IntelliJ IDEA - Can't build anything, always g

Question

I'm trying to use IntelliJ IDEA to work on an Android app with a colleague that swears by it, but I'm unable to build any of the Android projects he sends me because whenever I try a build I get an error saying package R does not exist.

I have been trying out everything I can think of. Examples and other things to note are:

• Making sure I have a version of the local.properties file pointing to the root of my Android SDKs folder.

• Fiddling with various settings in the project structure dialog (I won't list them all).

• The project I'm working on has two library projects with also use the R class and they work fine.

• The intellisense within the IDE recognises the R class and comes up with the stuff I expect.

Any help would be greatly appreciated. I feel I'm missing something basic.

Answer 1

To all the hopeless people who have reached this far down the answers: I feel your pain. I have spent an hour doing nothing but trying all those things above as well as proposals from other sources. I have checked all my xml resources twice, cleaned caches, rebuilt a dozen times, even restarted the entire machine. Here is what actually worked for me:

Under 'Build Variants' (lower left corner), I selected a different Build Variant (in my case release instead of debug) for the target that had the missing R problem. Solved it.