Question

I was hoping for some help with my backgroundworker as I just cant get it to work. Basically I have a backgroundworker which does a few tasks but I’m trying to implement a progress bar and a label. I’m going to set the maximum value of the progress bar to 10 and then have it updating as I move with each task, also I’m thinking of a label with the progress bar which will display the progress ie

Pb value = 2
20% completed

Pb value = 6
60% completed

and so on.

So far I have this for the coding.

Update* Thanks lars fr your help.

So just a quick question would the do work event be like so?

Private Sub BGWorker_DoWork(ByVal sender As Object, _
                            ByVal e As DoWorkEventArgs) _
                            Handles BGWorker.DoWork
  For i as Integer = 1 to 2
    'My task code 1
    BGWorker.ReportProgress(i)
  Next

 For i as Integer = 3 to 4
    'My task code 2
    BGWorker.ReportProgress(i)
  Next

 For i as Integer = 5 to 6
    'My task code 3
    BGWorker.ReportProgress(i)
  Next

 For i as Integer = 7 to 8
    'My task code 4
    BGWorker.ReportProgress(i)
  Next

 For i as Integer = 9 to 10
    'My task code 5
    BGWorker.ReportProgress(i)
  Next
End Sub

Answer 1

Instead of trying to set the progress bar value in DoWork (which isn’t running on the UI thread), you need to have the BackGroundWorker “report” it’s progress:

Private Sub BGWorker_DoWork(ByVal sender As Object, _
                            ByVal e As DoWorkEventArgs) _
                            Handles BGWorker.DoWork
  For i as Integer = 1 to 10
    BGWorker.ReportProgress(i)
  Next
End Sub

Then in your ProgressChanged event, you can set the value of the Progress bar:

Private Sub BGWorker_ProgressChanged(ByVal sender As Object, _
                                     ByVal e As ProgressChangedEventArgs) _
                                     Handles BGWorker.ProgressChanged
  Me.Pb1.Value = e.ProgressPercentage
End Sub