Q132534: FIX: Error Changing Grid s DynamicBackColor & DynamicForeColor

Article: Q132534
Product(s): Microsoft FoxPro
Version(s): WINDOWS:3.0,3.0b
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
========

You get the following error when changing the DynamicBackColor and
DynamicForeColor in a grid that has a class object added to a column and that
class object is the active control with the Sparse Property set to false (.F.):

  Expression evaluated to an illegal value

RESOLUTION
==========

Change either the DynamicBackColor or the DynamicForeColor but not both. Or use
the default controls that the Form Builder offers.

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 a new class named CenterChk based on Container, and store it in
  Mylib.vcx.

2. In the Class Designer, set the following properties for the container:

  Height = 19
  Width = 68
  BackStyle = 0-Transparent
  BorderWidth = 0

3. From the Form Controls toolbar, select the check box Control, and place a
  check box in the container.

4. Set the following Properties for the check box:

  BackStyle 0-Transparent
  Height = 16
  Caption = ""
  Width = 14

5. With the check box selected, click Center Horizontally and Center Vertically
  on the Format menu. Then save and close the class.

6. Open the Tastrade.dbc in the VFP\Samples\Mainsamp\Data directory.

7. Create a new form called TestGrid, and add a new property to the form called
  nCurRec.

8. Using the right mouse button, click the form to bring up the Data
  Environment. Then using the right mouse button, click the Data Environment.
  Click Add, and add the Products table.

9. From the Form Controls toolbar, select the Grid control, and add a grid to
  the form.

10. Using the right mouse button, click the grid, and choose Builder. From the
  Grid Builder, select the Products table. From the Available Fields, select
  Product_id, Product_name, and Discontinued.

11. Close the Builder by clicking OK.

12. Set the following Property for the grid:

  RowHeight = 19

13. Using the right mouse button, click the grid, then click Edit.

14. From the Form Controls toolbar, click the View Classes button and choose
  Add. Select Mylib.vcx from the Open dialog box. From the Form Controls
  Toolbar, select the CenterChk control, and add it to the Discontinued Column
  on the grid.

15. Set the following Properties for Column 3 in the grid:

  CurrentControl CenterChk1
  Width = 68
  Sparse = .F.

16. Set the following Property for Column 3 CenterChk1 Check1 in the grid:

      ControlSource = products.discontinued

17. Add the following code to the Init event of the grid:

      THISFORM.nCurRec = RECNO()
      THISFORM.Grid1.SETALL('DynamicBackColor',;
         'IIF(THISFORM.nCurRec == RECNO(), rgb(0,0,128), rgb(255,255,0))',;
         'Column')
         THISFORM.Grid1.SETALL('DynamicForeColor', ;
            'IIF(THISFORM.nCurRec == RECNO(), rgb(0,0,255), rgb(0,0,0))', ;
            'Column')
         THIS.REFRESH

18. Add the following code to the AfterRowColChange event of the grid:

      THISFORM.nCurRec = RECNO()
      THIS.REFRESH

19. Save and run the form.

For more information on creating forms, please see Chapter 9 in the Developer's
Guide. For more information on creating classes, please see Chapt1er 10 in the
Developer's Guide. And for more information on using controls on a form, please
see Chapter 11 in the Developer's Guide.

Additional query words:

======================================================================
Keywords          : kbvfp kbvfp300bBUG kbvfp500fix kbbuglist kbfixlist
Technology        : kbVFPsearch kbAudDeveloper kbVFP300 kbVFP300b
Version           : WINDOWS:3.0,3.0b
Issue type        : kbbug
Solution Type     : kbfix

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