title: Changing content in UIView based on slider
body: <p>I created a Gauge using AppCode. Depending on the input, the gauge arrow in the middle rotates. I want to use a slider in Swift to determine how much the arrow in the gauge should rotate. If I hard code the input the arrow rotates to the proper position. For example, if I input 0.5, then the arrow points to the centre of the gauge. </p>
  
  <p>My problem is that my UIView never updates the arrow depending on the new slider position. The arrow is always positioned depending on the UISlider's 'Current' value. How can I get my UIView to update in real time with respect to my UISlider.</p>
  
  <p>I have a feeling that I’m supposed to put my 'drawRect' function in the 'ratingSliderChanged' action function. When I try to do this, my gauge never appears. </p>
  
  <pre><code>import Foundation
  import UIKit
  
  class RatingViewController: UIView {
  
    var sliderValue: CGFloat = 0.0
  
    @IBOutlet var newView:UIView!
  
    @IBAction func ratingSliderChanged(sender: UISlider){
     sliderValue = CGFloat(sender.value)
     println(sliderValue)
    }
  
   override func drawRect(rect: CGRect) {
  
    RatingGaugeStyleKit.drawCanvas1(frame: self.bounds, arrowAngle: sliderValue)
  
   }
  }
  </code></pre>
  
  <p>Any Suggestions? </p>