DOCUMENT:Q161139  24-MAR-1997  [vbwin]
TITLE   :PRB: Custom ActiveX Property Sheet Entries Are Not Saved
PRODUCT :Microsoft Visual Basic for Windows
PROD/VER:5.0
OPER/SYS:WINDOWS
KEYWORDS:kbprg vb5all vb5howto VBKBAX VBKBProgramming kbprb

======================================================================
---------------------------------------------------------------------
The information in this article applies to:

 - Microsoft Visual Basic Control Creation and Enterprise Editions,
   for Windows, version 5.0
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SYMPTOMS
========

ActiveX control property changes entered via a property page are not saved.
However, if you enter the properties via the standard property pane that
comes with Visual Basic, the changes are saved.

CAUSE
=====

The UserControl needs to explicitly inform the host development environment
of any property changes that are made via property pages or are side
effects of other property changes.

RESOLUTION
==========

To tell the host development environment of property changes, the
UserControl must invoke the PropertyChanged method of the Extender object.

STATUS
======

This behavior is by design.

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

When entering properties via the standard property pane, the host
application is setting the properties for your control and, therefore,
knows they have been changed.

The host application knows nothing about changes you make via property
pages or that there are side effects of other property changes. The user
control needs to explicitly tell the host application that properties have
been changed, so it can see the changes and save them.

The following example illustrates setting properties:

   ------ in the property page ------

      Private Sub LabelCaption_Changed()
        Changed = True     ' Enable Apply button
      End Sub

      Private Sub ApplyChanges()
      Dim X As Variant
        For Each X In SelectedControls
          X.Caption = LabelCaption.Text
        Next X
      End Sub

   ------ in the user control ------

      Public Property Let Caption(ByVal NewVal As String)
        lblMain.Caption = NewVal
        PropertyChanged "Caption"
      End Sub

This code assumes that you have all other supporting code working, such as
the InitProperties, ReadProperties, and WriteProperties events.

REFERENCES
==========

Microsoft Visual Basic Online Help, PropertyChanged Method

Microsoft Visual Basic Component Tools Guide, Chapter 9, Building ActiveX
Controls, Adding Properties to Controls, Implement Control Properties Using
Property Procedures
======================================================================
Keywords            : kbprg vb5all vb5howto VBKBAX VBKBProgramming kbprb
Technology          : kbole
Version             : 5.0
Platform            : WINDOWS
Issue type          : kbprb

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

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