扩展主要活动和导航按钮。 提高可维护性。 Kotlin android 工作室

Question

I am getting close to releasing my app. Everything is working and looking fine but then I have some questions on how to improve it. I am trying to figure out some good coding practices to improve the maintainability of my app, I have a main activity with a recycler-view and I use this same recycler view, same adapter, same layout for other activities, they have some minor changes but basically whenever I have to change I am having to change all those activities and the main activity

Some key points:

-Extending the main activity

*I got an error saying its final.

*Could a fragment solve that?

*I could do everything in the main activity using recreate() but that
doesn't seen to be a good practice and messes up with navigation.

-Package name

*I had a problem with signed bundle before, I think I lost it while formating the pc and I am wondering what would be good practices to choosing package name and saving files signatures before releasing the app in the playstore.

-I am using androidx serialization for parsing json files and sqlite with live data with also some tables and a dbhandler.

*I found it very hard to change and maintain, any changes in the main object class creates a chain of changes to my app having to change the live data DB, make a migration, make changes in the dbhandler that uses that same class, and finaly a lot of trouble with kotlin serialization to parse new and old json string files.

Is there a better way that doest require as much maintenance?

Here is how I am doing my json parse

try{
   jsonparse
}catch(e:Exception){
   try{
       jsonparseWithOldClass
and so on...

I really appreciate any help or suggestions you can provide for ANY of the keypoints.