Q192196: BUG: Unable to Tab Through Controls on UserControl

Article: Q192196
Product(s): Microsoft Visual Basic for Windows
Version(s): WINDOWS:5.0,6.0
Operating System(s): 
Keyword(s): kbGrpDSVB
Last Modified: 11-JAN-2001

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The information in this article applies to:

- Microsoft Visual Basic Learning Edition for Windows, versions 5.0, 6.0 
- Microsoft Visual Basic Professional Edition for Windows, versions 5.0, 6.0 
- Microsoft Visual Basic Enterprise Edition for Windows, versions 5.0, 6.0 
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SYMPTOMS
========

When a UserControl containing constituent controls is placed on a form, while
the UserControl is the only control on the form, tabbing through the constituent
controls does not loop.

CAUSE
=====

This is because Visual Basic treats the UserControl as one control. Because
there is no other control to give focus to, no looping occurs.

RESOLUTION
==========

Manually set focus to the control with the TabIndex of 0 in the KeyPress event
of the last control in the tab sequence. See the MORE INFORMATION section below
for sample code.

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

2. From the File menu, add an ActiveX Control project. UserControl1 is created
  by default.

3. Add three CommandButton controls to UserControl1.

4. Close the UserControl1 window and add an instance of UserControl1 to Form1.

  Note: In order to reproduce this problem, UserControl1 should be the only
  control on Form1.

5. Save and run the project. Begin pressing the TAB key to tab through all the
  controls. Notice that the tab sequence does not loop through the controls on
  the UserControl.

6. Stop the project and add the following code to the KeyPress event of the last
  control in the tab sequence for the UserControl:

        Private Sub Command3_KeyPress(KeyAscii As Integer)
           Dim Ctrl As Control
           Dim FirstTab As Integer
           Dim FirstCtrl As Control
           Dim Count As Integer

           Count = 0
           ' Loop though all the controls and find
           ' the last control in the tab order
           For Each Ctrl In Controls
              If Count = 0 Then
                 FirstTab = Ctrl.TabIndex
                 Set FirstCtrl = Ctrl
              End If
              If Ctrl.TabIndex < FirstTab Then
                 FirstTab = Ctrl.TabIndex
                 Set FirstCtrl = Ctrl
              End If
              Count = Count + 1
           Next Ctrl

           ' Set focus to last control in the tab order
           If KeyAscii = 9 Then
              FirstCtrl.SetFocus
           End If
        End Sub

7. Save and run the project again. Note that the tab sequence now loops through
  all the controls on the UserControl.

Additional query words: kbDSupport kbDSD kbVBp kbVBp600bug kbVBp500bug kbCtrlCreate

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Keywords          : kbGrpDSVB 
Technology        : kbVBSearch kbAudDeveloper kbZNotKeyword6 kbZNotKeyword2 kbVB500Search kbVB600Search kbVBA500 kbVBA600 kbVB500 kbVB600
Version           : WINDOWS:5.0,6.0
Issue type        : kbbug

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