title: Best way to change the background color for an NSView
body: <p>I'm looking for the best way to change the <code>backgroundColor</code> of an <code>NSView</code>.  I'd also like to be able to set the appropriate <code>alpha</code> mask for the <code>NSView</code>.  Something like:</p>
  
  <pre><code>myView.backgroundColor = [NSColor colorWithCalibratedRed:0.227f 
                                                     green:0.251f 
                                                      blue:0.337 
                                                     alpha:0.8];
  </code></pre>
  
  <p>I notice that <code>NSWindow</code> has this method, and I'm not a big fan of the <code>NSColorWheel</code>, or <code>NSImage</code> background options, but if they are the best, willing to use.</p>