title: WPF Custom Draw Multiple Progress Bar
body: <p>In processing a group of items, I wanted to display a unified image of the status of the group, so I essentially made a Grid of a number of progressbars with transparent backgrounds and various colored foregrounds all at the same cell.</p>
  
  <p><a href="https://i.stack.imgur.com/u7RJ4.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/u7RJ4.png" alt="sample image"></a>
  </p>
  
  <p>I'm running into some transparency artifacts (purple bar is actually purple under the green, and sometimes it draws over the top, etc) and it just seems a bit wasteful.  So, I decided to make my own, but now I've got a bit of paralysis on how to do it.  Do I use the DrawingContext in FrameworkElement's OnRender, or is there something simpler?  Is there a set of general rules when it comes to making your own control?</p>
  
  <p>I pondered switching to a pie chart since those are easy to come by, but its high time I did something not off-the-shelf.</p>
  
  <p>Thanks!</p>