Bug when changing the file ordering criteria

[Wolfmicio]

⚠️ Before posting ⚠️

• This is a bug, not a question or an enhancement.
• I've searched for similar issues and didn't find a duplicate.
• I've written a clear and descriptive title for this issue, not just "Bug" or "Crash".
• I agree to follow Nextcloud's Code of Conduct.

Steps to reproduce

1. Click on the upload button
2. Choose any folder
3. Change the ordering criteria for the listing files (e.g A-Z -> most recent or viceversa)

Expected behaviour

The file ordering should be modified according to the chosen criteria

Actual behaviour

App crashes, modifications to sorting criteria is not applied, nor the directory within I was searching

Android version

16

Device brand and model

Google pixel 8 pro

Stock or custom OS?

Stock

Nextcloud android app version

3.34.1

Nextcloud server version

31.0.8

Using a reverse proxy?

No

Android logs

Cause of error

Exception in thread "pool-26-thread-1" java.util.ConcurrentModificationException
    at java.util.ArrayList.sort(ArrayList.java:1823)
    at java.util.Collections.sort(Collections.java:207)
    at kotlin.collections.CollectionsKt__MutableCollectionsJVMKt.sortWith(MutableCollectionsJVM.kt:42)
    at com.owncloud.android.utils.FileSortOrderByDate.sortLocalFiles(FileSortOrderByDate.kt:51)
    at com.owncloud.android.ui.adapter.LocalFileListAdapter.lambda$setSortOrder$6(LocalFileListAdapter.java:392)
    at com.owncloud.android.ui.adapter.LocalFileListAdapter.$r8$lambda$WTDJyclhOx9wYl9P9c9Mv0A876o(Unknown Source:0)
    at com.owncloud.android.ui.adapter.LocalFileListAdapter$$ExternalSyntheticLambda3.run(D8$$SyntheticClass:0)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1156)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:651)
    at java.lang.Thread.run(Thread.java:1119)

App information

• ID: com.nextcloud.client
• Version: 30340190
• Build flavor: gplay

Device information

• Brand: google
• Device: husky
• Model: Pixel 8 Pro
• Id: BP3A.251005.004.B2
• Product: husky

Firmware

• SDK: 36
• Release: 16
• Incremental: 14331693

Server error logs

Additional information

• Edit: Solved by changing the order while searching for a file

No response

[carloslcardoza]

I have the same mistake

Cause of error

Exception in thread "pool-19-thread-1" java.util.ConcurrentModificationException
    at java.util.ArrayList.sort(ArrayList.java:1823)
    at java.util.Collections.sort(Collections.java:207)
    at kotlin.collections.CollectionsKt__MutableCollectionsJVMKt.sortWith(MutableCollectionsJVM.kt:42)
    at com.owncloud.android.utils.FileSortOrderByDate.sortLocalFiles(FileSortOrderByDate.kt:51)
    at com.owncloud.android.ui.adapter.LocalFileListAdapter.lambda$setSortOrder$6(LocalFileListAdapter.java:392)
    at com.owncloud.android.ui.adapter.LocalFileListAdapter.$r8$lambda$WTDJyclhOx9wYl9P9c9Mv0A876o(Unknown Source:0)
    at com.owncloud.android.ui.adapter.LocalFileListAdapter$$ExternalSyntheticLambda3.run(D8$$SyntheticClass:0)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1156)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:651)
    at java.lang.Thread.run(Thread.java:1119)

App information

• ID: com.nextcloud.client
• Version: 30340190
• Build flavor: gplay

Device information

• Brand: samsung
• Device: dm2q
• Model: SM-S916B
• Id: AP3A.240905.015.A2
• Product: dm2qxxx

[Wolfmicio]

As far as I've seen, it goes away if, before changing the order, you type something in the search bar.
Afterwards, it works everytime... I may guess this is something related to the default directory of the new nextcloud version? (I don't know nextcloud's code, but from my programming experience, that's mostly what it seems)

If you're looking for a temporary solution, I suggest trying this out and letting me (us) know, thanks!

[carloslcardoza]

I'm still getting the same error

[jmgomer]

I'm also getting the error. It seems to me that searching isn't working and therefore the suggested workaround is not avoiding the issue in my case. Also ordering in general looks to me broken in the current nextcloud android app.

[TheShadowZone]

Adding my voice to the "please fix this" choir (see also duplicate #16196):

Cause of error

Exception in thread "pool-26-thread-1" java.util.ConcurrentModificationException
    at java.util.ArrayList.sort(ArrayList.java:1823)
    at java.util.Collections.sort(Collections.java:207)
    at kotlin.collections.CollectionsKt__MutableCollectionsJVMKt.sortWith(MutableCollectionsJVM.kt:42)
    at com.owncloud.android.utils.FileSortOrderByName.sortLocalFiles(FileSortOrderByName.kt:60)
    at com.owncloud.android.ui.adapter.LocalFileListAdapter.lambda$setSortOrder$6(LocalFileListAdapter.java:392)
    at com.owncloud.android.ui.adapter.LocalFileListAdapter.$r8$lambda$WTDJyclhOx9wYl9P9c9Mv0A876o(Unknown Source:0)
    at com.owncloud.android.ui.adapter.LocalFileListAdapter$$ExternalSyntheticLambda3.run(D8$$SyntheticClass:0)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1154)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:652)
    at java.lang.Thread.run(Thread.java:1563)

App information

• ID: com.nextcloud.client
• Version: 30340190
• Build flavor: gplay

Device information

• Brand: google
• Device: shiba
• Model: Pixel 8
• Id: BP4A.251205.006.E1
• Product: shiba

Firmware

• SDK: 36
• Release: 16
• Incremental: 14586962

[gohrner]

For documentation:

Duplicates of the sorting crash:

• Mobile app crashes when sorting on trying to upload files #16300
• crash when selecting file for upload #16250
• App crashes when sorting by newest when choosing files to upload #16192
• Crash while trying to order photos, to select which to upload #16013
• Bug when changing the file ordering criteria #15969

Well possible that I missed some...

This issue does not seem to have any priority, even though it makes the file upload feature something between really inconvenient to use to basically useless...

Incorrect file ordering when opening the file share view:

• Upload file does not show the latest file – regardless of which sorting option I choose #16190

[tarastella]

@gohrner
I went back to copying to USB sticks... a stupid, simple solution for my use case (copying photos), but it's enough.
And in a way, in my very specific case, it has been a welcome discovery as I'm trying to embrace an offline-first policy.
Coming from an open source background, I understand it takes time and effort. And for a voluntary open source project, we can't really demand too much from people giving their time for free.
But while I sympathise with the developers, it's also true that Nextcloud Android, as it is now, is pretty useless for me too.