ADT/ODE: How to Reference Buttons on a Custom Toolbar Control (149075)

MORE INFORMATION

This article assumes that a form with a custom Toolbar control has already been created. For the examples provided in this article, the custom Toolbar control should have at least two command buttons.

The key to understanding the custom Toolbar control is understanding its object model. The custom Toolbar control is a Container object with its own properties and methods and it has a Buttons collection consisting of one or more buttons. The Button collection also has its own properties and methods. The diagram below illustrates this:

   Toolbar Control Object
     |
     +-- Properties
     |
     +-- Methods
     |
     +-- Button Collection
            |
            +-- Properties
            |
            +-- Methods
            |
            +-- Buttons
				

When you click a button on the custom Toolbar control, the toolbars ButtonClick event is triggered. It is important to note that the Toolbar control has both a Click event and a ButtonClick event. To determine which button someone clicked, the ButtonClick event must be used.

Each button in the Button collection has an "index" value and an optional key value. These values can be used to reference the desired button when selected. To view the index or key value of a particular button, using the right mouse button (right click), click the custom Toolbar control in form Design view, point to Toolbar Control Object, and then click Properties. Within the ToolbarControl Properties window, click the Buttons tab. The Buttons tab shows the Index value of a particular button and a key may also be provided.

The code examples below assumes there are at least two buttons on the custom Toolbar control. This example will display an appropriate message box, depending on which button was selected. In this example, the Button collections index property is used to determine which button was pressed. The index value stores an integer. Each button in the buttons collection will have a unique index value.

Enter the code in the Toolbar control's ButtonClick event. To enter this code, on the View menu, click Code while in the form's Design view. Then, select the Toolbar custom control object from the Object list and ButtonClick from the Proc list.

NOTE: The following code will not work within the Toolbar control's Click event when using Microsoft Access for Windows 95.

Private Sub oleToolbar_ButtonClick(ByVal Button As Object)

    Select Case Button.Index

    Case 1    ' The first button was clicked.
         Msgbox "You Selected Button #1"
    Case 2    ' The second button was clicked.
         Msgbox "You Selected Button #2"
    Case Else
         Msgbox "You Selected an invalid button"
    End Select

End Sub
				

The next example shows how to perform the same actions by referencing the Button collections "key" value instead of its Index value. The key value stores a string and this value is optional. If the key value is used, each button in the button collection should have a key and the key value must be unique.

Private Sub oleToolbar_ButtonClick(ByVal Button As Object)

     Select Case Button.Key

     Case "One"   ' The key value is "One".
          Msgbox "You Selected Button #1"

     Case "Two"   ' The key value is "two".
          Msgbox "You Selected Button #2"

     Case Else
          Msgbox "You Selected an invalid button"

     End Select

End Sub
				

NOTE: The index values for buttons in the Button collection are automatically assigned by their sequential order in the custom Toolbar control. If a button is removed, the index values are reassigned to all of the buttons in the collection. For reliable code, use the "key" value when referencing buttons. This value is user defined and cannot be changed by removing a button in the collection.