It suddenly became impossible to build my app. All of a sudden, it got stuck at building.. I tried deleting the .gradle folder, didn't help (actually made of it worse).
I uninstalled Android Studio completely, installed it again, opened a sample default project just to see if everything is ok, and I got the same problem at building. I'ts just stuck, saying :
Gradle: Resolve dependencies ':app_debugCompile'
and the loading bar is moving endlessly..