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From: Roidy on 25 May 2010 14:08
OK bear with me while I try to explain :)

I'm writing a program where I need to do a lot of different background
worker tasks and display the progress in a dialog box. So rather than create
a separate dialog for each task I created a class that displays a dialog and
fires off a background worker, what I can't seem to do is pass a dowork
handler sub into the class. This is basically what I've got so far:-

MainForm code:-

........
Dim pBox as New ProgressBox("Test caption")
pBox.ShowDialog()

Sub worksub()
.........
Do background work here
.........
End Sub
........

Class code:-

Public Class ProgressBox
Public Sub New(ByVal txt as String)
InitProgBox()
Me.Label1.text = txt
Me.backgroundworker1.runWorkerAsync()
End Sub

Public Sub InitProgBox()
..........
..........
Code to set up the dialog and background worker
..........
..........
End Sub
End Class

I can happily pass string and other variables in to the class but when I
create a new instance of ProgressBox I need to be able to pass worksub into
it and have it added as the handler of the backgroundworkers DoWork
function. I just can't figure out how to pass worksub into the class along
the lines of:-

Dim pBox as New ProgressBox("Test caption", worksub)


Help please

Robert

From: Tom Shelton on 25 May 2010 14:17
Roidy formulated on Tuesday :
> OK bear with me while I try to explain :)
>
> I'm writing a program where I need to do a lot of different background worker
> tasks and display the progress in a dialog box. So rather than create a
> separate dialog for each task I created a class that displays a dialog and
> fires off a background worker, what I can't seem to do is pass a dowork
> handler sub into the class. This is basically what I've got so far:-
>
> MainForm code:-
>
> .......
> Dim pBox as New ProgressBox("Test caption")
> pBox.ShowDialog()
>
> Sub worksub()
> .........
> Do background work here
> .........
> End Sub
> .......
>
> Class code:-
>
> Public Class ProgressBox
> Public Sub New(ByVal txt as String)
> InitProgBox()
> Me.Label1.text = txt
> Me.backgroundworker1.runWorkerAsync()
> End Sub
>
> Public Sub InitProgBox()
> ..........
> ..........
> Code to set up the dialog and background worker
> ..........
> ..........
> End Sub
> End Class
>
> I can happily pass string and other variables in to the class but when I
> create a new instance of ProgressBox I need to be able to pass worksub into
> it and have it added as the handler of the backgroundworkers DoWork function.
> I just can't figure out how to pass worksub into the class along the lines
> of:-
>
> Dim pBox as New ProgressBox("Test caption", worksub)
>
Dim pBox As New Progressbox ("Test caption", AddressOf workSub)

HTH

--
Tom Shelton


From: Roidy on 25 May 2010 14:36
Thanks Tom, but how do I then get the sub in the class and add it as a
handler? What type will it be?

Public Class ProgressBox
Public Sub New(ByVal txt as String, ???????????????<- How to get it)
InitProgBox()

AddHandler backgroundWorker1.DoWork, ??????????????????????

Me.Label1.text = txt
Me.backgroundworker1.runWorkerAsync()
End Sub
End Sub
End Class

Thanks
rob

>
> Dim pBox As New Progressbox ("Test caption", AddressOf workSub)
>
> HTH
>
> --
> Tom Shelton
>
>
From: Tom Shelton on 25 May 2010 14:44
Roidy formulated on Tuesday :
> Thanks Tom, but how do I then get the sub in the class and add it as a
> handler? What type will it be?
>
> Public Class ProgressBox
> Public Sub New(ByVal txt as String, ???????????????<- How to get it)
> InitProgBox()
>
> AddHandler backgroundWorker1.DoWork, ??????????????????????
>
> Me.Label1.text = txt
> Me.backgroundworker1.runWorkerAsync()
> End Sub
> End Sub
> End Class
>
> Thanks
> rob
>
>>
>> Dim pBox As New Progressbox ("Test caption", AddressOf workSub)
>>
>> HTH
>>
>> -- Tom Shelton
>>
>>

In the class that is creating going to acutally host the event...


Private Sub DoWork (ByVal sender As Object, ByVal e As DoWorkEventArgs)
' do cool stuff
End Sub


''' declaring an instance in the class with the sub
Dim pBox As New ProgressBox("Test Caption", AddressOf DoWork)

'' in the progressBox Class Constructor
Public Sub New(ByVal caption As String, ByVal workSub As DoWorkEventHandler)
' do init
' add the handler
AddHandler _backgroundWorker.DoWork, workSub
End Sub

HTH

--
Tom Shelton


From: Roidy on 25 May 2010 15:28
Thanks Tom that did it. Works perfectly.

Robert


"Tom Shelton" <tom_shelton(a)comcast.invalid> wrote in message
news:hth5r3$jo3$1(a)news.eternal-september.org...

>
> In the class that is creating going to acutally host the event...
>
>
> Private Sub DoWork (ByVal sender As Object, ByVal e As DoWorkEventArgs)
> ' do cool stuff
> End Sub
>
>
> ''' declaring an instance in the class with the sub
> Dim pBox As New ProgressBox("Test Caption", AddressOf DoWork)
>
> '' in the progressBox Class Constructor
> Public Sub New(ByVal caption As String, ByVal workSub As
> DoWorkEventHandler)
> ' do init
> ' add the handler
> AddHandler _backgroundWorker.DoWork, workSub
> End Sub
>
> HTH
>
> --
> Tom Shelton
>
>
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