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

Make sure you have the right settings: project structure -> Facets -> Android -> yourproject -> compiler

Check compile resources by IDE and Regenerate R.java when resources are changed.

This stole most of my morning, hopefully I'll save someone else some time:)

Answer 2

Make sure you have a gen folder in your project root. If you don't, make one yourself.

Answer 3

Use Build | Make. Actually, IDEA generates R.java file automatically every time you make a change in any XML file under the /res directory.

UPDATE: /gen directory must be present in the project and also configured as a Source root in IDEA module so that it can resolve the IDs in your source code.