What's the easiest way to force Idea to generate the R.Java file?

Question

I am trying to run Android sample applications using intellij idea and R.Java file is missing form notepad samples source directory.

Answer 1

Also make sure to check your imports. Sometimes when your IDE (eclipse & intellij as well) cannot find your generated R class and auto-imports android.R.

import android.R kills everything you are doing in your generated sources!

Cost me 30min of my life...