recently I updated my working android studio IDE into Android Studio 1.5.1. but now I\'m facing some trouble as after updating it did not generating signed apk file. but whe
I fixed this issue by completely removing Android studio and it's related files and re install it. and now its working perfectly. it may be some issue with the plugins I'm using with the IDE. So in my mac I used following terminal commands to remove android studio
rm -Rf /Applications/Android\ Studio.app
rm -Rf ~/Library/Preferences/AndroidStudio*
rm ~/Library/Preferences/com.google.android.studio.plist
rm -Rf ~/Library/Application\ Support/AndroidStudio*
rm -Rf ~/Library/Logs/AndroidStudio*
rm -Rf ~/Library/Caches/AndroidStudio*
rm -Rf ~/.gradle
rm -Rf ~/.android
then I re install the IDE and install necessary SDKs. this fixed issue for me.