Q136338: FIX: Windows 95 GDI Leak with Show Window Contents Setting

Article: Q136338
Product(s): Microsoft FoxPro
Version(s): 3.00
Operating System(s): 
Keyword(s): kbenvkbbuglist kbfixlist
Last Modified: 24-MAR-2000

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The information in this article applies to:

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

With the Project Manager open, GDI resources dwindle when dragging windows
within Visual FoxPro under Windows 95 if the Microsoft Plus feature "Show window
contents while dragging" is enabled.

WORKAROUND
==========

The loss of GDI resources can be prevented by disabling the Microsoft Plus "Show
window contents while dragging" feature. If the GDI resources become very low,
most may be recovered by exiting and then restarting Visual FoxPro.

STATUS
======

Microsoft has confirmed this to be a problem in the Microsoft products listed at
the beginning of this article. This problem was corrected in Visual FoxPro 3.0b
for Windows.

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

Microsoft Plus is a set of companion enhancements for Windows 95 which can be
installed to add functionality to the base feature set of Windows 95.

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

1. Install Microsoft Plus, and select the "Visual Enhancements" option when
  installing.

2. Using the right mouse button, click the Windows 95 desktop, and select
  Properties.

3. Click the Plus! tab, and select the "Show window contents while dragging"
  check box. The Plus! tab will not be available if Microsoft Plus is not
  installed.

4. Start the Windows 95 System Resource Meter from the Start Menu. Click the
  Start button. Then click Programs, click Accessories, click System Tools, and
  click Resource Meter. A green icon will appear in the Taskbar to the left of
  the clock.

  If the Resource Meter does not appear in the Start menu, it has not been
  installed. Install it by opening the Control Panel under My Computer. Click
  the Add/Remove Programs icon. Then click the Windows Setup tab, and select
  Accessories in the Components list. Click Details, and select the System
  Resource Meter check box in the Components list. Click the OK button twice.
  Windows 95 will prompt for the CD-ROM disc or floppy disk to complete the
  installation.

5. Start Visual FoxPro, and create a new project by clicking New on the File
  menu. Click Project, and then click New File. Type testproj in the Enter box
  of the Save As dialog box, and click Save.

6. Add a new form to the project by clicking the Documents tab of the Project
  Manager. Then select Forms, and click New. Click New Form to create the form.

7. Check the current System Resources by placing the mouse pointer over the
  green System Resource Meter icon in the taskbar. The percentage of available
  System, User, and GDI resources appears. Note the GDI percentage.

8. Click the Form Designer title bar in the center, hold down the mouse button
  and drag the mouse pointer around the Visual FoxPro desktop as follows: top
  right, top left, bottom left, bottom right. Repeat this about 20 times.

9. Repeat step 7, and read the GDI percentage. Observe that it falls by from 1%
  to 5% for each set of 20 drags of the form designer around the Visual FoxPro
  desktop.

Additional Notes
----------------

- The GDI does not leak memory if the Project Manager is not open or if "Show
  window contents while dragging" is not enabled.

- Closing all windows in Visual FoxPro will not fully recover the GDI resources
  lost. Closing Visual FoxPro itself will cause most or all of the GDI
  resources to be recovered.

- During a long programming session, the GDI resources will eventually become
  depleted. At this point, you need to exit Visual FoxPro and restart to
  recover the resources.

Additional query words: VFoxWin fixlist3.00b buglist3.00 sysmeter insufficient plus pack memory

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Keywords          : kbenv kbbuglist kbfixlist
Technology        : kbVFPsearch kbAudDeveloper kbVFP300
Version           : 3.00
Issue type        : kbbug
Solution Type     : kbfix

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