It Says "error: Failed Linking File Resources." And All The R Are Red

all of the sudden the resource file cant be accessed ,because when i try to type in setContentView(R..) it just says can't resolve the problem

Solution 1:

Just go to Build -> Clean Project, Rebuild Project or Make Project and you're good to go.

OR File -> Invalidate Caches / Restart

or check your imports at the top and look for your R if it is color gray you can delete it then try to import it again.

Solution 2:

Sometimes I get this error and Sometimes Android Studio is not compiling the new code and it's deploying the old apk. I fix this by

doing a clean on Android Project.

closing the emulator.

restarting the adb server by running adb kill-server and adb start-server from the command line.