Threading and updating form question.

[Roger]

I have a function that is currently wrapped up in a Class so I can pass a
variable to it.

This function is going to be threaded out and I would like the class
function to be able to update a control on my form. (Treeview).

Is this possible and how do I do it?
Here is a simplisitc overview of what I am doing...
Public Class Form1

Public Sub Button1_Click
GetDirs()
end sub

Public Sub GetDirs()
Dim dir As String
Dim i As Integer = 1
Dim dirs() As String = Directory.GetDi rectories("P:\" )
For Each dir In dirs
Dim t As System.Threadin g.Thread
dim oListView as new SubClass1
t = New System.Threadin g.Thread(Addres sOf
oListView.FileL istToListView)
oListView.sFold er = dir
'''' I thought by passing the Treeview1 control I could update
it in the class...
oListView.tView = TreeView1
t.Start()
i += 1
ProgressBar1.Va lue = 100 * (i / CLng(UBound(dir s)))
Next
End Sub

end class

Public Class SubClass1
Public sFolder as string
public tView as treeview
public sub FileListToListV iew
'''' **** Here is where I want to update the Form1.treeview1 control
tview.nodes.add (sFolder)
end sub
end class

[Jorge Serrano [MVP VB]]

Hi Roger,

If I have understand your question, you should use something similar to:
[...]
dim oListView as new SubClass1
oListView.tView = Me.Treeview1
t = New System.Threadin g.Thread(Addres sOf oListView.FileL istToListView)
[...]

I hope that helps.

King Regards,

Jorge Serrano Pérez
MVP VB.NET

"Roger" wrote:

I have a function that is currently wrapped up in a Class so I can pass a
variable to it.

This function is going to be threaded out and I would like the class
function to be able to update a control on my form. (Treeview).

Is this possible and how do I do it?
Here is a simplisitc overview of what I am doing...
Public Class Form1

Public Sub Button1_Click
GetDirs()
end sub

Public Sub GetDirs()
Dim dir As String
Dim i As Integer = 1
Dim dirs() As String = Directory.GetDi rectories("P:\" )
For Each dir In dirs
Dim t As System.Threadin g.Thread
dim oListView as new SubClass1
t = New System.Threadin g.Thread(Addres sOf
oListView.FileL istToListView)
oListView.sFold er = dir
'''' I thought by passing the Treeview1 control I could update
it in the class...
oListView.tView = TreeView1
t.Start()
i += 1
ProgressBar1.Va lue = 100 * (i / CLng(UBound(dir s)))
Next
End Sub

end class

Public Class SubClass1
Public sFolder as string
public tView as treeview
public sub FileListToListV iew
'''' **** Here is where I want to update the Form1.treeview1 control
tview.nodes.add (sFolder)
end sub
end class

[Imran Koradia]

Use delegates:

Delegate Sub TreeViewAddNode Delegate(ByVal sNode As String)
Private AddNode As New TreeViewAddNode Delegate(Addres sOf AddTvNode)

Private Sub AddTvNode(ByVal sNode As String)
TreeView1.Nodes .Add(sNode)
End Sub

Then use the Invoke method to marshal the call from the executing thread to
the main UI thread:

TreeView1.Invok e(AddNode, New Object() {"Node1"})
hope that helps..
Imran.

"Roger" <da*****@netins .net> wrote in message
news:e3******** ******@TK2MSFTN GP09.phx.gbl...

I have a function that is currently wrapped up in a Class so I can pass a
variable to it.

This function is going to be threaded out and I would like the class
function to be able to update a control on my form. (Treeview).

Is this possible and how do I do it?
Here is a simplisitc overview of what I am doing...
Public Class Form1

Public Sub Button1_Click
GetDirs()
end sub

Public Sub GetDirs()
Dim dir As String
Dim i As Integer = 1
Dim dirs() As String = Directory.GetDi rectories("P:\" )
For Each dir In dirs
Dim t As System.Threadin g.Thread
dim oListView as new SubClass1
t = New System.Threadin g.Thread(Addres sOf
oListView.FileL istToListView)
oListView.sFold er = dir
'''' I thought by passing the Treeview1 control I could update
it in the class...
oListView.tView = TreeView1
t.Start()
i += 1
ProgressBar1.Va lue = 100 * (i / CLng(UBound(dir s)))
Next
End Sub

end class

Public Class SubClass1
Public sFolder as string
public tView as treeview
public sub FileListToListV iew
'''' **** Here is where I want to update the Form1.treeview1 control
tview.nodes.add (sFolder)
end sub
end class

[Roger]

When I add this I get the following error....

Additional information: The action being performed on this control is being
called from the wrong thread. You must marshal to the correct thread using
Control.Invoke or Control.BeginIn voke to perform this action.

Roger

"Jorge Serrano [MVP VB]"
<NO************ *******@NOQUIER OSPAMportalvbNO SPAM.com.NOQUIE ROSPAM> wrote in
message news:B5******** *************** ***********@mic rosoft.com...

Hi Roger,

If I have understand your question, you should use something similar to:
[...]
dim oListView as new SubClass1
oListView.tView = Me.Treeview1
t = New System.Threadin g.Thread(Addres sOf oListView.FileL istToListView)
[...]

I hope that helps.

King Regards,

Jorge Serrano Pérez
MVP VB.NET

"Roger" wrote:

I have a function that is currently wrapped up in a Class so I can pass a variable to it.

This function is going to be threaded out and I would like the class
function to be able to update a control on my form. (Treeview).

Is this possible and how do I do it?
Here is a simplisitc overview of what I am doing...
Public Class Form1

Public Sub Button1_Click
GetDirs()
end sub

Public Sub GetDirs()
Dim dir As String
Dim i As Integer = 1
Dim dirs() As String = Directory.GetDi rectories("P:\" )
For Each dir In dirs
Dim t As System.Threadin g.Thread
dim oListView as new SubClass1
t = New System.Threadin g.Thread(Addres sOf
oListView.FileL istToListView)
oListView.sFold er = dir
'''' I thought by passing the Treeview1 control I could update it in the class...
oListView.tView = TreeView1
t.Start()
i += 1
ProgressBar1.Va lue = 100 * (i / CLng(UBound(dir s)))
Next
End Sub

end class

Public Class SubClass1
Public sFolder as string
public tView as treeview
public sub FileListToListV iew
'''' **** Here is where I want to update the Form1.treeview1 control tview.nodes.add (sFolder)
end sub
end class

[Jon Skeet [C# MVP]]

Roger <da*****@netins .net> wrote:

I have a function that is currently wrapped up in a Class so I can pass a
variable to it.

This function is going to be threaded out and I would like the class
function to be able to update a control on my form. (Treeview).

See http://www.pobox.com/~skeet/csharp/t...winforms.shtml

--
Jon Skeet - <sk***@pobox.co m>
http://www.pobox.com/~skeet
If replying to the group, please do not mail me too