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Q156632: PRB: SetFocus Does Not Function in All Control Methods

Article: Q156632
Product(s): Microsoft FoxPro
Version(s): 5.0
Operating System(s): 
Keyword(s): kbvfp kbvfp500 kbvfp600
Last Modified: 17-AUG-1999

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The information in this article applies to:

- Microsoft Visual FoxPro for Windows, versions 5.0, 6.0 
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SYMPTOMS
========

In Visual FoxPro 5.0, the SetFocus method does not function in the VALID, WHEN,
RANGEHIGH, and RANGELOW methods of TextBox, EditBox, and Spinner controls.
Attempting to use the method will result in the error:

  "Cannot call SetFocus from within a When, Valid, RangeHigh or RangeLow
  event."

NOTE: The error occurs if some other control's method is called that calls a
SetFocus. That is, this error occurs if any of the events (When, Valid,
RangeHigh, RangeLow) somewhere lower in the call stack calls the SetFocus.
Example: The VALID calls a CLICK that calls a CLICK that calls a SETFOCUS; the
error still occurs.

WORKAROUND
==========

Call the SETFOCUS method in the LOSTFOCUS and GOTFOCUS methods rather than in
the VALID and WHEN methods.

STATUS
======

This behavior is by design.

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

The controls in Visual FoxPro that will cause this error are TextBox, EditBox,
and Spinner.

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

1. Create a form.

2. Add two Text boxes to the form (Text1 and Text2).

3. In the Valid event of Text1, add the following code:

     Thisform.Text2.Setfocus

4. Run the form, try to tab away from Text1, and note that the following error
  will occur:

  "Cannot call SetFocus from within a When, Valid, RangeHigh or RangeLow
  event."

Additional query words:

======================================================================
Keywords          : kbvfp kbvfp500 kbvfp600 
Technology        : kbVFPsearch kbAudDeveloper kbVFP500 kbVFP600
Version           : 5.0
Issue type        : kbprb

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