title: How to find the ParentComboBox of a ComboBoxItem?
body: <p>How can I get the ParentComboBox of an ComboBoxItem?</p>
  
  <p>I would like to close an open ComboBox if the <I>Insert</I>-Key is pressed:</p>
  
  <pre><code> var focusedElement = Keyboard.FocusedElement;
   if (focusedElement is ComboBox)
   {
       var comboBox = focusedElement as ComboBox;
       comboBox.IsDropDownOpen = !comboBox.IsDropDownOpen;
   }
   else if (focusedElement is ComboBoxItem)
   {
       var comboBoxItem = focusedElement as ComboBoxItem;
       var parent = comboBoxItem.Parent; //this is null
       var parent = comboBoxItem.ParentComboBox; //ParentComboBox is private
       parent.IsDropDownOpen = !parent.IsDropDownOpen;
   }
  </code></pre>
  
  <p>It looks like there's no straight forward solution for this problem..</p>