title: How can I create Yosemite-style view with translucent/blurry background?
body: <p>In Yosemite sidebars have a semitransparent "vibrant" background. How can I create a view like that in 10.10/Xcode 6?</p>
  
  <p>Can I give any view such background? I've found that <code>NSOutlineView</code> will default to such background when you give it "Source list" highlight style, but the sidebar in the Calendar.app doesn't appear to be an NSOutlineView, so I wonder if there's a generic solution for this.</p>
  
  <p><img src="https://i.stack.imgur.com/zPRpW.jpg" alt="enter image description here"></p>