BUG: SSCommand Click Fired with Double-Click in Common Dialog

• Standard, Professional, and Enterprise Editions of Microsoft Visual Basic, 16-bit and 32-bit, for Windows, version 4.0

SYMPTOMS

Double-clicking a file name in a common dialog box that happens to be displayed immediately above an SSCommand button will cause the Click event for the SSCommand button to be fired.

WORKAROUND

This problem can be worked around in two ways. The easiest and quickest route is to replace all SSCommand buttons with regular command buttons. The regular command button does not show this behavior.

Another alternative is to set the enabled property of the SSCommand button to false immediately before showing the common dialog box. If this route is taken then a timer must be utilized to switch the enabled property of the SSCommand back to True. If Enabled is set to true immediately after the common dialog box returns (or even after a delay loop), the SSCommand will still have its click event fired. The following is a step-by-step example for this fix (this can be followed after the reproduction sample below):

1. Add a single timer control to the form.

2. Set these properties of the timer control:

      Enabled:    False
      Interval:      1
   
   

3. Add this code to the Timer1_Timer event:

      Private Sub Timer1_Timer()
         SSCommand1.Enabled = True
         Timer1.Enabled = False
      End Sub
   
   

4. In code, add this line immediately before the common dialog is shown:

   SSCommand1.Enabled = False

5. Add this line of code immediately after the common dialog is shown:

   Timer1.Enabled = True

STATUS

Microsoft has confirmed this to be an issue in the Microsoft products listed at the beginning of this article. Microsoft is researching this problem and will post new information here in the Microsoft Knowledge Base as it becomes available.

MORE INFORMATION

Steps to Reproduce

1. Start Visual Basic 4.0. Form1 is created by default.

2. Add a single SSCommand button to the form. Size the button to be very large so that the reproduction is easier to accomplish.

3. Add an additional regular command button and a single common dialog box control.

4. Add this code to Form1:

      Private Sub SSCommand1_Click()
         MsgBox "SSCommand clicked"
      End Sub
   
      Private Sub Command1_Click()
         CommonDialog1.Filter = "(*.txt)|*.txt"
         CommonDialog1.ShowOpen
      End Sub
   
   

5. Press F5 or select Start from the Run menu to run the application. Click on the regular command button to display the Open common dialog box. Ensure that the common dialog box is positioned such that a file name is immediately over the SSCommand. Double-click the file name, and see that, after the common dialog box is dismissed, a message box is displayed indicating that the SSCommand button has been clicked.