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Q176270: Treewrap.exe - Sample TreeView Control in Visual FoxPro

Article: Q176270
Product(s): Microsoft FoxPro
Version(s): WINDOWS:5.0,5.0a,6.0
Operating System(s): 
Keyword(s): kbfile kbsample kbvfp500 kbvfp600 kbDSupport
Last Modified: 10-JAN-2001

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The information in this article applies to:

- Microsoft Visual FoxPro for Windows, versions 5.0, 5.0a, 6.0 
- Microsoft Visual Basic Professional Edition for Windows, version 5.0 
- Microsoft Visual Basic Enterprise Edition for Windows, version 5.0 
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SUMMARY
=======

Visual FoxPro 5.0 or later, ships with the TreeView control that is one of the
controls in the Comctl32.ocx. When you use the TreevView control in a Visual
FoxPro application, several issues may prevent you from using all the features
of the control. However, you can work around the problems by creating an ActiveX
control in Visual Basic 5.0 that acts as a wrapper for the TreeView control.

Code that will not work if written in FoxPro may be written in Visual Basic. When
you create the control, build the functionality needed into the wrapper
control.

The sample file explains how to create the wrapper control in Visual Basic and
expose the different properties, methods, and events to a container that is
using the control. For example, the code that gives a user the ability to drag
and drop nodes in the TreeView control is built in the wrapper control. There is
also an ImageList control inside the wrapper control so that you can assign
images for the TreeView to use.

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

The following files are available for download from the Microsoft Download
Center:

  Treewrap.exe
  (http://download.microsoft.com/download/vfox60/sample9/1/W9X/EN-US/Treewrap.exe)

For additional information about how to download Microsoft Support files, click
the article number below to view the article in the Microsoft Knowledge Base:

  Q119591 How to Obtain Microsoft Support Files from Online Services

Microsoft used the most current virus detection software available on the date of
posting to scan this file for viruses. Once posted, the file is housed on secure
servers that prevent any unauthorized changes to the file.

The TreeView control example illustrates some basics of using and manipulating
the TreeView control. Because Visual FoxPro does not handle some of the methods
and properties of the TreeView control, this example uses an ActiveX control
written in Visual Basic that acts as a wrapper for the TreeView control.

The example also shows how to add Nodes to the control using the five different
relationship settings of the Nodes Collection Add Method. The sample code also
allows you to remove a selected Node or branch.

The main focus of the example is to show how to save and restore the Nodes in a
FoxPro table. The algorithm used saves the Nodes in viewing order. This allows
you to save and restore the TreeView control with the Nodes in the same order
that the user was viewing them when the application closed.

The sample file also illustrates dragging and dropping of the Nodes. The code
allows you to drag a Node and drop it on top of a different Node so that the
dragged Node is now the child of the Node on which it was dropped on. The drag
and drop code was written into the wrapper control with Visual Basic. The
wrapper control then exposes the necessary properties, methods, and events so
that you can use the control in Visual FoxPro. An Imagelist control is also
included in the wrapper control to give you the ability to assign an image to
the nodes.

NOTE: To use this sample in FoxPro, you need to issue a SYS(2333,0) before you
open or run the TreeView form. You will also need to use Regsvr32.exe and
register the Vbtofox.ocx before you use the .ocx file. (It does not matter where
the .ocx file is located for this example to work.) The syntax for using
Regsvr32.exe is as follows:

  Regsvr32 [/u] [/s] <.ocx File Name>

where:

  /u means Unregister the .ocx File /s means Silent Mode (display no messages)

If you build the .ocx file in Visual Basic, it will register the control for you.
The default in Visual Basic is to give the control a new class ID every time the
control is rebuilt. This can cause errors in Visual FoxPro because it may be
looking for a version of the control with a different class ID.

To use this sample, you will need to have Visual Basic 5.0 and Visual FoxPro 5.0
installed on your system. This sample has not been tested on a machine that did
not have both Visual Basic and Visual FoxPro installed.

Here are the steps to run the sample:

1. Use Regsver32.exe to register the .ocx file.

2. Issue a SYS(2333,0) in FoxPro.

3. Set the default directory to the location of the Treeview.scx.

4. Run the Treeview.scx form.

The files included with this sample are listed below:

- Readme.txt
- Treeview.scx FoxPro file
- Treeview.sct FoxPro file
- VBtoFox.vbp VB project file
- VBtoFox.vbw VB file
- WrapTreeView.ctl VB file
- VBtoFox.ocx
- VBtoFox.exp
- VBtoFox.lib
- Rocket.ico
- Plane.ico

REFERENCES
==========

For more information on the TreeView control see the Online Help.

Additional information on creating ActiveX controls in Visual Basic may be found
in the Visual Basic's Component Tools Guide and Books Online.

Visual FoxPro Help; 5.0, 5.0a; search on: TreeView control1

Visual Basic's Component Tools Guide and Books Online; search on: Creating
ActiveX controls in Visual Basic

(c) Microsoft Corporation 1997, All Rights Reserved. Contributions by Brian
Combs, Microsoft Corporation


Additional query words: Treewrap

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Keywords          : kbfile kbsample kbvfp500 kbvfp600 kbDSupport 
Technology        : kbVFPsearch kbVBSearch kbAudDeveloper kbPTNotAssigned kbZNotKeyword2 kbVB500Search kbVBA500 kbVB500 kbVFP500 kbVFP600 kbVFP500a
Version           : WINDOWS:5.0,5.0a,6.0
Issue type        : kbinfo

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