I recently modified my Galaxy A8 with android pie and wanted to include Viper4Android, but there appeared to be no support for it at first. This turned out to not be true, and I could not find any comprehensive guide that told me how to do it for android pie, but it turns out there is a way!
I am not at all a root-expert and I do not understand the specifics of rooting. I am not responsible for any negative consequences to your phone. I also have some little anomalies on my phone as a few com.sec.xxxxx files are not found by the Titanium Backup app, whilst it appears according to the internet there should be. Therefore, I recommend you only do this if you can reinstall your stock firmware easily until more people have given conformation that my guide here works.
- Custom Recovery like TWRP
- Root with Magisk (other root apps like SU don't appear to work, as the specific module which this guide relies on is Magisk-only
- Viper4Android APK found here (this guide is for Oreo, however it worked for me with my work-around)
- SELink set to permissive.
(I had to download a custom kernel to do this, as terminal commands, SELink changer or Knox deletion did not work to change SELink for me. I used Quantum Kernel (found here on XDA in development thread section), which works with the february 2020 security update. Great custom kernel btw!)
So you install the Viper4Android APK. This app will not work properly because it's meant for Oreo of course, so then you install the Viper4Android FX module found in Magisk, then you open the app you just installed and follow the prompts. The app GUI should change and look more modernized than before. Say yes to the driver installation and give the app SuperSU rights.
You should be good to go from here. Please do tell if my guide works for you.
All credits go to the amazing developers of the respective softwares. I only wrote this guide to make the road for the next guy like me easier. Have fun with Viper!