Thanks guys. You have given me a lot to work with.

1. I tried Local History and Reverting, but that did not work. Like so many other solutions the basic files were not accessible apparently.

2. Deleting the .idea directory was not going to accomplish anything since settings.gradle and build.gradle weren't in the app configuration.

3. I have searched for the build and settings gradle files but have not been able to find them. so that questions the guilt of AS. They must be somewhere, however, since the Left side app has full access to listing them and it compiles and runs fine. (Remains a mystery.)

4. I have diligently copied the app directory to backup for years now. That, apparently is sufficient for maintain code, but it is no way to try to backup the entire version. The projectFilesBackup must be created when new instances of AS are downloaded. They have the code files and all the Activity files, but none of the gradle files.

5. So the bottom line resolution must go to CommonsWare's offer. I did not set up a VCS because I did not have multiple conflicting coders. But I do have the code files and all the Activity files from the projectFilesBackup. So it looks like I will have to create a new app altogether and past the code in from that file.