R cannot be resolved to a variable. Eclipse error

Question

Good morning.

I am creating a "Android Application Project" and I get an error "R can not be resolved to a variable". The error I get nothing and create the blueprint (the "Hello World") without adding any thing more (the basic example).

Thank you.

PS: Platform SDK: API 17; Android SDK Tools: 22.0.1, Build-Android SDK Tools: 17.

Answer 1

'R' isn't generated if there are any errors in your XML files. So check all your XML files. Check for errors in naming the XML files. No capital letters etc.

If you're using Eclipse, it helps if you delete your gen folder and add it using Project > Properties > Java Build Path > Source tab > Add Source > Select gen and then Clean and Build your project

Answer 2

As stated here:

After updating to SDK Tools to rev. 22 for the first time, you may need to relaunch Android SDK Manager again and install a new item: Android SDK Build-tools.

After installing this, clean your projects and rebuild.