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Figure 12-1. The menu and toolbar portion of the Office object model

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12.1.2 The CommandBar Object

Toolbars, menu bars, menus, submenus, and shortcut menus are all CommandBar objects. (A

shortcut menu is a menu that pops up in response to a right mouse click.) Thus, every item

pictured in Figure 12-2 is a command bar except the popup controls and the button control.

Of course, toolbars, menu bars, and shortcut menus are "top level" objects, whereas menus and

submenus emanate from toolbars, menu bars, or shortcut menus.

It is important to note that Office VBA does not treat each of these CommandBar objects in the

same way. For instance, the Count property of the CommandBars collection counts only the toplevel items: menu bars, toolbars, and shortcut menus. It does not count menus or submenus. Also,

the Add method of the CommandBars collection can be used to create toolbars or menu bars, but

not menus or submenus.

The CommandBar object has a Type property that can assume one of the constants in the

following enum:

Enum MsoBarType

msoBarTypeNormal = 0

msoBarTypeMenuBar = 1

msoBarTypePopup = 2

End Enum



' toolbar

' menu bar

' menu, submenu, or shortcut menu



12.1.3 Command-Bar Controls

The items on a toolbar, menu bar, menu, or submenu are actually controls, called command-bar

controls; that is, they are CommandBarControl objects. As we will see, there are various types of

command-bar controls, falling into two broad categories: custom command-bar controls

(including custom text boxes, drop-down list boxes, and combo boxes) and built-in command-bar

controls. Note that command-bar controls are not the same as the controls that we can place on a

UserForm; they are designed specifically for toolbars and menus.

There are two special types of custom command-bar controls that are not typical of other types of

controls. These are Popup controls and Button controls.



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12.1.3.1 Popup controls

A command-bar control of type msoControlPopup is a control whose sole purpose is to pop up

a menu (when the control is on a menu bar) or a submenu (when the control is on a menu). These

controls are naturally referred to as popup controls (see Figure 12-2). Popup controls that are

located on a menu bar take on the appearance of a recessed button when the mouse pointer is over

the control. Popup controls on a menu or submenu have a small arrow on the far right to identify

them.

Thus, the term popup is used in two different ways. A popup control is a command-bar control of

type msoControlPopup and is used to pop up a menu or submenu. A popup command bar is a

command bar of type msoBarTypePopup and is either a menu, submenu, or shortcut menu. Note

that to display a popup command bar, the user needs to activate a popup control.

12.1.3.2 Button controls

A command-bar control of type msoControlButton is called a button control. When a button

control is activated (using an accelerator key or mouse click), a macro is executed. Button controls

have a string property called OnAction, which we can set to the name of the macro that is

executed when the control is activated.



12.1.4 Adding a Menu Item

It is worth mentioning now that there are a few counterintuitive wrinkles in the process of menu

creation. In particular, we might think at first that adding a new menu should be done using the

Add method of the CommandBars collection, specifying the name of the parent menu and the

location of the new menu on the parent. After all, a menu is a CommandBar object, and this

procedure would be consistent with other cases of adding objects to a collection.

However, this is not how it is done. Instead, as we will see, a new menu (or submenu) is created

by adding a command-bar control of type msoControlPopup to the CommandBarControls

collection of the parent menu (and specifying the new control's position on the parent). Actually,

this represents a savings of effort on our behalf. For, as we have remarked, a menu or submenu

requires a popup control for activation. Thus, Microsoft makes the task of creating menus and

submenus easier by automatically creating the corresponding (empty) menu or submenu in

response to our creation of a popup control. (We will see an example of this later, so don't worry

too much if this is not perfectly clear yet.)

One word of advice before proceeding: As we will see, when creating a new toolbar or menu, you

can set one of the parameters to make the object temporary, meaning that it will be destroyed

when Excel is closed. In this way, if anything unexpected happens, it is easy to recover—just

close Excel and reopen it. Alternatively, by opening the Customize dialog box (from the Tools

menu), you can delete menu items by dragging them off of the menu, and you can delete toolbars

by using the Delete button.



12.2 The CommandBars Collection

The topmost object that relates to menus and toolbars is the CommandBars collection, which

contains all of the application's CommandBar objects. The CommandBars collection is accessible

through the CommandBars property of the Application object, that is:

Application.CommandBars



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The code in Example 12-1 will print a list of all of the CommandBar objects to the immediate

window. You may be surprised at the large number of objects, most of which are not currently

visible.

Example 12-1. Listing Excel's CommandBar Objects

Public Sub ShowCmdBars()

Dim sType as string, cbar as CommandBar

For Each cbar In Application.CommandBars

Select Case cbar.Type

Case msoBarTypeNormal

' A toolbar

sType = "Normal"

Case msoBarTypeMenuBar

' A menu bar

sType = "Menu bar"

Case msoBarTypePopup

' Menu, submenu

sType = "Popup"

End Select

Debug.Print cbar.Name & "," & sType & "," & cbar.Visible

Next

End Sub



If you execute this code, you should get the following entries, among many others:

Worksheet Menu Bar,Menu bar,True

Chart Menu Bar,Menu bar,False



This indicates that Excel's main menu bars are different for worksheets than for chartsheets, as is

evident if you look at the menus themselves. The worksheet menu bar has different controls than

the Chart menu bar. Thus, if you want to add a custom menu item to Excel's "main" menu bar,

regardless of what type of sheet is currently active, you will need to do so for both the Worksheet

Menu Bar and the Chart Menu Bar.

There is a slight complication concerning the CommandBars property that we should discuss.

When qualified with the Application object, as in Application.CommandBars, this property

returns the collection of all available built-in and custom command bars for the application which

in this case is Excel. This is why we used the fully qualified expression

Application.CommandBars in Example 12-1. Note that from a standard code module, we

can skip the qualification and just write CommandBars.

However, from a Workbook, the CommandBars property returns a different collection. In

particular, there are two possibilities. When the workbook is embedded within another application

and Excel is activated by double-clicking on that embedded workbook, the CommandBars

collection returns the collection of command bars that are available in that setting. This may be

different from the full collection of Excel command bars. If the workbook is not embedded in

another application, then the CommandBars property returns Nothing.

Note also that the Workbook object has a CommandBars property. However, this property is

meaningful only when the workbook is embedded within another application, in which case the

property returns the CommandBars collection for that application. When applied to a

nonembedded workbook, the property returns Nothing. Moreover, there is no programmatic way

to return the set of command bars attached to a workbook.



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12.3 Creating a New Menu Bar or Toolbar

As we have said, one way in which menu bars and toolbars differ from menus and submenus is in

their creation. To create a new menu bar or shortcut menu, we use the Add method of the

CommandBars collection. The syntax for the Add method is:

CommandBarsObject.Add(Name, Position, MenuBar, Temporary)



The optional Name parameter is the name of the new command bar. If this argument is omitted,

Excel VBA assigns a default name (such as "Custom 1") to the command bar. The optional

Position parameter gives the position of the new command bar. This can be set to

msoBarLeft, msoBarTop, msoBarRight, msoBarBottom , msoBarFloating (for a

floating command bar), or msoBarPopup (for a shortcut menu).

The optional Boolean MenuBar parameter is set to True for a menu bar and False for a toolbar.

The default value is False, so if the argument is omitted, a toolbar is created. Note that if you

create a new menu bar and make it visible, it will replace the existing Excel menu bar! If this

happens, you can still exit Excel by typing Alt-F4, and the normal Excel menu will reappear the

next time that you launch Excel.

Setting the optional Temporary parameter to True makes the new command bar temporary.

Temporary command bars are deleted when Excel is closed. The default value is False.

To illustrate, the following code creates a new floating toolbar called "Custom Toolbar" and

makes it visible:

Dim cbar As Office.CommandBar

Set cbar = Application.CommandBars.Add("Custom Toolbar", _

msoBarFloating, False, True)

cbar.Visible = True



It is important to note that, if a CommandBar object by the name Custom Toolbar already exists,

the previous code will produce a runtime "Invalid procedure call" error. Thus, we really should

test for the existence of the CommandBar object before using the Add method, as shown in

Example 12-2.

Example 12-2. Creating a New Toolbar

Public Sub CreateToolbar()

Dim cbar As Office.CommandBar

Dim bExists As Boolean

bExists = False

For Each cbar In Application.CommandBars

If cbar.Name = "Custom Toolbar" Then bExists = True

Next

If Not bExists Then

Set cbar = Application.CommandBars.Add("Custom Toolbar", _

msoBarFloating, False, True)

cbar.Visible = True

End If

End Sub



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