title: ColumnSeries from Silverlight Charting Toolkit problems
body: <p>I'm new to Silverlight development and am currently venturing into the Charting territory.
  I've been following several tutorials that show how easy it is to bind a ColumnSeries to a datasource using ItemsSource (<a href="http://silverlight.net/forums/t/44166.aspx" rel="nofollow noreferrer">http://silverlight.net/forums/t/44166.aspx</a>). </p>
  
  <p>I'm programatically adding a chart to a canvas.</p>
  
  <pre><code>Chart BudgetChart = new Chart { Title = "budget", MaxHeight= 200, MaxWidth=500};
  ColumnSeries cs = new ColumnSeries();
  BudgetChart.Series.Add(cs);
  cs.Title = "blarg";
  cs.ItemsSource = o.Budget; //returns List&lt;Budget&gt;
  cs.IndependentValueBinding = new System.Windows.Data.Binding("Budget");
  cs.DependentValueBinding = new System.Windows.Data.Binding("Year");
  </code></pre>
  
  <p>This code compiles fine. However, when I debug it, this error is throw
  However, I've been experiencing a lot of difficulty with ItemsSource. Each time I assign the ItemsSource, I get a error stating that it's Sys.InvalidOperationException: ManagedRuntimeError error #4004 in control 'Xaml1': System.NullReferenceException System.NullReferenceException: Object not set to an instance of an object. at System.Windows.Control.DataVisualization.Charting.ColumnSeries.&lt;>c__DisplayClass8.b__4()</p>
  
  <p>Please help, this error is driving me crazy!!!</p>