HOWTO: Create a Basic Add-in Using VB5 or VB6

ID: Q189468

The information in this article applies to:

Microsoft Visual Basic Enterprise Edition for Windows, versions 5.0, 6.0

SUMMARY

This article describes how to create the basic framework of an Add-in for Visual Basic 5.0 or 6.0. An Add-in utilizes the Visual Basic Extensibility object model to customize and extend the Visual Basic environment.

MORE INFORMATION

Only a single step is necessary to create the code for a minimal Add-in project using Visual Basic 5.0 or 6.0, which you can by double-clicking on the Add-in Icon when starting a new Visual Basic Project.

A Visual Basic 5.0 or 6.0 Add-in can be either an ActiveX DLL or ActiveX EXE, depending upon the project type setting in the Project Properties dialog.

By default, an ActiveX EXE is created by the Add-in Wizard for Visual Basic 5.0 and an ActiveX DLL is created by default for Visual Basic 6.0. It is given the name MyAddin.vbp. In Visual Basic 5.0, three files are added to this project, connect.cls, frmAddin.frm, and Addin.bas. The contents of files are listed below with additional comments.

Visual Basic 5.0

Connect.cls


   Option Explicit

   'The IDTExtensibility is used to gain access to the
   'necessary events in the extensibility model. These four
   'interface methods must be contained in this class
   'module and must contain at least one line of code. Even
   'if the line of code is a comment.
   '
   '   + OnConnection
   '   + OnDisconnection
   '   + OnStartUpComplete
   '   + OnAddInsUpdate
   '
   '
   Implements IDTExtensibility

   'FormDisplayed keeps track of whether your form is displayed
   Public FormDisplayed As Boolean

   'VBInstance is used to identify which Visual Basic IDE the
   'Addin belongs to. Because you can have multiple
   'IDEs open, this identifies the correct IDE.
   Public VBInstance As VBIDE.VBE

   'mcbMenuCommandBar is a reference to the new menu item in the Addins
   'Menu.
   Dim mcbMenuCommandBar As Office.CommandBarControl

   'mfrmAddIn is used to reference the addins form.
   Dim mfrmAddIn As New frmAddIn

   'MenuHandler is the command bar event handler that gives
   'access to the command bar events that is used to notify the
   'addin that a menuitem was selected.
   Public WithEvents MenuHandler As CommandBarEvents

   '  Hides the Addin Form
   '
   Sub Hide()

      On Error Resume Next

      FormDisplayed = False
      mfrmAddIn.Hide

   End Sub

   '  Shows the Addin Form
   '
   Sub Show()

      On Error Resume Next

      If mfrmAddIn Is Nothing Then
         Set mfrmAddIn = New frmAddIn
      End If

      'Sets the forms Public VBInstance variable to the instance of Visual
      'Basic that the addin is being run under.

      Set mfrmAddIn.VBInstance = VBInstance

      'Sets the Forms Connect Variable to the instance of this class.

      Set mfrmAddIn.Connect = Me
      FormDisplayed = True
      mfrmAddIn.Show

   End Sub

   'This method adds the Add-In to VB.
   '
   Private Sub IDTExtensibility_OnConnection(ByVal VBInst As Object, _
      ByVal ConnectMode As vbext_ConnectMode, _
      ByVal AddInInst As VBIDE.AddIn, custom() As Variant)

      On Error GoTo error_handler

      'save the vb instance
      Set VBInstance = VBInst

      'This is a good place to set a breakpoint and
      'test various addin objects, properties and methods.
      Debug.Print VBInst.FullName

      If ConnectMode = vbext_cm_External Then
         'Used by the wizard toolbar to start this wizard.
         Me.Show
      Else
         'Create the Menu Item in the AddinMenu and
         'return a reference to it in mcbMenuCommandBar.
         '(See AddToAddInCommandBar function below.)
         '
         Set mcbMenuCommandBar = AddToAddInCommandBar("My AddIn")
         'Sets this Classes MenuHandler Event to receive events from the
         'Menu Item that was just added to the AddInCommandBar
         '(mcbMenuCommandBar).
        Set Me.MenuHandler = _
            VBInst.Events.CommandBarEvents(mcbMenuCommandBar)
      End If

      ' vbext_cm_AfterStartup indicates Addin is connected after IDE
      ' startup.
      '
      If ConnectMode = vbext_cm_AfterStartup Then
         'Checks in the Registry to see if it needs
         'to show the Addin when it connects.
         If GetSetting(App.Title, "Settings", "DisplayOnConnect", "0") = _
            "1" Then
            'Set this to display the form on connect.
            Me.Show
         End If
      End If

   Exit Sub

   error_handler:

      MsgBox Err.Description

   End Sub

   'This method removes the Add-In from VB.
   '
   Private Sub IDTExtensibility_OnDisconnection(ByVal RemoveMode As _
           vbext_DisconnectMode, custom() As Variant)

      On Error Resume Next

      'Remove the Menu Item for the Add-in
      mcbMenuCommandBar.Delete

      ' Shut down the Add-In and Save the Visible state of the
      ' addin form for the next time the addin is loaded.
      '
      If FormDisplayed Then
         SaveSetting App.Title, "Settings", "DisplayOnConnect", "1"
         FormDisplayed = False
      Else
         SaveSetting App.Title, "Settings", "DisplayOnConnect", "0"
      End If

      Unload mfrmAddIn
      Set mfrmAddIn = Nothing

   End Sub

   Private Sub IDTExtensibility_OnStartupComplete(custom() As Variant)

      If GetSetting(App.Title, "Settings", "DisplayOnConnect", "0") = _
         "1" Then
         'Set this to display the form on connect.
         Me.Show
      End If
   End Sub

   'As it has been mentioned above, all four interfaces must be
   'implemented and must contain at least one line of code for your add-in
   'to function properly. If you don't have any particular code that you
   'want to put in these procedures, just insert a comment. If the
   'procedure is empty, it will be removed by the compiler.

   Private Sub IDTExtensibility_OnAddInsUpdate(custom() As Variant)
   '
   End Sub

   'This event fires when the menu is clicked in the IDE.
   Private Sub MenuHandler_Click(ByVal CommandBarControl As Object, _
      handled As Boolean, CancelDefault As Boolean)
      Me.Show
   End Sub

   Function AddToAddInCommandBar(sCaption As String) As _
            Office.CommandBarControl
      Dim cbMenuCommandBar As Office.CommandBarControl  'command bar object
      Dim cbMenu As Object

      On Error GoTo AddToAddInCommandBarErr

      'See if the Add-Ins menu can be found.
      Set cbMenu = VBInstance.CommandBars("Add-Ins")
      If cbMenu Is Nothing Then
         'Add-Ins menu is not available so you fail.
         Exit Function
      End If

     'Create a new menu item in the Add-Ins menu.
     '
     Set cbMenuCommandBar = cbMenu.Controls.Add(1)

     'Set the menu caption.
     '
     cbMenuCommandBar.Caption = sCaption

     ' Return a Reference to the New Menu Item.
     '
     Set AddToAddInCommandBar = cbMenuCommandBar

   Exit Function

   AddToAddInCommandBarErr:

   End Function

frmAddin.frm


   Public VBInstance As VBIDE.VBE
   Public Connect As Connect

   Option Explicit

   Private Sub CancelButton_Click()
      ' Hide the Form
      '
      Connect.Hide
   End Sub

   Private Sub OKButton_Click()
      ' Place your specific Add-in code here
      '
      MsgBox "AddIn operation on: " & VBInstance.FullName
   End Sub

Addin.bas


   Option Explicit
   Declare Function WritePrivateProfileString& Lib "Kernel32" Alias
      "WritePrivateProfileStringA" (ByVal AppName$, ByVal KeyName$, _
      ByVal keydefault$, ByVal FileName$)

   '====================================================================
   'This sub should be executed from the Immediate window.
   'In order to get this app added to the VBADDIN.INI file,
   'you must change the name in the second argument to reflect
   'the correct name of your project.
   '====================================================================
   Sub AddToINI()
      Dim ErrCode As Long
      ErrCode = WritePrivateProfileString("Add-Ins32",
            "MyAddIn.Connect","0", "vbaddin.ini")
   End Sub

Visual Basic 6.0

Although the Add-in project code in Visual Basic 6.0 is very similar to the Visual Basic 5.0 code, only two files are added to the MyAddin project; the frmAddin.frm and an ActiveX Designer (connect.dsr). The ActiveX Designer is an ActiveX component that has a programmable interface and a visual interface. The Designer allows users to customize the Add-in for run-time use. The designer also contains the necessary AddinInstance Interface, rather than needing to implement the IDTExtensibility Interface.

On the General tab, the designer lets you customize some basic information for the Add-in such as the Display Name, Description, Host application and version, Initial Load Behavior, and whether the Add-in contains a User Interface.

On the Advanced tab, you have the option of selecting a Satellite DLL for Localization and a Registry key to save additional Add-in specific data.

You can add code to the add-in through code by editing the designer code and by adding code to frmAddin.

Running the Basic Add-in Using Visual Basic 5.0 or Visual Basic 6.0

If you are using Visual Basic 5.0, open the Immediate Window by pressing the CTRL+G key combination. Type "addtoini" without quotes, and press return. This step is not required in Visual Basic 6.0.

Create a new Standard EXE in a second instance of Visual Basic 5.0 or Visual Basic 6.0.

Select Add-in Manager from the Add-Ins menu.

In Visual Basic 5.0, select the check box next to MyAddin. In Visual Basic 6.0, select MyAddin.Connect, and check the "Loaded/Unloaded" check box. Click OK.

From the Add-ins menu, select "MyAddin."

Click OK to run your specific Add-in code in frmAddin.

REFERENCES

MSDN Library Visual Studio 6.0

Additional query words: kbVBp500 kbVBp600 kbVBp kbAddIn kbSetUp kbDSupport beta99 kbDSS kbVS600
kbActiveX

Keywords : kbGrpVB
Version : WINDOWS:5.0,6.0
Platform : WINDOWS
Issue type : kbhowto