title: Adding subview center of screen
body: <p>I am trying to add a small icon in the center of my iPhone app screen.  Below is the code I think should work, but it isn't centering it. The position regarding the width is fine, but the height is way off, about 100 pixels off?</p>
  
  <pre><code>UIImage *pinMarker = [UIImage imageNamed:@"red_pen_marker.png"];
  UIImageView *pinMarkerView = [[UIImageView alloc] initWithImage:pinMarker];
  pinMarkerView.frame = CGRectMake(self.view.frame.size.width/2 - 9, self.view.frame.size.height/2 - 36, 18, 36);
  
  
  [self.view addSubview:pinMarkerView];
  </code></pre>
  
  <p>Any suggestions?  Maybe placing it according to the entire app window size instead of this screens view?</p>