What I would like to do is be able to have a PDF file in a note or as a note, open the PDF through Joplin on the tablet, mark it up with the stylus, synchronize the tablet then the laptop, and see the annotations on the laptop.
So far, I have not been able to achieve this.
To be clear, when I say "mark it up with the stylus" I mean, specifically, take handwritten notes or sketch drawings directly onto the PDF. Think of the physical act of writing in a paper notebook, or an engineer redlining a drawing.
Normally how I try to this is as follows:
Open a PDF in a third party application (currently Squid for Android) and take some notes. Export from Squid to Joplin, which gets the PDF into a note. Sync the tablet, then laptop, and all is well: The PDF with those markups is now on the laptop.
What I can't do, however, is edit the PDF again. When I try (on the tablet) I'm prompted for third party software to open it with, I choose Squid, make my edits, switch back to Joplin, and... it will not sync correctly. The new markups will not appear on the Laptop.
Am I doing something obviously wrong?
Is there some way to get the behavior I want?
As of now there's no official way to save edits on mobile but you can workaround it by using Attache Plugin. Basically you setup additional sync service that will fetch any updates from mobile to desktop where updated files put instead of original one. I wrote more about this here (Section: Mobile drawing update).
I realize it's a bit finicky but once you set it up, this workaround shouldn't require any additional maintenance.
I'm still very confused by this. Since I am using DropBox as the cloud storage and sync location, I have installed Attache on Jopline/windows, mapped Dropbox to a drive letter on that machine, and set the Attache files path to that location:
C:\Users\xxxxxx\Dropbox\Apps
I have not installed the plugin on the tablet because that does not seem possible.
But this does not work. I think it boils down to me not understanding what Joplin does under the hood, or my not understanding how to force Android to save something to the right location. Possibly both.
was the original PDF file, with one hand mark-up, exported from the tablet to Joplin as its own note. It was originally just a file hanging around in the root directory of my DropBox account.
c3d8fb9ca64c4e9faf20925c6151091c.md
Is the joplin id file. At this point on the tablet (after multiple syncs), there are mulitple markups on the PDF, but only the initial one on the laptop.
I suspect I am not saving the file to the right location.
What is the right location on the tablet to save the newly marked up file to?
Just so we're clear let me repeat the process step by step
Before beginning: please make a backup of all notes
PC side
Install Attache
Point it to Dropbox folder in plugin settings; In your case you've done it with this folder C:\Users\xxxxxx\Dropbox\Apps
2.1 Please don't use the folder Apps; instead better to create some custom directory C:\Users\xxxxxx\Dropbox\Documents\Joplin-files
Make sure that Joplin is running and attache is set to replace resources on sync in its plugin settings
Android Side
Install sync app (FolderSync or Dropbox native app) and setup the same Dropbox account you setup on PC
Open PDF you want to change (0005_001.pdf) and make edits
save the edited pdf in android folder android-filesystem\Dropbox\Documents\Joplin-files
3.1 Now the folder android-filesystem\Dropbox\Documents\Joplin-files contains edited version of 0005_001.pdf
Run syncing on both Joplin mobile and Dropbox app/FolderSync.
4.1 Now the edited file 0005_001.pdf should be in Dropbox account under this path Dropbox\Documents\Joplin-files
PC side again
Run sync on Joplin Desktop and Dropbox Desktop;
1.1 Now edited pdf 0005_001.pdf should be in C:\Users\xxxxxx\Dropbox\Documents\Joplin-files`
Open edited pdf in Joplin Desktop: from the note where the pdf is attached with ctrl+click on the link
2.1 if changes weren't synced, try running sync on Joplin Desktop one more time
2.2 if changes weren't synced, try Joplin Desktop -- Menu -- Tools -- Attache -- Replace/Update resources
Hopefully this helps. If you're having trouble performing or understanding some particular step, lemme know
Perhaps I am missing something obvious, but how does this procedure make a note with a PDF in it?
It seems to rely on editing directly from the file locations, and just uses Joplin as the trigger for the synchronization.
It also doesn't entirely work as expected-- when I re-save the file, the filename changes. I am unsure if this is the OS (Android) or the application (Squid) but when I save the file, it literally lies to me and makes a new file with additional characters in it (rather than simply overwriting the original file), thus completely interfering with any synchronization attempts. Only by going manually into DropBox, removing the original file, and renaming the new file back to the original name, can I get this to work. This is cumbersome.
I am baffled by this behavior and although I find it infuriating, I suspect it is not Joplin at fault.
The procedure doesn't create notes indeed. Yes, it works around inability of Joplin to save file changes on mobile -- by saving those changes via synced directory. At the same time, it allows you "not to insert" the pdf into your note again and again every time you changed something in it on mobile.
I just installed Squid, inserted a pdf into Joplin, opened it and saved that pdf via Export feature. It changed the file name to its Joplin resource id (string of characters and numbers).
This id-name should be perfectly acceptable for the procedure (listed above) to work. In other words you don't have to change the file name to original one -- Attache plugin can handle file replacements via its id no problem.
You setup the dropbox synced folder (...Documents/Joplin-files) on Tablet
The first time you edit the pdf you open it from Joplin note (on phone) and save it in synced (dropbox) folder
on the next device (tablet in your case) you edit the pdf directly from the synced folder, and save it in the same folder after you're done with it
3.1. This step can be done multiple times with many devices (that have this synced folder) until you're happy with the PDF
Complete the procedure outlined after PC side again
I think the key here is that in order to get this to work, you have to open/edit the PDF not from Joplin itself, but from the (in this case) Dropbox folder directly. In other words, Joplin is used in a view-only fashion to look at updates performed with another application.
This is of limited utility to me at best.
If that's just the way it works, then I think I'm at the end of my journey, here.
But I did want to stop by and thank you for the generous gift of your time, trying to help me-- it is very much appreciated.
Install Attache
Point it to Dropbox folder in plugin settings; In your case you've done it with this folder 
Install sync app (FolderSync or Dropbox native app) and setup the same Dropbox account you setup on PC
