title: change UIAlertcontroller background Color
body: <p>Ok so I have this alert that I am using and I want the background of it to be black not grey like it is. I have managed to change the colour of the text for the title and the message but not the background colour. Well to the desired colour I want. I have changed it to green blue and white, but not black. When I try to change it to black it turns grey. Any suggestions will help and be appreciated. I tried this here <a href="https://stackoverflow.com/questions/26863460/how-to-change-the-background-color-of-the-uialertcontroller">How to change the background color of the UIAlertController?</a> and that is how I got to where I am now.</p>
  
  <p>Here is what I have going now:</p>
  
  <pre><code>func showAlert(title:String, message:String) {
  
      //Set up for the title color
      let attributedString = NSAttributedString(string: title, attributes: [
          NSFontAttributeName : UIFont.systemFontOfSize(15), //your font here,
          NSForegroundColorAttributeName : UIColor.whiteColor()
          ])
      //Set up for the Message Color
      let attributedString2 = NSAttributedString(string: message, attributes: [
          NSFontAttributeName : UIFont.systemFontOfSize(15), //your font here,
          NSForegroundColorAttributeName : UIColor.whiteColor()
          ])
  
      let alert = UIAlertController(title: title,message: message, preferredStyle: .Alert)
  
      alert.setValue(attributedString, forKey: "attributedTitle")
      alert.setValue(attributedString2, forKey: "attributedMessage")
      //alert.view.tintColor = UIColor.whiteColor()
      let dismissAction = UIAlertAction(title: "Dismiss", style: .Destructive, handler: nil)
          alert.addAction(dismissAction)
      self.presentViewController(alert, animated: true, completion: nil)
      //set the color of the Alert
      let subview = alert.view.subviews.first! as UIView
      let alertContentView = subview.subviews.first! as UIView
      alertContentView.backgroundColor = UIColor.blackColor()
      //alertContentView.backgroundColor = UIColor.greenColor()
      //Changes is to a grey color :( 
      /*
      alertContentView.backgroundColor = UIColor(
          red: 0,
          green: 0,
          blue: 0,
          alpha: 1.0)
      //Also another Grey Color Not batman black
      */
  
      //alertContentView.backgroundColor = UIColor.blueColor()
      //turns into a purple
  
  
  
  }
  </code></pre>