Android studio scanning files to index

I've added ember-cordova to my ember app; after that I've tried to open the project in android-studio but at startup it starts "Scanning files to index..." and never ends... While it'ìs doing that it's impossible to run the app in the emulator;

I've been googling a lot and tried many things like invalidating caches, but nothing worked; I'm using android 2.2.2; is there a knowed solution to speed it up? I guess this is not normal, the project is not that big;

I can't even understand if it's just very slow (if in N hours it will come to an end) or if it's blocked and will never end