title: Drawing a rectangle in UIView
body: <p>I am trying to draw a transparent rectangle in my UIView which has a black border. </p>
  
  <p>My code however creates a completely black rectangle. Here's my code so far:</p>
  
  <pre><code>- (void)drawRect:(CGRect)rect
  {
      // Drawing code
      CGRect rectangle = CGRectMake(0, 100, 320, 100);
      CGContextRef context = UIGraphicsGetCurrentContext();
      CGContextSetRGBFillColor(context, 0.0, 0.0, 0.0, 0.5);
      CGContextSetRGBStrokeColor(context, 0.0, 0.0, 0.0, 0.5);
      CGContextFillRect(context, rectangle);
  
  }
  </code></pre>