BUG: Mouse Clicks on the Scrollbar of an Open ComboBox are Trapped by Underlying Object.

• Microsoft Visual FoxPro for Windows, versions 5.0, 5.0a, 6.0

SYMPTOMS

An object other than a list item in a combobox traps mouse clicks on the scrollbar of the drop-down list of a combobox.

STATUS

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

MORE INFORMATION

This behavior occurs under the following conditions:

1. The drop-down list of a combobox is opened by clicking on the combobox.



2. The mouse pointer is moved down the center of the drop-down list, highlighting the drop-down list items as the mouse pointer is moved.



3. The mouse is clicked more than one time, while the mouse pointer is positioned over the scroll bar of the combobox drop-down list and another control, such as a text box, command button, option group, check box, etc.

Steps to Reproduce Behavior

1. Create a program named "CBODROP.PRG" using the following code:




Public cboForm
cboForm=CreateObject("DemoForm")
cboForm.Show()

Define Class DemoForm as Form
   Caption   = "ComboBox Down Arrow Navigation"
   MinButton = .f.
   MaxButton = .f.
   Width     = 300
   height    = 200
   AutoCenter=.t.

   Add Object Combo1 as ComboBox with;
      RowSourcetype = 0, ;
      Style         = 2, ;
      Top           = 5, ;
      Left          = 5

   Add Object Command1 as CommandButton with;
      Caption = "Click Me", ;
      left    = thisform.Combo1.left+(thisform.Combo1.width/2), ;
      top     = 135, ;
      Height  = 25, ;
      Width   = 100

   Procedure init
      For i=1 to 10
         Thisform.Combo1.addlistitem(alltrim(str(i)))
      Endfor
   Endproc

   Procedure Command1.Click
      =MessageBox("Command Button Clicked.")
   Endproc

Enddefine 

2. From the Command window, type "DO CBODROP."



3. Click the combobox.



4. Drag the mouse pointer down the center of the combobox drop-down list.



5. Move the mouse pointer so that it is positioned over the combobox drop-down scrollbar and the command button.



6. Click the mouse three or more times.



7. Press the ESC key and observe that the MessageBox appears from the Command1.Click method.

© Microsoft Corporation 1999, All Rights Reserved.
Contributions by John Desch, Microsoft Corporation

Additional query words:

Keywords          : kbContainer kbCtrl kbVFp300bbug kbVFp500abug kbVFp600bug kbGrpFox kbDSupport 
Version           : WINDOWS:5.0,5.0a,6.0
Platform          : WINDOWS 
Issue type        : kbbug 

Last Reviewed: July 1, 1999