Cannot Resolve symbol R

Question

I was working on Android Studio for adding a short toast message.(I was making an Android Wear Application)

I couldn\'t know why this code has error on \'symbol R\'

Answer 1

I resolved it by editing my build.gradle file.

The compiledSdkVersion must align with your appcompat dependency.

My compileSdkVersion was 22 so I edited my appcompat dependency to

compile 'com.android.support:appcompat-v7:22.2.1'

So, I hope this can be a solution.