Q124027: Changing Focus from QuickWin Using the Windows API

Article: Q124027
Product(s): Microsoft Fortran Compiler
Version(s): 5.1
Operating System(s): 
Keyword(s): 
Last Modified: 02-NOV-1999

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The information in this article applies to:

- Microsoft FORTRAN Compiler for MS-DOS, version 5.1 
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SUMMARY
=======

This article shows by example how to use Windows API calls to switch focus
between windows.

There are 2 concerns with adding functionality to a QuickWin application with the
Windows API.

- A large portion of the functionality in a Windows-based application is
  provided outside the API (by message handling, and so forth). For this
  reason, much of this functionality can't be provided under QuickWin. To get a
  full GUI interface, you'll need to use Visual C++ or Visual Basic.

- Many APIs will not behave as expected. In this example, GetFocus() works well
  at first, but if the user changes focus to a different window while the
  command setvideomode() is executing, the call to GetFocus() gets the handle
  of the wrong window. In a Windows-based application, the program would keep
  track of each window's handle as the window is created, rather than trying to
  determine the handle of a window by assuming that it currently has the focus.

MORE INFORMATION
================

The following QuickWin program creates a text window and a graphics window, sets
focus to the text window, waits for the user response, and then returns focus to
the graphics window.

This example assumes that the QuickWin Graphics Library update has been made.

To install the graphics update, follow the instructions in the README.TXT file on
the installation disk labelled "Microsoft FORTRAN, QuickWin Graphics Library"
(NOTE: The "QuickWin Graphics Library" is in fine print.)

Sample Code
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  C Compile options needed: /MW
  C Link with modified library LLIBFEW.LIB
        interface to integer*2 function getfocus
       +  [PASCAL,alias:'GetFocus']()
        end
        interface to integer*2 function setfocus
       +  [PASCAL,alias:'SetFocus'](i)
        integer*2 i
        end
        include'fgraph.fi'
        include'fgraph.fd'
        integer*2 i, texthandle, graphicshandle, getfocus, setfocus
  C     Get handle for the current window (assumed to be the text window)
        texthandle = getfocus()
  C     Create graphics window and get it's handle
        i=setvideomode($sres256color)
  C     This is NOT the same handle as returned from WGGETACTIVEQQ
        graphicshandle=getfocus()

  C     Set focus to text window
        i = setfocus(texthandle)
        write(*,*) "Hit <Enter> to continue"
        read(*,*)

  C     Set focus to graphics window
        i=setfocus(graphicshandle)
        end

Additional query words: kbinf 5.10

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Keywords          :  
Technology        : kbAudDeveloper kbFortranSearch kbZNotKeyword3 kbFORTRAN510DOS
Version           : :5.1

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