title: Intercept event when combobox edited
body: <p>I'm using a <code>ComboBox</code> as part of a larger GUI, written in python/tkinter.  </p>
  
  <p>When the drop-down selection is changed, the color is updated to indicate to the user that something has changed.</p>
  
  <p>However, the combobox also allows the user to type in their own value.  <strong>I also want the color to change when this happens.</strong></p>
  
  <p>The problem is, I don't see anything in <a href="http://www.tcl.tk/man/tcl8.5/TkCmd/ttk_combobox.htm" rel="noreferrer">the <code>ComboBox</code> documentation</a> indicating how to do this.</p>