Q130387: PRB: CLEAR EVENTS in Modal Form Does Not Clear a READ

Article: Q130387
Product(s): Microsoft FoxPro
Version(s): WINDOWS:3.0
Operating System(s): 
Keyword(s): 
Last Modified: 11-FEB-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
========

A modal form is run from a program with a DO FORM command followed by a READ
EVENTS. A command button on the form has the following method in its Click
event:

     RELEASE THISFORM
     CLEAR EVENTS

When the button is clicked, the form is released but the READ EVENTS is not
cleared.

CAUSE
=====

When a modal form is displayed, execution of a program is suspended. Modal forms
do not require a READ EVENTS. In the case described in this article, the READ
EVENTS command has not yet been executed when the CLEAR EVENTS is issued.
Program execution is suspended.

RESOLUTION
==========

Do not use the READ EVENTS command if you have a modal form or form set. To
verify the modality of your form, check the value of the WindowType property.
When a form is modal, the WindowType property is equal to 1. For more
information about displaying modal forms or form sets, search for the WINDOWTYPE
property or the SHOW method in the Visual FoxPro Help menu.

STATUS
======

This behavior is by design.

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

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

The following sample code displays a modal form. When the form is displayed and
the command button is clicked, the form is released, but control does not return
to the Command window. To correct this sample, remove the READ EVENTS and CLEAR
EVENTS commands from the code.

     omyform=CREATEOBJECT('myform')
     omyform.Show(1)       && Displays a modal form
     READ EVENTS

     DEFINE CLASS myform AS form
       WindowType=0
       ADD OBJECT mycmd AS CommandButton
       PROCEDURE mycmd.Click
         RELEASE Thisform
         CLEAR EVENTS
       ENDPROC
     ENDDEFINE

Additional query words: VFoxWin

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Keywords          :  
Technology        : kbVFPsearch kbAudDeveloper kbVFP300
Version           : WINDOWS:3.0

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