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Article: Q197027
Product(s): Microsoft FoxPro
Version(s): WINDOWS:5.0,5.0a,6.0
Operating System(s): 
Keyword(s): kbfile kbsample kbOOP kbvfp500aBUG kbvfp600bug
Last Modified: 04-NOV-1999

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The information in this article applies to:

- Microsoft Visual FoxPro for Windows, versions 5.0, 5.0a, 6.0 
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SUMMARY
=======



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

The following file is available for download from the Microsoft Software
Library:

  WTHelp.exe
  (http://support.microsoft.com/download/support/mslfiles/WTHelp.exe)

  Release Date: Dec-09-1998

  For more information about downloading files from the Microsoft Software
  Library, please see the following article in the Microsoft Knowledge Base:

  Q119591 How to Obtain Microsoft Support Files from Online Services


 File Name               Size
  ---------------------------------------------------------

  Readme.txt               10,324 bytes
  Help2.bmp                 1,318 bytes
  Whatthis.hlp             13,660 bytes
  Whatthis.hpj                631 bytes
  Whatthis.rtf             18,902 bytes
  WhatsThisHelp.vcx         2,122 bytes
  WhatsThisHelp.vct         1,910 bytes
  WhatsThis.scx             2,014 bytes
  WhatsThis.sct            10,980 bytes

NOTE: Four of these files ship with Visual FoxPro.

To work with the sample files, extract them into a directory of your choice and
set the Visual FoxPro default to the directory you choose.

Help2.bmp is one of the sample graphics files found in the
...\Graphics\Bitmaps\TlBr_W95 folder in the VFP\Samples folder with Visual
FoxPro 5.x or in the Common folder for Visual Studio or Visual FoxPro 6.0.

The three files, Whatthis.hlp, Whatthis.hpj and Whatthis.rtf, are a sample
Windows Help file, the Help project file, and the Help text source rich text
file. These files ship with Visual FoxPro and are found in the
...\Solution\Forms folder, which is found in the VFP\Samples folder with Visual
FoxPro 5.x or the Visual Studio\MSDN98\98vs\1033\Samples\VFP98 folder with
Visual Studio 6.0. These files have not been modified and are included to
provide a sample Help file with WhatsThisHelp ID numbers. The Help text in this
Help file does not match the controls on the sample form included herein. This
is just an illustration.

The remaining files listed in the previous table were created for this sample.

The WhatsThisHelp.vcx and .vct files are a visual class library that contains the
toolbar class definition that is used with the sample form.

The sample form files are WhatsThis.scx and .sct.

Working with the Sample Form
----------------------------

To see the problem and the workaround, run the WhatsThis.scx form. Follow these
steps when the form is running:

1. Click WhatsThisHelp on the form (it is the button in the top-right corner
  with the "?" on it).

2. Click on any of the objects on the form (even the form itself). Repeat this
  until you have tested all the objects.

  The form should display the following WhatsThisHelp topic for the CustomerID
  from the Help file:

  Contains a unique identifier for each customer. The ID is the first five
  letters of the Company name.

  Note that Quit displays the following:

  No Help topic is associated with this item.

  The check box displays the Help topic for the Company. The other command
  button displays the Help topic for the City.

3. Now test all the objects on the toolbar. Click WhatsThisHelp on the form, and
  click on each the toolbar button. The WhatsThisHelp topic for the form
  (Customer ID) appears. The toolbar objects display whatever WhatsThisHelp
  topic is set for the form.

4. Try the workaround by clicking the simulated WhatsThisHelp button on the
  toolbar. It has a "?" and a mouse pointer on it. Click on the Close button
  (it is the button in the top-right corner with the "x" on it). There is no
  WhatsThisHelp topic associated with this button. Next, click the simulated
  WhatsThisHelp button, and click the button with the 4 on it. Be careful not
  to let the mouse pointer move over the ToolButton with the 5 on it. Finally,
  click the simulated WhatsThisHelp button and move the mouse pointer over the
  ToolButton with the 5 on it. Notice that clicking on this button is not
  necessary for the WhatsThisHelp topic to appear. The buttons have a 4 and a 5
  on them because this is the WhatsThisHelpID assigned to them. The 5 is the
  Address Help topic, the 4 is the Title Help topic. Note that these buttons
  also have ToolTips and WAIT WINDOW commands in their click events.

5. Note that when you click the simulated WhatsThisHelp button on the toolbar,
  clicking on the form has no effect and resets the button. If you press the
  ESC key and the simulated WhatsThisHelp button simultaneously, clicking on
  the form also has no effect and resets the button. However, if you click on
  either command button or the check box, the WhatsThisHelp topic appears.
  These objects could also be set to behave in the same manner as the form when
  you use the simulated WhatsThisHelp button on the toolbar. They were made to
  function the same way under either the form's WhatsThisHelp button or the
  button on the toolbar to illustrate that it was possible. Note that the
  background of the check box does not refresh properly. This might be a
  drawback.

The Sample Code
---------------

The key code in the sample that enables you to call the proper WhatsThisHelp
topic for the toolbar buttons is in either the MouseDown or MouseMove events for
the toolbar buttons. The ToolButton with the caption of 5 has the code in the
MouseMove. The ToolButton with the caption of 4 and the buttons on the form have
the code in the MouseDown event. Placing the code in the MouseMove event is
easier to implement, but it does not have the same functionality as the real
WhatsThisHelp button. The code is as follows:

     LPARAMETERS nButton, nShift, nXCoord, nYCoord
     IF !This.Parent.Command4.Enabled AND nButton=1
        This.Parent.WhatsThisHelpID=This.WhatsThisHelpID
        This.Parent.ShowWhatsThis
        This.Parent.Command4.Enabled=.T.
     ELSE
        IF nButton=1
           This.Click
        ENDIF
     ENDIF

You do not need the ELSE portion of the IF...ENDIF block if you are using the
MouseMove event.

When the user clicks the simulated WhatsThisHelp button on the toolbar, it is
disabled. Then, when the user click the toolbar button, the MouseDown event
fires, which checks to see if the simulated WhatsThisHelp button is disabled and
if the user used the left mouse button. If so, the WhatsThisHelpID of the
toolbar is set to the WhatsThisHelpID of the toolbar button that was clicked.
Following this, the ShowWhatsThis method of the toolbar is called to display the
WhatsThisHelpID that is assigned to the toolbar. The NODEFAULT keyword has been
placed in the MouseUp event to prevent the ToolButton's click event from firing.
Therefore, when you do not want the WhatThisHelp, the MouseDown has to call the
click event. In the code above, this only happens if the user uses the left
mouse button. This is not necessary when the WhatsThisHelp is called from the
MouseMove event.

Similar code is required in the MouseDown and MouseUp events of the objects on
the form to allow them to work with the simulated WhatsThisHelp button on the
toolbar.

In addition, the WhatsThisHelp button on the form cancels if the user presses the
ESC key. This has also been implemented in the simulated WhatsThisHelp button on
the toolbar. To do this, the ESC key needs to be trapped on the form. In the
click method of the simulated WhatsThisHelp button, the form's KeyPreview
property is set to true(.T.). The following code is in the KeyPress event of the
form:

     IF !Thisformset.WhatsThisBar1.Command4.Enabled
        NODEFAULT
     ENDIF

     IF nKeyCode=27
        Thisformset.WhatsThisBar1.Command4.Enabled=.T.
        This.KeyPreview=.F.
     ENDIF

This code checks to see if the user depressed the simulated WhatsThisHelp button
on the toolbar. If so, default KeyPress actions are disabled with NODEFAULT.
Note that you cannot press the SPACEBAR to fire the Quit button's click event
and quit the form. Next, the nKeyCode is checked to see if the user pressed the
ESC key. If so, the simulated WhatsThisHelp button is re-enabled and the form's
KeyPreview property is set back to false(.F.).

The Click event of the form has been programmed to behave differently if the user
uses the simulated WhatsThisHelp button on the toolbar instead of the
WhatsThisHelp button on the form. The following code is in the MouseDown event
of the form to reset the simulated WhatsThisHelp button:

     IF !This.parent.WhatsThisBar1.Command4.Enabled
        This.parent.WhatsThisBar1.Command4.Enabled=.T.
     ENDIF

You could place this code in the MouseDown event of any of the objects on the
form so that WhatsThisHelp would not be available to the objects if the user
presses the simulated WhatsThisHelp button on the toolbar.

The WhatsThisHelpIDs for the Help file topics are in the Whatthis.hpj file. You
can open this file in Notepad or Visual FoxPro (MODIFY FILE whatthis.hpj). Look
in the [MAP] section for the ID numbers.

The following table lists all the objects in the formset and the settings for the
WhatsThisHelpID:

  Object                      WhatsThisHelpID
  ------------------------------------------------------------------------
  Form1                         1 - CustomerID
  Command1                     -1 - nothing
  Command2                      6 - City
  Check1                        2 - Company
  WhatsThisBar1                -1 - nothing
  Command1(on toolbar)          4 - Title
  Command2(on toolbar)          5 - Address
  Command3(on toolbar)         -1 - nothing
  Command4(on toolbar)         -1 - nothing, its the WhatsThisHelp button

SYMPTOMS
========

The WhatsThisHelpID property of the command buttons on a toolbar is ignored when
you use the WhatsThisHelp button on a form to get "What's This Help" for objects
on the form.

RESOLUTION
==========

To work around this, you can place a WhatsThisHelp button on the toolbar to
provide "What's This Help" for the buttons on the toolbar. WTHelp.exe contains a
sample form with a toolbar to illustrate this workaround.

WTHelp.exe is a sample that demonstrates a workaround for the WhatsThisHelpID
property of objects on a toolbar that are ignored when you use the WhatsThisHelp
button on a form.

Additional query words:

======================================================================
Keywords          : kbfile kbsample kbOOP kbvfp500aBUG kbvfp600bug 
Technology        : kbVFPsearch kbAudDeveloper kbVFP500 kbVFP600 kbVFP500a
Version           : WINDOWS:5.0,5.0a,6.0
Issue type        : kbbug
Solution Type     : kbpending

=============================================================================
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Q197027: BUG: WhatsThisHelpID on Toolbar Does Not Function as Expected
