BUG: Progress Bar Does Not Paint When DragMode Automatic

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

SYMPTOMS

If the DragMode property of the Microsoft Windows 95 Progress Bar control is set to 1-Automatic, it does not paint if the progress of the control is updated.

STATUS

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

WORKAROUND

Set DragMode to 0-Manual before progress is updated, and then reset it to 1- Automatic after the control has had time to paint.

Instead of updating the value directly, the following subroutine can be called to update the value. The first parameter is the control itself and the second parameter is the new value for the progress:

   Public Sub UpdateProgress(ProgBar As Object, NewValue As Integer)
      'Turn drag to Manual briefly.
      ProgBar. Value = 0
      'Update the progress.
      ProgBar.Value = NewValue
      'Turn drag to Automatic, and allow time for repaint.
      ProgBar.DragMode = 1
      DoEvents
   End Sub

MORE INFORMATION

Steps to Reproduce Problem

1. Start a new project in Visual Basic. Form1 is created by default.

2. Place a progress bar control on Form1. Change the DragMode property to 1-Automatic.

3. In the Click event of Form1, place the following code:

         Private Sub Form_Click()
            For i = 1 To 10
               ProgressBar1.Value = ProgressBar1.Value + 10
            Next i
         End Sub
   
   

4. Run the project by pressing the F5 key. Click the form, and note that nothing happens. If DragMode was initially set to 0-Manual, then progress is shown until the bar fills.

   Private Sub Form_Click()
      For i = 1 To 10
         UpdateProgress ProgressBar1, ProgressBar1.Value + 10
      Next i
   End Sub