On Thu, 22 Nov 2018 07:15:05 -0000 (UTC), arlen michael holder wrote:

I'm also going to try to downgrade the SDK from Android 8 to Android 7 for
the one YouTube app that I previously posted the source code for.

Woo hoo!

Looks like Android Studio 3.2.1 has this all figured out.
http://www.bild.me/bild.php?file=5769478androidstudio88.jpg

To change the minimum SDK version from Android 8 to 7...
o Open the project (in my case, it's the YouTube project)
o AndroidStudio321:File Project Structure app Flavors
CHANGE FROM ... Min Sdk Version: API 27: Android 8.1 (Oreo)
CHANGE TO ..... Min Sdk Version: API 24: Android 7.0 (Nougat)
o And, just in case it matters:
CHANGE FROM ... Target Sdk Version: API 27: Android 8.1 (Oreo)
CHANGE TO ..... Target Sdk Version: API 24: Android 7.0 (Nougat)

The YouTube app has compilation errors, but I can begin to debug now.