ACC: How to Create Pop-up Context-Sensitive Help (95/97)

ID: Q141621

The information in this article applies to:

SUMMARY

Advanced: Requires expert coding, interoperability, and multiuser skills.

One alternative to displaying your application's online Help system in a separate window is to display it in a small, shaded pop-up window within your application. To do this, you can use the Windows API WinHelp() function with its HELP_CONTEXTPOPUP argument. This article shows you how to implement such a Help system.

This article assumes that you are familiar with Visual Basic for Applications and with creating Microsoft Access applications using the programming tools provided with Microsoft Access. For more information about Visual Basic for Applications, please refer to your version of the "Building Applications with Microsoft Access" manual.

This article also assumes that you are familiar with using the Windows Help Workshop to create Windows Help files.

MORE INFORMATION

The Windows API WinHelp() function supports a large number of options. The HELP_CONTEXTPOPUP option opens a shaded pop-up window for you to display Help in. This window is similar to the window that opens when you click a glossary entry (green, underlined text) in the Microsoft Access Help system.

To implement this feature you need to do the following:

Note that jumping or branching to other Help topics from the pop-up Help window is not supported by the methods discussed in this article.

The following steps describe how to create the user-defined function to open the pop-up Help window and how to redirect the F1 key:

1. Create a module and type the following lines in the Declarations

   section:

      Declare Function WinHelp Lib "user32" Alias "WinHelpA" _
                       (ByVal hwnd As Long, _
                        ByVal lpHelpFile As String, _
                        ByVal wCommand As Long, _
                        ByVal dwData As Long) As Long
      Public Const HELP_CONTEXTPOPUP = &H8&

   NOTE: You may have some Microsoft Windows API functions defined in an
   existing Microsoft Access library; therefore, your declarations may be
   duplicates. If you receive a duplicate procedure name error message,
   remove or comment out the declarations statement in your code.

2. Type the following procedure:

      Function Help32() As Boolean
         On Local Error GoTo Help32_Err
         Dim Cid As Long, Result As Long
         On Error Resume Next
         ' Get the HelpContextID of the active control.
         ' The error is 2474 if no control is active.
         Cid = Screen.ActiveControl.HelpContextId

         If Cid = 0 Then
            ' There is no control context ID, so check the form and get
            ' the HelpContextID of the active form.
            ' The error is 2475 if no form is active.
            Cid = Screen.ActiveForm.HelpContextId
         End If

         ' If there is a context ID, open the Help file with context.
         ' Specify your custom Help file for the second argument.
         If Cid > 0 And Cid < 32767 Then
            Result = WinHelp(Application.hWndAccessApp, "C:\Myhelp.Hlp", _
            HELP_CONTEXTPOPUP, Cid)
            Help32 = True
         End If

      Help32_End:
         Exit Function

      Help32_Err:
         MsgBox Err.Description
         Resume Help32_End
      End Function

3. Create the following new macro named AutoKeys to redirect the F1 key:

      Macro Name   Condition   Action
      --------------------------------
      {F1}                     RunCode

      AutoKeys Action
      -------------------------
      RunCode
         Function Name: Help32()

REFERENCES

For more information about creating Help files, refer to the online Help supplied Windows Help Workshop and the Help Workshop's training Cards.

For more information about HelpContextID, search the Help Index for "HelpContextID" or ask the Microsoft Access 97 Office Assistant.

Additional query words:

Keywords          : kbusage 
Version           : 7.0 97
Platform          : WINDOWS
Hardware          : x86
Issue type        : kbhowto

Last Reviewed: May 20, 1999