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Q272420: BUG: ComboBox Text Is Missing When DoEvents Is in GotFocus Event

Article: Q272420
Product(s): Microsoft Visual Basic for Windows
Version(s): 6.0,95,98
Operating System(s): 
Keyword(s): kbComboBox kbVBp600bug kbGrpDSVB kbDSupport
Last Modified: 13-JAN-2001

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The information in this article applies to:

- Microsoft Visual Basic Professional Edition for Windows, version 6.0, on platform(s):
   - the operating system: Microsoft Windows 2000 
   - the operating system: Microsoft Windows 95 
   - the operating system: Microsoft Windows 98 
- Microsoft Visual Basic Enterprise Edition for Windows, version 6.0, on platform(s):
   - the operating system: Microsoft Windows 2000 
   - the operating system: Microsoft Windows 95 
   - the operating system: Microsoft Windows 98 
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SYMPTOMS
========

When the Animation/Transition Display Properties system setting is turned on,
List Item text does not display in a ComboBox if a DoEvents statement is used
prior to assigning the ListIndex property in the GotFocus event.

RESOLUTION
==========

Any of the following actions can be used to work around this behavior:

- The DoEvents statement can be placed after the statement that sets the
  ListIndex.
- The Style of the ComboBox can be set to 0 - Dropdown Combo.
- The Animation/Transition setting can be cleared in the Effects tab of the
  Display Properties dialog.

STATUS
======

Microsoft has confirmed this to be a bug in the Microsoft products listed at the
beginning of this article.

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

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

1. For Windows 98 or Windows 95:

  On the Start menu, click Control Panel, select Display Properties, and then
  select the Effects tab to make sure that the Animate windows, menus and lists
  item is checked.

  For Windows 2000:

  On the Start menu, click Control Panel, select Display Properties, and then
  select the Effects tab to make sure that the Use transition effects for menus
  and tooltips item is checked.

2. Start a new Visual Basic Standard EXE project. Form1 is created by default.

3. Add two CommandButton controls and two ComboBox controls to Form1.

4. Set the Style property for both ComboBox controls to 2 - Dropdown List.

5. Add the following code to the General Declarations section of Form1:

  Private Sub Combo1_GotFocus()
     Combo1.ListIndex = 0
  End Sub

  Private Sub Combo2_GotFocus()
     DoEvents
     Combo2.ListIndex = 0
  End Sub

  Private Sub Form_Load()
     Command1.TabIndex = 0
     Combo1.TabIndex = 1
     Command2.TabIndex = 2
     Combo2.TabIndex = 3
     Combo1.AddItem "ABC"
     Combo2.AddItem "ABC"
  End Sub

6. Press the F5 key to run the program, and then click the drop-down arrow for
  ComboBox1.

7. Click on Form1, and then click the drop-down arrow for ComboBox2.

8. Click on Form1 and note that ListIndex element number zero (0) appears in
  ComboBox1. However, ListIndex element number zero (0) does not appear in
  ComboBox2. ComboBox2 remains blank.

Additional query words:

======================================================================
Keywords          : kbComboBox kbVBp600bug kbGrpDSVB kbDSupport 
Technology        : kbVBSearch kbAudDeveloper kbZNotKeyword6 kbZNotKeyword2
Version           : :6.0,95,98
Issue type        : kbbug
Solution Type     : kbnofix

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

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