“R cannot be resolved to a variable”? in Android

Dont worry. First you may clean the project, then run the project. If this does not work then follow the following links:

• Here is the best way to solve this problem: Android Development- Where is my R.Java file?
• R cannot be resolved - Android error
• R cannot be resolved to a variable
• R cannot be resolved to a variable -- mailing list entry
• Fixed: R cannot be resolved to a variable

Sources: http://stackoverflow.com/questions/7824730/r-cannot-be-resolved-to-a-variable/7824975#7824975