Xournal++ works on android

[ipesando]

Hi,
thanks to termux and temux-x11 (https://github.com/termux/termux-x11) it is possible to have a usable xournal++ on android.
It is not perfect but usable.
The main issue is the appearance of random lines.
This can be partially be tackled by choosing "Thick" as pen default and "Mouse" as input, at least for my Samsung Galaxy Tab S6.
There are still some random lines but my experience is the following.
If they disappear with an undo, you can "reset" by selecting Eraser and then the Pen again.
Sometimes even when the Eraser is selected signs and lines appear when moving the pointer, in this case one may try by using the selection tool to select and ct the affected area.

Hope it help.
Thank for the work on xournal++

[rolandlo]

Oh wow, how's that even possible?! Can you give instructions how to run Xournal++ on Android, so other users can try it out as well? Maybe we find a way to fix the random lines issue.

[ipesando]

More details (I hope I haven't forgot anything)

1. Install termux from Play Store
2. Install the app temux-x11 by downloading and installing the apk
   from https://github.com/termux/termux-x11/releases
   (see also https://github.com/termux/termux-x11 for more options)
3. open termux and get the linux shell then
   pkg install x11-repo
   pkg install xfce4
   pkg install xournalpp
   pkg install termux-x11-nightly
   (it requires some space...)
4. start the app termux-x11
5. switch to termux again and from the shell
   termux-x11 :1 -xstartup "dbus-launch --exit-with-session xfce4-session"
6. switch to termux-x11 and you see the xfce4 window manager
   a) start the x-terminal
   b) use the android "back" to get the keyboard
   c) launch xournalpp from the shell of the x-terminal
   d) customize xournalpp: default size->thick, input->mouse

I tried also with changing the pressure sensitivity for avoiding artifacts but without luck.

[rolandlo]

I got it to install on my Android phone (Galaxy Samsung S8) as well. One more step (before step 5) was needed for me before termux-x11 got connection:

apt update && apt upgrade

I'm amazed that it runs. However running it on a phone (which is pretty small) is not a great user experience. I don't even have a stylus to draw. On an Android tablet it may be much more enyojable.