title: Leaving a dropped down ComboBox swallows focus in WPF
body: <p>I have the following problem: on a WPF window I placed a combo box and a button. I drop down the combo box and while the combo box is still dropped down I click on the button. The button does not react on the mouse click but the dropped down combo box closes. After a second mouse click the button reacts.
  And here's the code sample:</p>
  
  <pre><code>&lt;Window x:Class="WpfApplication1.MainWindow"
          xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
          xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" Height="100" Width="300"&gt;
      &lt;Grid&gt;
          &lt;ComboBox VerticalAlignment="Top" HorizontalAlignment="Left"
                    Width="100" IsSynchronizedWithCurrentItem="True" &gt;
              &lt;ComboBoxItem Content="item 1"/&gt;
              &lt;ComboBoxItem Content="item 2"/&gt;
              &lt;ComboBoxItem Content="item 3"/&gt;
          &lt;/ComboBox&gt;
          &lt;Button Content="Test" VerticalAlignment="Bottom" HorizontalAlignment="Right"
                  Width="100" Click="Button_Click" /&gt;
      &lt;/Grid&gt;
  &lt;/Window&gt;
  </code></pre>
  
  <p>and the code behind:</p>
  
  <pre><code>private void Button_Click(object sender, RoutedEventArgs e)
  {
      MessageBox.Show("Button clicked");
  }
  </code></pre>
  
  <p>How can I prevent the combo box to swallow the focus on the button? Thanks.</p>
  
  <p>regards mc</p>