BUG: Access Key for Constituent Control is Ignored

ID: Q185880

The information in this article applies to:

Microsoft Visual Basic Control Creation, Learning, Professional, and Enterprise Editions for Windows, version 5.0

SYMPTOMS

You create an ActiveX control that contains constituent controls, such as labels and command buttons, in Visual Basic. You assign these constituent controls access keys by including an ampersand (&) character within the Caption property. However, when you try to access one of the constituent controls using its access key, the control is not activated as expected.

CAUSE

The first time you access any control on the form by using an access key, any constituent controls that are disabled or hidden at that time are excluded from what you might call a "usercontrol access key map." When one of these constituent controls later becomes enabled or visible by programmatically setting its Enabled or Visible properties to True, the "map" does not get refreshed. This causes the unexpected behavior of not being able to access the control with its access key although the control is now enabled and visible.

RESOLUTION

Each time you programmatically set a constituent control's Enabled or Visible property to True, refresh its Caption property. By refreshing the constituent control's Caption property, you cause the access key mapping to include that control. See the MORE INFORMATION section for an example.

STATUS

Microsoft has confirmed this to be a bug in the Microsoft products listed at the beginning of this article. We are researching this bug and will post new information here in the Microsoft Knowledge Base as it becomes available.

MORE INFORMATION

Steps to Reproduce Behavior

Start a new ActiveX Control project in Visual Basic 5.0. UserControl1 is created by default.

Place two command buttons on UserControl1.

Set the Caption properties of the command buttons to Command&1 and Command&2.

Paste the following code into the UserControl1 code window:


      Option Explicit

      Private Sub Command1_Click()
         Command1.Visible = False
         Command2.Visible = True
      End Sub

      Private Sub Command2_Click()
         Command2.Visible = False
         Command1.Visible = True
      End Sub

Close the UserControl1 code and designer windows so that UserControl1 is available on the Toolbox.

Choose Add Project from the File menu to add a Standard EXE project. Form1 is created by default.

Using the Toolbox, place UserControl1 on Form1.

Run the project. Form1 appears.

Click Command1 using the mouse.

Press ALT+2, the access key to activate Command2.

Press ALT+1, the access key to activate Command1.

RESULT: Command1 is not activated since Command1 was hidden at the time you first accessed any control with its access key.

Workaround

Use the following code in place of the code for step 4 above:


   Option Explicit

   Private Sub Command1_Click()
      Command1.Visible = False
      Command2.Visible = True
      RefreshAccessKey Command2
   End Sub

   Private Sub Command2_Click()
      Command2.Visible = False
      Command1.Visible = True
      RefreshAccessKey Command1
   End Sub

   Private Sub RefreshAccessKey(ctl As Object)
   'Assign caption to itself to cause refresh:
      ctl.Caption = ctl.Caption
   End Sub

Additional query words: kbDSupport kbDSD kbCtrlCreate custom control ocx accelerator hot

Keywords : kbGrpVB
Version : WINDOWS:5.0
Platform : WINDOWS
Issue type : kbbug