title: wpf button location
body: <p>I am building an application.  I have a <code>Button</code> on a <code>Window</code>.  When I click the <code>Button</code>, I want 
  a new  <code>Window</code> to pop up.  But, the new <code>Window</code> must open under the <code>Button</code>.  As another way, when the <code>Window</code> pops up, the <code>Button</code> must been shown on the <code>Window</code>. How can I do that? Is that possible?</p>
  
  <p>Thanks in advance.Lilly</p>
  
  <p>My code is as follows:</p>
  
  <pre><code>private void Topics_Click(object sender, RoutedEventArgs e)
  {
       TreeView tree = new TreeView();
       tree.Top = 250;
       tree.Left = 30;
       tree.Show();
  }
  </code></pre>