title: tcl/tk widget combobox loses focus
body: <p>The tcl/tk widget iwidgets::combobox with a terrible flaw: when the list goes away, the focus goes away from the gui so you can't type in entry boxes unless you move the mouse out of the gui and back in.  </p>
  
  <p>This problem has been noted in other places, but I have not seen any solution.<br>
  a. is there a way to re-gain focus before exiting the command (-command option)?
  b. is there a better combobox widget available?  I have tried BWidgets' ComboBox but can't get that to work.... I don't want to have to build my own.</p>