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Q142835: BUG: DBCombo Issues Click Event While Scrolling

Article: Q142835
Product(s): Microsoft Visual Basic for Windows
Version(s): 4.00 | 4.00
Operating System(s): 
Keyword(s): 
Last Modified: 11-JAN-2001

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The information in this article applies to:

- 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 
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SUMMARY
=======

While using the mouse to scroll through items in the list of a DBCombo control
the DBCombo's Click event is fired for every row scrolled.

WORKAROUND
==========

Do not rely upon the Click event of the DBCombo control to indicate when an item
has been selected. One possible workaround to detect when a user has made a
change would be to store the contents of the Text property of the DBCombo in the
DBCombo's GotFocus event, and then check to see whether this had changed in the
LostFocus event of the same control.

STATUS
======

Microsoft has confirmed this to be a issue in the Microsoft products listed at
the beginning of this article. Microsoft is researching this problem and will
post new information here in the Microsoft Knowledge Base as it becomes
available.

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

Steps to Reproduce the Problem
------------------------------

1. Start Visual Basic, or if Visual Basic is already running, start a new
  project.

2. Add a data control to Form1.

3. Change these properties of the data control:

     DatabaseName:   BIBLIO.MDB
     RecordSource:   Authors

4. Add a DBCombo control to the form.

5. Change these properties of the DBCombo control:

     RowSource:   Data1
     ListField:   AU_ID

6. Add the following code to the Click event of DBCombo1:

     Private Sub DBCombo1_Click(Area As Integer)
         Debug.Print "CLICK"
     End Sub

7. Press F5 to run the application. Use the mouse to drop the combo box. Select
  a visible number and keep the mouse button depressed. Now drag downwards to
  force the list to scroll. Notice the generated "CLICK" statements in the
  debug window.

Additional query words: 4.00 vb4win vb4all

======================================================================
Keywords          :  
Technology        : kbVBSearch kbAudDeveloper kbVB400Search kbVB400 kbVB16bitSearch
Version           : 4.00 | 4.00
Issue type        : kbbug

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