Hi I am completely new to Android programming and the question I am asking might be something very simple, but I do not have any idea about how to make it work, so kindly be
what worked for me:
Eventually i checked back Build Automatically.
I do not know what`s with "Build Automatically", It gives me some problem also when i export my Google play games (especially when i used external libray, like AndEngine for instance).
To fix it, i do a similar thing to fix the problem (uncheck it, clean, build manually)