title: WPF User Control Event Firing Twice
body: <p>For some reason this event fires twice.  The other events I have on button clicks for example only fires once, but the date change on the date picker for what ever reason fires twice in a row. </p>
  
  <p>Any ideas?</p>
  
  <p>Code</p>
  
  <pre><code>public event EventHandler&lt;CalendarEventArgs&gt; DateTimeStartChanged;
  private void dateTimeStart_SelectedDateChanged(object sender, SelectionChangedEventArgs e)
  {
      if (!_loading)
      {
          e.Handled = true;
  
          if (DateTimeStartChanged != null)
              if (dateTimeStart.SelectedDate != null &amp;&amp; dateTimeEnd.SelectedDate != null)
              {
                  StartDate = (DateTime) dateTimeStart.SelectedDate;
                  DateTimeStartChanged(this,
                                          new CalendarEventArgs((DateTime) dateTimeStart.SelectedDate,
                                                                (DateTime) dateTimeEnd.SelectedDate));
              }
  
  
  
      }
  }
  </code></pre>