Tip 117: Changing a Menu's Shortcut Key at Run Time

July 1, 1995

Abstract

When you use the Menu Editor in Microsoft® Visual Basic®, you can assign a shortcut or accelerator key to each individual menu entry. This article shows how you can change this shortcut key at run time within your Visual Basic application.

Setting Shortcut Keys in Visual Basic Menus

The Microsoft® Visual Basic® Menu Editor lets you easily design a menu system for your application. When your program is run, the user can click a menu entry to perform some kind of operation. As an alternative to using the mouse to select a menu entry, the user can type a keystroke combination such as ALT+S to invoke the menu selection. These keystroke combinations are called access or accelerator keys.

After you have designed your menu structure in the Visual Basic Menu Editor, you may decide to change the access key for a specific menu entry at run time. The example program below changes the ALT+F access key for the File menu to ALT+E.

To change a menu entry's access key at run time, you need to process the keystrokes at the form-level. That is, the KeyDown event for the underlying form will need to be monitored.

The KeyDown event in Visual Basic is triggered each time a user presses a key on the keyboard. The event is triggered for the control that has the focus. In this case, the control is the form that the menu is attached to.

The KeyDown event tells you which key or combination of keys was just pressed on the keyboard. The KeyCode argument gives you a unique number that identifies each individual key on the keyboard. For example, if the KeyCode value returned is 9, you know that the TAB key was just pressed.

In the example program below, you use the KeyDown event to determine if the user pressed the CTRL+E keystroke combination. If CTRL+E was pressed, the program displays a message box telling you that the File menu item was selected. In all other cases, the KeyDown event simply ignores the incoming keystrokes.

Example Program

This program shows how to change a menu item's shortcut key from within a Visual Basic application.

1. Create a new project in Visual Basic. Form1 is created by default.
   
   
2. Add the following code to the General Declarations section of Form1:

   Option Explicit
   Dim ShortCut As String * 1
   

3. From the Visual Basic Tools menu, click Menu Editor to create a single menu item. In the Caption field, type "&File", and in the Name field, type "mnuFile". Click OK to create the menu structure and to return to the design mode in Visual Basic.
   
   
4. Add the following code to the Form_Load event for Form1:

   Private Sub Form_Load()
       Command1.Caption = "Change ShortCut"
       KeyPreview = True
   End Sub
   

5. Add the following code to the KeyDown event for Form1:

   Private Sub Form_KeyDown(KeyCode As Integer, Shift As Integer)
       If Shift And 2 <> 2 Then Exit Sub
       If KeyCode = Asc(ShortCut) Then
           mnuFile_Click
       End If
   End Sub
   

6. Add the following code to the Click event for mnuFile:

   Private Sub mnuFile_Click()
       MsgBox "Menu was selected"
   End Sub
   

7. Add a Command Button control to Form1. Command1 is created by default. Set its Caption property to "Change Item".
   
   
8. Add the following code to the Click event for Command1:

   Private Sub Command1_Click()
       ShortCut = "E"
       mnuFile.Caption = "Fil" & "&" & LCase$(ShortCut)
   End Sub
   

Run the example program by pressing F5. Notice the menu at the top of the form. The menu entry says "File" with the letter F underlined. The letter F is the menu entry's access key. Click the command button. The menu changes to "File" with the letter e designated as the access key. Press CTRL+E on the keyboard; a message box pops up saying that that menu item was just clicked.