title: Hiding combobox border and drop-down just leaving text when mouse leaves
body: <p>I'm very much a noob at wpf, but I have an application to write that involves hiding certain borders / parts of controls when the mouse has left the parent container.</p>
  
  <p>I've managed to do it for textboxes and buttons just simply using storyboard animations on opacity &amp;or borderbrush colour, but a combobox is a different kettle of fish so it seems, and my guess it's not going to be easy!</p>
  
  <p>Just to reitterate, I need to hide all parts of the control that makes it look like a combobox i.e. the border and the dropdown arrow button - leaving the selected text visible.  Preferably with an animation, when the mouse leaves it's parent container.
  This xaml shows the trigger for the TextBox:</p>
  
  <pre><code>    &lt;Grid.Triggers&gt;
          &lt;EventTrigger RoutedEvent="Grid.MouseEnter"&gt;
              &lt;EventTrigger.Actions&gt;
                  &lt;BeginStoryboard Storyboard="{StaticResource showTextbox}"/&gt;
              &lt;/EventTrigger.Actions&gt;
          &lt;/EventTrigger&gt;
          &lt;EventTrigger RoutedEvent="Grid.MouseLeave"&gt;
              &lt;EventTrigger.Actions&gt;
                  &lt;BeginStoryboard Storyboard="{StaticResource hideTextbox}"/&gt;
              &lt;/EventTrigger.Actions&gt;
          &lt;/EventTrigger&gt;
      &lt;/Grid.Triggers&gt;
  </code></pre>
  
  <p>And this xaml is the storyboard for the animation.</p>
  
  <pre><code>        &lt;Storyboard x:Key="showTextbox" &gt;
              &lt;ColorAnimation Storyboard.TargetName="textBox1" Storyboard.TargetProperty="(TextBox.BorderBrush).Color" From="White" To="Black" Duration="0:0:0.25" AutoReverse="False" /&gt;
          &lt;/Storyboard&gt;
          &lt;Storyboard x:Key="hideTextbox" &gt;
              &lt;ColorAnimation Storyboard.TargetName="textBox1" Storyboard.TargetProperty="(TextBox.BorderBrush).Color" From="Black" To="White" Duration="0:0:0.25" AutoReverse="False" /&gt;
          &lt;/Storyboard&gt;
  </code></pre>
  
  <p>Thanks for any help or pointers on this!</p>