Q138563: FIX: Form Not Cleared from Memory When Grid Has the Focus

Article: Q138563
Product(s): Microsoft FoxPro
Version(s): 3.00 3.00b
Operating System(s): 
Keyword(s): kbvfp kbvfp300bBUG kbvfp500fixkbbuglist kbfixlist
Last Modified: 24-MAR-2000

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The information in this article applies to:

- Microsoft Visual FoxPro for Windows, versions 3.0, 3.0b 
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SYMPTOMS
========

The RELEASE command will not release a form from memory if a grid has the focus
when the form is released. The form is cleared off the screen, but
_screen.formcount is not decremented, and _screen.activeform.name still shows
the name of the form in the Debug window. If another object on the form, such as
a text box, has the focus when the form is released, _screen.formcount is
decremented, and _screen.activeform.name is cleared.

STATUS
======

Microsoft has confirmed this to be a problem in the Microsoft products listed at
the beginning of this article. This problem has been fixed in Visual FoxPro 5.0
for Windows.

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

Steps to Reproduce Problem
--------------------------

1. Create s program named Main.prg that contains this code:

     SET PROCEDURE TO Main.prg
     ON KEY LABEL F12 CLEAR EVENTS
     ON KEY LABEL F11 SET SYSMENU TO DEFAULT

     DO MyMenu.MPR
     READ EVENTS

     SET SYSMENU TO DEFAULT

     PROCEDURE ClearForms                  && Clear all open forms
         IF _SCREEN.FormCount > 0
              FOR i = _SCREEN.FormCount TO 1 STEP -1
                   _SCREEN.Forms(i).Release
              ENDFOR
         ENDIF

2. Create a menu named MyMenu.

  a. Add a Form1 prompt that uses this command:

        DO FORM Form1.SCX

  b. Add a Clear Forms prompt that uses this command:

        DO ClearForms

  c. Add an Exit program prompt that uses this command:

        CLEAR EVENTS

  d. Generate and save the menu in the directory where Main.prg is located.

3. Create a form named Form1.

  a. Add the Customer and Orders tables located in the Vfp\Samples\Data
     directory to the data environment.

  b. Drag a field from the Customer table onto the form to create a text box.

  c. Drag the Orders table onto the form to create a grid.

  d. Save the form in the directory where Main.prg is located.

4. Open the Debug window and place _screen.formcount in the left pane.

5. Run Main.prg.

6. Click the Form1 menu, and then click the grid to give it the focus.
  _screen.formcount will equal 1. Multiple instances of Form1 can be run with
  the same result.

7. Release Form1 by clicking the Clear Forms menu. Form1 will clear off the
  screen, but _screen.formcount will still equal 1.

8. Exit the program, or click the Clear Forms menu again to return
  _screen.formcount to 0.

Additional query words:

======================================================================
Keywords          : kbvfp kbvfp300bBUG kbvfp500fix kbbuglist kbfixlist
Technology        : kbVFPsearch kbAudDeveloper kbVFP300 kbVFP300b
Version           : 3.00 3.00b
Issue type        : kbbug
Solution Type     : kbfix

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