My ADT worked correctly as same as whatever saw in tutorial until 2days ago when i created a project like before and also i selected \"create a blank activity\" and i expect
As one guy said
I had the same problem even though I downloaded the Android SDK and did a clean install, but I just resolved it. I tried to click "Help" -> "Check for updates", and then I got a pop-up message saying everything was up to date, but after further research it appeared to me it wasn't up to date. What you need to do is click "Help" -> "Install new software" and install (this will update it) from this url: https://dl-ssl.google.com/android/eclipse/
See here thread https://code.google.com/p/android/issues/detail?id=66647