title: Change Dynamically FocusManager.FocusedElement
body: <p>I have WPF xaml code like below:</p>
  
  <pre><code>  &lt;StackPanel  FocusManager.FocusedElement="{Binding FocusedElement}"&gt;
      &lt;TextBox Name="txtbox1" Text="FirstText"/&gt;
      &lt;TextBox Name="txtbox3" Text="SecondText"/&gt;
      &lt;TextBox Name="txtbox2" Text="ThirdText"/&gt;
    &lt;/StackPanel&gt;
  </code></pre>
  
  <p>How can I Bind FocusedElement to Property in ViewModel?
   similar code below:</p>
  
  <pre><code>Switch(Type)
  {
  Case "FirstType" :
    FocusedElement = "txtbox1";
  break;
  Case "SecondType" :
     FocusedElement = "txtbox2";
  break;
  Case "ThiredType" :
     FocusedElement = "txtbox3";
  break;
  }
  </code></pre>