Q157855: PRB: AfterRowColChange Event Code Does Not Enable Grid Cell

Article: Q157855
Product(s): Microsoft FoxPro
Version(s): WINDOWS:5.0
Operating System(s): 
Keyword(s): 
Last Modified: 11-DEC-1999

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The information in this article applies to:

- Microsoft Visual FoxPro for Windows, version 5.0 
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SYMPTOMS
========

If the Enabled property of a cell is changed in the AfterRowColChange event, the
effect may not take place immediately. A cell that should be enabled may be
disabled after moving to it from a disabled cell. Moving to a different cell in
that row and back again enables the cell.

CAUSE
=====

The Enabled property at the column level is checked upon entry to the field. If
it is changed after entering a field, it is not looked at again until you leave
and re-enter the field.

WORKAROUND
==========

If you wish to disallow editing of a cell based on the contents of the cell, set
the ReadOnly property to true (.T.) as shown below:

     IF numb_char.numb>80000
        This.Columns(ncolindex).ReadOnly=.F.
     ELSE
        This.Columns(ncolindex).ReadOnly=.T.
     ENDIF

Furthermore, you can change the color of the active cell by following the steps
outlined in the following article in the Microsoft Knowledge Base:

  Q129280 How to Change the Color of the Active Cell in a Grid

STATUS
======

This behavior is by design.

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

Steps to Reproduce Behavior
---------------------------

1. Create a table by entering the following command in the Command window:

  " CREATE TABLE numb_char(numb n(5),alpha c(5)) " (without the quotation
  marks)

2. Fill the numeric field with some values over 80000 and some values under.
  Fill the alpha field with anything.

3. Create a new form and place the table in the DataEnvironment.

4. Drag the table to the form to make a grid.

5. Place the following code in the AfterRowColChange event:

        IF numb_char.numb>80000
           This.Columns(ncolindex).Enabled=.t.
        ELSE
           This.Columns(ncolindex).Enabled=.f.
        ENDIF

6. Save and Run the form. Move from row to row.

Notice when you move with the arrow keys from a disabled row to one that should
be enabled, the row that should be enabled is not until you move to the left or
right and back again.

Additional query words: kbdsd VFoxWin

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Keywords          :  
Technology        : kbVFPsearch kbAudDeveloper kbVFP500
Version           : WINDOWS:5.0

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