title: Why is "Generate Signed APK" disabled in Android Studio?
body: <p>I know there are a bunch of questions about errors that occur when Generate Signed APK is invoked in Android Studio.  However, I can't even get there!</p>
  
  <p>I'm working with Unity and <em>cough cough</em> this is my first time trying to make an Android build.  At first I thought maybe Unity would export an Eclipse build but it seems to be more up to date than that.</p>
  
  <p>Anyway, I downloaded Android Studio, and loaded the project, but the button is disabled.  I read somewhere about someone having to install gradle manually, but when I looked in the plugins folder of the app, gradle <em>is</em> there.</p>
  
  <p>I thought it might be something to do with not having connected a key store but, apparently you're supposed to do that after you select Generate Signed APK.</p>
  
  <p>Any ideas?  Thank you, I'm tearing my hair out.</p>