Platform Android
2. Detailed steps to reproduce:
   I currently have no way to reproduce this issue. It works on all emulators I have tested, so I have no idea how serious this problem is.

Error Log
None

Screenshots and/or video
None

Flutter Version details
flutter --version
Flutter 1.20.4 • channel stable • https://github.com/flutter/flutter.git
Framework • revision fba99f6cf9 (3 days ago) • 2020-09-14 15:32:52 -0700
Engine • revision d1bc06f032
Tools • Dart 2.9.2

Additional context
Version

• file_picker 2.0.0

[miguelpruivo]

@Arcturus5404 hi! Thank you for reporting.

This is quite odd actually, it’s throwing a null pointer on an array method in a place where it can’t ever be null (a few lines before it’s instanciated). Could you please post full stack trace?

Thank you!

[Arcturus5404]

That's all I have in Google Play Console I'm afraid..

One other interesting detail: I have 12 crash reports
11 on Samsung Galaxy A10e Android 10 (SDK 29)
1 on LGE QStylus Android 8.1 (SDK 27)

Not sure of that is of any matter of that its just 1 user trying several times in case of Samsung

EDIT Huawei was on an old version, hence the edit!

[Arcturus5404]

[Arcturus5404]

I checked your file as well.. can never be null.. is there something weird with my code perhaps?

I use one for images:

FilePickerResult images =
                          await FilePicker.platform.pickFiles(type: FileType.image, allowMultiple: true);

                      if (images != null && images.paths.isNotEmpty) {
                        List<File> files = images.paths.map((path) => File(path)).toList();
                        setState(() => _stream = chooseAttachments(files));
                      }

and one for PDFs:

FilePickerResult pdfs = await FilePicker.platform.pickFiles(
                       allowMultiple: true,
                       type: FileType.custom,
                       allowedExtensions: ['pdf'],
                     );

                     if (pdfs != null && pdfs.paths.isNotEmpty) {
                       List<File> files = pdfs.paths.map((path) => File(path)).toList();

                       setState(() => _stream = chooseAttachments(files));
                     }

No clue which ons causes the crashes though :/

[miguelpruivo]

Does those crashes happen with apps that are using file picker 2.0.0 as well?

[Arcturus5404]

Yes! Those are with 2.0.0 file_picker

[miguelpruivo]

@Arcturus5404 which version of Flutter are you at?

[ghost]

Hello, I've been having these same reports since launch (2 months ago).
I'm now using file_picker 1.13.3, flutter 1.20.4 and the crashes continue.
I don't know if this could be related but I managed to reproduce a crash following these steps:
flutter/flutter#17950
Settings->Developer options->Don't keep activities

[miguelpruivo]

@DEMndz5 what are the steps to reproduce the issue? After picking?

[ghost]

Yes, the app crashes right after picking.

[miguelpruivo]

@DEMndz5 and you get a null pointer just like the OP?

[ghost]

Yes, this is what I'm getting on the console:
E/AndroidRuntime( 5737): FATAL EXCEPTION: Thread-6 E/AndroidRuntime( 5737): Process: io.kocho, PID: 5737 E/AndroidRuntime( 5737): java.lang.NullPointerException: Attempt to invoke virtual method 'boolean java.lang.String.equals(java.lang.Object)' on a null object reference E/AndroidRuntime( 5737): at com.mr.flutter.plugin.filepicker.FilePickerDelegate$2.run(FilePickerDelegate.java:111) E/AndroidRuntime( 5737): at java.lang.Thread.run(Thread.java:919)

[miguelpruivo]

@DEMndz5 your issue looks different (it might actually be a bug) as it relates to a different line. How are you picking the files?

PS: strangely, it references line 111 which is a blank line on latest version (only 112 has an equals() method).

[ghost]

I haven't updated to 2.0.0. I can try that later and post the results.
My issue is actually the same as OP but I was trying to reproduce the issue.

[miguelpruivo]

@DEMndz5 I suspect you are using 1.13.2.

Could you please try with 2.0.0 (you'll have to refactor a bit of code, but it's worth it) and let me know if it still happens, and if so, which line (perhaps open an issue with that)?

Thank you.

[miguelpruivo]

@Arcturus5404 I don't see nothing wrong with your code. Are you able to replicate it with a sample app?

[Arcturus5404]

@Arcturus5404 I don't see nothing wrong with your code. Are you able to replicate it with a sample app?

No I am not I'm afraid.. I tried all different kinds of emulators. I do not have these model phones, as I only use Pixels at home.

I am on the following flutter version btw:

== Use Flutter channel stable ==
> flutter --version
Flutter 1.20.4 • channel stable • https://github.com/flutter/flutter.git
Framework • revision fba99f6cf9 (3 days ago) • 2020-09-14 15:32:52 -0700
Engine • revision d1bc06f032
Tools • Dart 2.9.2

[Arcturus5404]

Maybe the issues are related from @DEMndz5, as I build my apks in release / app bundles? Maybe stuff gets confiscated when reports are being sent to the play console?

[miguelpruivo]

@Arcturus5404 any news on this?

[Arcturus5404]

No nothing.. I think its only happening with a few of my users (3 to be precise).

I will close the issue, and report back once it becomes a bigger issue!

[miguelpruivo]

@Arcturus5404 probably some of those OEM Android ROMS that might be interfering somehow with the correct activity lifecycle. It's not the first time that this happens, specially if those errors happens all on the same devices.

[Arcturus5404]

Probably yes! I will keep an eye out on the crash monitor! :) Thanks for your time! Much appreciated

[miguelpruivo]

@Arcturus5404 this should be fixed with 2.0.5. It turns out that if some devices destroyed activity while picking files, it could indeed result in a NPE. This was fixed today regarding #402.