DOCUMENT:Q208654  11-JAN-2001  [vbwin]
TITLE   :BUG: FontChanged Fires Twice When a Font Object Property Changed
PRODUCT :Microsoft Visual Basic for Windows
PROD/VER::6.0
OPER/SYS:
KEYWORDS:kbFont kbVBp kbVBp600bug kbGrpDSVB kbDSupport

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The information in this article applies to:

 - Microsoft Visual Basic Professional Edition for Windows, version 6.0 
 - Microsoft Visual Basic Enterprise Edition for Windows, version 6.0 
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SYMPTOMS
========

The FontChanged event sink fires more than once if the user sets a Stdfont
object to a font more than once. Setting the font object twice may be necessary
if the font object is destroyed for some reason, and then recreated. The
expected behavior is that the FontChanged event fires only once when a property
is changed.

RESOLUTION
==========

Create the font object explicitly again after destroying it, and then set up the
properties again. This makes the event fire only once.

STATUS
======

Microsoft has confirmed this to be a problem in the Microsoft products that are
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. Add a CommandButton control to Form1.

3. Add the following code to Form1's code module:

   Option Explicit
   Private WithEvents f As StdFont

   Private Sub Command1_Click()
       Me.Font.Bold = Not Me.Font.Bold
   End Sub

   Private Sub f_FontChanged(ByVal PropertyName As String)
       Print PropertyName
   End Sub

   Private Sub Form_Load()
       Set f = Me.Font
       Set f = Me.Font
   End Sub

4. Press the F5 key to run the project, and then click the CommandButton.

5. The Bold property is being changed. Note that the word Bold is printed twice
   on the form.

Step-by-Step Resolution
-----------------------

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

2. Add a CommandButton control to Form1.

3. Add the following code to the code module of Form1:

   Option Explicit
   Private WithEvents f As StdFont
   Private x As StdFont

   Private Sub Command1_Click()
      Me.Font.Bold = Not Me.Font.Bold
   End Sub

   Private Sub f_FontChanged(ByVal PropertyName As String)
       Print PropertyName
   End Sub

   Private Sub Form_Load()
      Set x = New StdFont
      x.Name = "Times New Roman"
      x.Bold = True
      x.Italic = True
      Set f = x
      Set Me.Font = f

      Set x = New StdFont
      x.Name = "Times New Roman"
      x.Bold = True
      x.Italic = False
      Set f = x
      Set Me.Font = f
   End Sub

4. Press the F5 key to run the project, click the CommandButton, and note that
   the word Bold is printed only once.

Additional query words:

======================================================================
Keywords          : kbFont kbVBp kbVBp600bug kbGrpDSVB kbDSupport 
Technology        : kbVBSearch kbAudDeveloper kbZNotKeyword6 kbZNotKeyword2 kbVB600Search kbVBA600 kbVB600
Version           : :6.0
Issue type        : kbbug
Solution Type     : kbpending

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

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