Q136185: PRB: _Screen.Hide or _Screen.Visible = .F. Won’t Hide Desktop

Article: Q136185
Product(s): Microsoft FoxPro
Version(s): 
Operating System(s): 
Keyword(s): 
Last Modified: 11-AUG-1999

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The information in this article applies to:

- Microsoft Visual FoxPro for Windows, version 3.0 
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SYMPTOMS
========

The Microsoft Visual FoxPro Help file states that the _Screen memory variable
has a Hide method and a Visible property. You might expect that issuing a
command such as _Screen.Hide or _Screen.Visible = .F. would cause the FoxPro
desktop to disappear, but neither has any effect on the desktop.

CAUSE
=====

This is by design. After a form or formset is hidden, Visual FoxPro activates
the last active object. If no objects were active before the formset became
active, the main Visual FoxPro window becomes active. Consequently, if you try
to hide the main FoxPro window or set its Visible property to false when there
were no prior active objects, Visual FoxPro has no place to go. As a result, the
Hide method and Visible property for _Screen are disabled.

STATUS
======

This behavior is by design.

WORKAROUND
==========

One method of hiding the FoxPro desktop is to move it off screen. For example,
create and run a program file with the following code:

Sample Code
-----------

     frmHideDesktop = CREATEOBJECT("hidedesktop")
     frmHideDesktop.SHOW(1)

      DEFINE CLASS hidedesktop AS FORM
          TOP = 17
          LEFT = 24
          DESKTOP = .T.
          CAPTION = "HideShow Example"
          MDIFORM = .T.
          oleft = .F.

          ADD OBJECT cmdHideShow AS hideshow WITH ;
              TOP = 156, ;
              LEFT = 175, ;
              HEIGHT = 29, ;
              WIDTH = 150, ;
              CAPTION = "Hide _SCREEN", ;
              NAME = "Command2"

          ADD OBJECT cmdClose AS closebutton WITH ;
              TOP = 196, ;
              LEFT = 175, ;
              HEIGHT = 29, ;
              WIDTH = 150, ;
              CAPTION = "Close", ;
              NAME = "cmdClose"

      ENDDEFINE

      DEFINE CLASS hideshow AS COMMANDBUTTON

              PROCEDURE CLICK
              IF THIS.CAPTION = "Hide _SCREEN"
                  THIS.CAPTION = "Show _SCREEN"
                  THISFORM.oleft = _SCREEN.LEFT
                  _SCREEN.LEFT = -10000
              ELSE
                  THIS.CAPTION = "Hide _SCREEN"
                  _SCREEN.LEFT = THISFORM.oleft
              ENDIF
          ENDPROC
      ENDDEFINE

      DEFINE CLASS closebutton AS COMMANDBUTTON
          PROCEDURE CLICK
              _SCREEN.LEFT = THISFORM.oleft
              THISFORM.RELEASE
          ENDPROC
      ENDDEFINE

Additional query words: VfoxWin kbvfp300

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Keywords          :  
Technology        : kbVFPsearch kbAudDeveloper kbVFP300

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