Q149277: BUG: SSCommand Click Fired with Double-Click in Common Dialog

Article: Q149277
Product(s): Microsoft Visual Basic for Windows
Version(s): WINDOWS:4.0
Operating System(s): 
Keyword(s): kbVBp400bug
Last Modified: 11-JAN-2001

-------------------------------------------------------------------------------
The information in this article applies to:

- Microsoft Visual Basic Standard Edition, 32-bit, for Windows, version 4.0 
- Microsoft Visual Basic Professional Edition, 16-bit, for Windows, version 4.0 
- Microsoft Visual Basic Professional Edition, 32-bit, for Windows, version 4.0 
- Microsoft Visual Basic Enterprise Edition, 16-bit, for Windows, version 4.0 
- Microsoft Visual Basic Enterprise Edition, 32-bit, for Windows, version 4.0 
-------------------------------------------------------------------------------

SYMPTOMS
========

Double-clicking a file name in a common dialog box that happens to be displayed
immediately above an SSCommand button will cause the Click event for the
SSCommand button to be fired.

WORKAROUND
==========

This problem can be worked around in two ways. The easiest and quickest route is
to replace all SSCommand buttons with regular command buttons. The regular
command button does not show this behavior.

Another alternative is to set the enabled property of the SSCommand button to
false immediately before showing the common dialog box. If this route is taken
then a timer must be utilized to switch the enabled property of the SSCommand
back to True. If Enabled is set to true immediately after the common dialog box
returns (or even after a delay loop), the SSCommand will still have its click
event fired. The following is a step-by-step example for this fix (this can be
followed after the reproduction sample below):

1. Add a single timer control to the form.

2. Set these properties of the timer control:

  Enabled: False
  Interval: 1

3. Add this code to the Timer1_Timer event:

        Private Sub Timer1_Timer()
           SSCommand1.Enabled = True
           Timer1.Enabled = False
        End Sub

4. In code, add this line immediately before the common dialog is shown:

        SSCommand1.Enabled = False

5. Add this line of code immediately after the common dialog is shown:

        Timer1.Enabled = True

This code will turn off the SSCommand immediately before showing the common
dialog box. When the dialog box returns, the timer will be enabled, its event
will fire 1 millisecond later, re-enabling the SSCommand, and then it will turn
itself off.

STATUS
======

Microsoft has confirmed this to be an issue in the Microsoft products listed at
the beginning of this article.

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

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

1. Start Visual Basic 4.0. Form1 is created by default.

2. Add a single SSCommand button to the form. Size the button to be very large
  so that the reproduction is easier to accomplish.

3. Add an additional regular command button and a single common dialog box
  control.

4. Add this code to Form1:

        Private Sub SSCommand1_Click()
           MsgBox "SSCommand clicked"
        End Sub

        Private Sub Command1_Click()
           CommonDialog1.Filter = "(*.txt)|*.txt"
           CommonDialog1.ShowOpen
        End Sub

5. Press F5 or select Start from the Run menu to run the application. Click on
  the regular command button to display the Open common dialog box. Ensure that
  the common dialog box is positioned such that a file name is immediately over
  the SSCommand. Double-click the file name, and see that, after the common
  dialog box is dismissed, a message box is displayed indicating that the
  SSCommand button has been clicked.

Additional query words:

======================================================================
Keywords          : kbVBp400bug 
Technology        : kbVBSearch kbAudDeveloper kbVB400Search kbVB400 kbVB16bitSearch
Version           : WINDOWS:4.0
Issue type        : kbbug

=============================================================================

THE INFORMATION PROVIDED IN THE MICROSOFT KNOWLEDGE BASE IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND. MICROSOFT DISCLAIMS ALL WARRANTIES, EITHER EXPRESS OR IMPLIED, INCLUDING THE WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL MICROSOFT CORPORATION OR ITS SUPPLIERS BE LIABLE FOR ANY DAMAGES WHATSOEVER INCLUDING DIRECT, INDIRECT, INCIDENTAL, CONSEQUENTIAL, LOSS OF BUSINESS PROFITS OR SPECIAL DAMAGES, EVEN IF MICROSOFT CORPORATION OR ITS SUPPLIERS HAVE BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. SOME STATES DO NOT ALLOW THE EXCLUSION OR LIMITATION OF LIABILITY FOR CONSEQUENTIAL OR INCIDENTAL DAMAGES SO THE FOREGOING LIMITATION MAY NOT APPLY.

Copyright Microsoft Corporation 1986-2002.