I\'ve found out that my R.java is never updated, so it doesn\'t contain information about my new resources, so I decided to delete it and thought that Eclipse would generate
One reason the R.class can go missing suddenly is when there are errors in you XML files. For instance, when you add an XML file with uppercase letters in the name like myCoolLayout.xml which is not allowed. Or when you have references that don't point to existing files, etc.