AndroidStudio is alpha version for now. So you have to edit gradle build script files by yourself. Add next lines to your build.gradle
android {
signingConfigs {
release {
storeFile file('android.keystore')
storePassword "pwd"
keyAlias "alias"
keyPassword "pwd"
}
}
buildTypes {
release {
signingConfig signingConfigs.release
}
}
}
To actually run your application at emulator or device run gradle installDebug or gradle installRelease.
You can create helloworld project from AndroidStudio wizard to see what structure of gradle files is needed. Or export gradle files from working eclipse project. Also this series of articles are helpfull http://blog.stylingandroid.com/archives/1872#more-1872