Q238312: Fire TabStrip’s Click Event When Using Msgbox in BeforeClick

Article: Q238312
Product(s): Microsoft Visual Basic for Windows
Version(s): WINDOWS:5.0,6.0
Operating System(s): 
Keyword(s): kbActiveX kbActivexEvents kbTabCtrl kbVBp kbVBp500 kbVBp600 kbGrpDSVB kbDSupport
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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SUMMARY
=======

If a message box is displayed in a TabStrip control's BeforeClick event handler,
the TabStrip control's Click event handler will not be fired, even if the Cancel
parameter is set to False. In some situations it may be necessary to validate
the information in the BeforeClick event handler and then display a message box
to determine if the user wishes to continue. If so, the Click event should be
fired.

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

The optimum workaround depends upon the situation:

Situation 1:
------------

If you don't need to reference the TabStrip1.SelectedItem.Index property in the
Click event handler, you can call the function directly. For example:

  Private Sub TabStrip1_BeforeClick(Cancel As Integer)
     If MsgBox("Do you want to continue?", vbYesNo) = vbYes Then
        TabStrip1_Click
     Else
        Cancel = True
     End If
  End Sub

  Private Sub TabStrip1_Click()
      MsgBox "click event handler is called"
  End Sub

Situation 2:
------------

If the Click event handler is called inside the BeforeClick event, the index
value has not yet been changed. So if you must reference the
TabStrip1.SelectedItem.Index property, you must call the Click event after
exiting the BeforeClick event. One solution is to use a Timer control. For
example:

  Option Explicit

  Private Sub Form_Load()
     TabStrip1.Tabs(1).Selected = True
     Timer1.Interval = 1
     Timer1.Enabled = False
  End Sub

  Private Sub TabStrip1_BeforeClick(Cancel As Integer)
     If MsgBox("Do you want to continue?", vbYesNo) = vbYes Then
        Timer1.Enabled = True 'call the click handler
     Else
        Cancel = True
     End If
  End Sub

  Private Sub TabStrip1_Click()
     msgbox "Change to tab " & TabStrip1.SelectedItem.Index
  End Sub

  Private Sub Timer1_Timer()
     Timer1.Enabled = False
     TabStrip1_Click 'call it here
  End Sub

REFERENCES
==========

For more information regarding the TabStrip control, especially the BeforeClick
and Click events, please see the MSDN Library
(http://msdn.microsoft.com/library/default.htm).

Additional query words:

======================================================================
Keywords          : kbActiveX kbActivexEvents kbTabCtrl kbVBp kbVBp500 kbVBp600 kbGrpDSVB kbDSupport 
Technology        : kbVBSearch kbAudDeveloper kbZNotKeyword6 kbZNotKeyword2 kbVB500Search kbVB600Search kbVBA500 kbVBA600 kbVB500 kbVB600
Version           : WINDOWS:5.0,6.0
Issue type        : kbhowto

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