title: TabItem ISSelected property is not working when casting from TextBlock
body: <p>Please help me, or show me direction. I have been searching net for this issue, but could not find answer for it.
  I have TextBlock and by clicking in Text Block I am adding Tab Item to my Tab Control. Everything working fine except IS Selected= true; Tab Item is not being selected. I have to select it manually. Here is my code.</p>
  
  <pre><code>var tabControl = (sender as TextBlock).FindParent&lt;TabControl&gt;();
  
  tabControl.Items.Add(new TabItem() { Header = "10 Last Documents", IsSelected = true, Content = rec, Width = 150 });
  </code></pre>
  
  <p>While casting from Button it is Ok. Please help me!</p>