can't resolve AppCompatActivity

Question

After renaming application package name, Android Studio displayed this error can\'t resolve symbol AppCompatActivity

Things I tried: <

Answer 1

Lets get going step by step: first clean project by using

Build->Clean

if this doesn't helps then use your second weapon

File>Invalidate Caches/Restart...

But the real problem begins when all the above options doesn't works so use your ultimate weapon close project and go to project location directory and delete

.idea

You can open your project now again. This worked for me and problem comes most often when you are working with VCS. And this problem is not associated with android component classes but also to the libraries, both shows the same error.