DOCUMENT:Q235414  11-JAN-2001  [vbwin]
TITLE   :PRB: ParentControls Property May Not Work with Some Containers
PRODUCT :Microsoft Visual Basic for Windows
PROD/VER:WINDOWS:5.0,6.0
OPER/SYS:
KEYWORDS:kbCtrlCreate kbVBp500 kbVBp600 kbGrpDSO kbDSupport

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The information in this article applies to:

 - 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
========

The ParentControls Collection of a Visual Basic UserControl is empty when the
control is placed in a non-Visual Basic Container.

CAUSE
=====

The ParentControls property is designed to return a Collection of all the
controls situated on a Form, UserDocument, or other UserControl. This property
is exposed by the Visual Basic extender object, and it is the responsibility of
the host container to implement the code needed to fill the collection. Not all
containers will support this feature. Consequently, this property might return
an empty collection in containers that do not support it.

STATUS
======

This behavior is by design.

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

Steps to Build Control
----------------------

1. Start Visual Basic and select New ActiveX Control. UserControl1 is created by
   default.

2. Change the name of the UserControl1 to MyControl and the Project name to
   MyControlServer.

3. Place a listbox and a CommandButton on the control, and in the click event of
   the CommandButton, put the following code:

       List1.Clear
       Dim x As Object
       For Each x In UserControl.ParentControls
           List1.AddItem x.Name
       Next

4. Save the project and compile to build an OCX.

Steps to Create a Visual Basic Container
----------------------------------------

1. Start Visual Basic and select New Standard EXE. Form1 is created by default.

2. Place a few controls on Form1. (The type of controls is not important.)

3. From the Project menu, select Components. From the Components list, select
   MyControlServer to add your custom control to the control toolbox.

4. Insert an instance of this control on Form1.

5. Run the project by pressing the F5 key. When you click on the CommandButton
   of MyControl1, the list box will be filled with all the names of the controls
   on Form1 (including your custom control).

Steps to Create a Visual Basic for Applications Container
---------------------------------------------------------

1. Start Microsoft Word and go to the Visual Basic Editor (ALT+F11).

2. Insert a UserForm in your project.

3. Place a few controls on the form. (The type of controls is not important.)

4. Click the right-mouse button on the Toolbox Controls and select Additional
   Controls.

5. Select MyControlServer.MyControl from the list.

6. Insert an instance of this control on the form.

7. Run the form and click on the CommandButton of your custom control. You will
   notice that the list box is not filled because the ParentControls Collection
   is empty. The Collection is empty because VBA does not implement this
   property.

(c) Microsoft Corporation 1999, All Rights Reserved.
Contributions by Harsha Bennur, Microsoft Corporation


Additional query words:

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Keywords          : kbCtrlCreate kbVBp500 kbVBp600 kbGrpDSO kbDSupport 
Technology        : kbVBSearch kbAudDeveloper kbZNotKeyword6 kbZNotKeyword2 kbVB500Search kbVB600Search kbVBA500 kbVBA600 kbVB500 kbVB600
Version           : WINDOWS:5.0,6.0
Issue type        : kbprb

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