oWin:Gotfocus( ) -> < xValue >

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 RETURNS:

  <xValue>     is the result of evaluation of ::bGotFocus, or nil
               if no actionblock was created


 DESCRIPTION:

  This method is called by the eventhandler of this window when he receives 
  a WM_SETFOCUS message. In turn ::GotFocus() sets the input Focus 
  to the first control of the dialog ( ::aControl[1] ), and then evaluates 
  the ::bGotFocus codeblock. 
  This will allow you to perform certain actions when the dialog gets 
  activated.