Can I get some help finding a native component while trying to modify my Andriod incoming and outgoing call screens?

[AC Question]

andriod incoming outgoing call screens

I am working on modifying the Incoming/Outgoing call screens, for some special numbers. For this, planning to modify the native code and perform aosp full build.

Need help on finding out the native component, which needs to be modified for this requirement.

Thanks, pruthvi.