Can't Lock PDF After Viewing on Android

Help Android App
1

Hi,

I just installed Cryptomator on my Windows PC and my android Pixel 1 phone. I’m using it to safely store PDFs originating on the PC on Dropbox so I can view them on my phone. Everything is working fine except for one problem.

When I view a pdf via Cryptomator on my phone using Foxit Viewer it views fine. However after I exit the viewer I see the message “Open writable file. Vault stays unlocked until finished editing.” The only way I’ve found to lock the file is to cancel Cryptomator.

Any idea how to fix this?

Thanks,
Mike

2

Hi and welcome :slight_smile: ,

That the notification is still visible means, that the app which you shared the file with could open it (again) to read the content or edit it locally on your device. This is possible until the notification is gone. The notification is immediately gone if you return to Cryptomator using the back button after editing/viewing. Then it will be checked if the file changed and if so, uploaded to the cloud.
The main problem is that we can not detect, if you finished the edit/view process by finishing or just suspending the other app without going back to Cryptomator using the back button.

In the 1.4.3-rc1 version, we implemented a cancel button in the notification with which you can also end the view/edit process directly from the notification bar.

TLDR;
I would recommend to open a file and after that just press the back button until you’re back in Cryptomator, than everything is fine, you can open an other file or just leave the app.

3

SailReal,

Thanks for your help. That fixes the problem.

Another way to fix this would be for Cryptomator to periodically check to see if the viewer/editor process that it launched is still running. When it’s gone then the file could be deleted and the vault made available for locking. This would have the advantage that users would not have to figure out the procedure to avoid this problem or just put up with it. It would also (I think) make deletion of the file more reliable which would increase security. If this makes sense then I’d appreciate your adding it to your list of possible enhancements.

Thanks,
Mike

1 Like
4

Thanks for your feedback!

Yes, we thought already about something like this but it isn’t quiet easy to get the running processes in Android. You have to grant usage access to this app which I would never do.

We are also not really satisfied with the current solution and will continue to think about alternatives but have not yet found a good one.

5

Hi,

OK, here’s one last idea that you probably considered that I offer just in case you didn’t. How about trying to open the decrypted file to understand what’s happening with the reader/editor? If an open for write fails then the editor or viewer has it open and is thus running. If not, then no one has it open (either they’ve opened the file, read it, and closed it, but are still displaying it, or they finished and exited) it may be OK to write it back (if it’s changed) and then delete it.

Mike

1 Like
6

Hi,

Thanks again for your feedback.
Yes we considered this solution already but the problem is, that some 3-party apps provide a possibility to toggle the mode, e.g. my file editor starts by opening the file in read mode but provides a button to switch to the write mode if you want to edit the content. Then, after editing you can save the file, switch back to read mode and now there is the problem, you can switch again to write mode…I’m afraid that’s no exception, some other apps might do the same.

We are still active in the search for solutions and will find something :slight_smile: