How To Create a Basic Add-in Using VB5 or VB6
Symptoms
This article describes how to create the basic framework of an Add-in forVisual Basic 5.0 or 6.0. An Add-in utilizes the Visual Basic Extensibilityobject model to customize and extend the Visual Basic environment.
Resolution
In Visual Basic 5.0 or 6.0, you can create the code for a minimal Add-in project with a single step. You simply double-click on the Add-in icon when you start a new Visual Basic Project.
A Visual Basic 5.0 or 6.0 Add-in can be either an ActiveX DLL or ActiveXEXE, depending upon the project type setting in the Project Propertiesdialog.
By default, an ActiveX EXE is created by the Add-in Wizard for Visual Basic5.0 and an ActiveX DLL is created by default for Visual Basic 6.0. It isgiven the name MyAddin.vbp. In Visual Basic 5.0, three files are added tothis project, connect.cls, frmAddin.frm, and Addin.bas. The contents offiles 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 displayedPublic 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 NextFormDisplayed = FalsemfrmAddIn.HideEnd Sub’Shows the Addin Form’Sub Show()On Error Resume NextIf mfrmAddIn Is Nothing ThenSet mfrmAddIn = New frmAddInEnd 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 = MeFormDisplayed = TruemfrmAddIn.ShowEnd 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 instanceSet VBInstance = VBInst’This is a good place to set a breakpoint and’test various addin objects, properties and methods.Debug.Print VBInst.FullNameIf ConnectMode = vbext_cm_External Then’Used by the wizard toolbar to start this wizard.Me.ShowElse’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.ShowEnd IfEnd IfExit Suberror_handler:MsgBox Err.DescriptionEnd 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-inmcbMenuCommandBar.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 ThenSaveSetting App.Title, “Settings”, “DisplayOnConnect”, “1″FormDisplayed = FalseElseSaveSetting App.Title, “Settings”, “DisplayOnConnect”, “0″End IfUnload mfrmAddInSet mfrmAddIn = NothingEnd SubPrivate Sub IDTExtensibility_OnStartupComplete(custom() As Variant)If GetSetting(App.Title, “Settings”, “DisplayOnConnect”, “0″) = _”1″ Then’Set this to display the form on connect.Me.ShowEnd IfEnd 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.ShowEnd SubFunction AddToAddInCommandBar(sCaption As String) As _Office.CommandBarControlDim cbMenuCommandBar As Office.CommandBarControl’command bar objectDim cbMenu As ObjectOn 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 FunctionEnd 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 = cbMenuCommandBarExit FunctionAddToAddInCommandBarErr:End Function
frmAddin.frm
Public VBInstance As VBIDE.VBEPublic Connect As ConnectOption ExplicitPrivate Sub CancelButton_Click()’ Hide the Form’Connect.HideEnd SubPrivate Sub OKButton_Click()’ Place your specific Add-in code here’MsgBox “AddIn operation on: ” & VBInstance.FullNameEnd Sub
Addin.bas
Option ExplicitDeclare 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 LongErrCode = WritePrivateProfileString(“Add-Ins32″,”MyAddIn.Connect”,”0″, “vbaddin.ini”)End Sub
Visual Basic 6.0Although the Add-in project code in Visual Basic 6.0 is very similar to theVisual Basic 5.0 code, only two files are added to the MyAddin project; thefrmAddin.frm and an ActiveX Designer (connect.dsr). The ActiveX Designer isan ActiveX component that has a programmable interface and a visualinterface. The Designer allows users to customize the Add-in for run-timeuse. 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 informationfor the Add-in such as the Display Name, Description, Host application andversion, Initial Load Behavior, and whether the Add-in contains a UserInterface.
On the Advanced tab, you have the option of selecting a Satellite DLL forLocalization 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 codeand by adding code to frmAddin.
How to Run the Basic Add-in Using Visual Basic 5.0 or Visual Basic 6.0Start a new project and select the AddIn icon.If you are using Visual Basic 5.0, press CTRL+G to open the Immediate Window. Type addtoini, and press return.(NOTE: This step is not required in Visual Basic 6.0.)Press F5 to run the Add-In. This loads and registers the Add-In.Create a new Standard EXE in a second instance of Visual Basic.From the Add-Ins menu, select Add-in Manager.In Visual Basic 5.0, select the My Addin check box.
In Visual Basic 6.0, select My Add-In from the list, and select the Loaded/Unloaded check box. Click OK.From the Add-Ins menu, select My AddIn.Click OK to run your specific Add-In code in frmAddin. (A messagebox appears by default.) Click Cancel to close the form.