Member Avatar for darkelflemurian

Hello everyone I have the following situation with the background worker and hope someone can help me with this.

1.- i have a form and in that form I have the background worker. the methods doWork, Progresschanged, Runworklercompleted are in the form.

2.- when i star doWork, it executes a method called Process1 from class AMOUNTS from another class and it works fine, the program does it's work.

3.- the thing is that i have to fill a listbox with each step the program is doing.

4.- in the main form I have a method which is public called LogEvent. in this method is where i update the listbox with the steps of the program.

5.-in Process1, i want to send those steps to the LogEvent which is on form1. but nothing is being shown.

6.- I would apreciate a code as an example, i tried to use InvokeRequired but I dont know how to make it work with methods.

Thanks in advance.

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  • Latest Post Latest Post by darkelflemurian
Member Avatar for Mitja Bonca

How to use a invokeRequired method while you have to invoke a control over threads shows the exmple code with using Delegates bellow:

Private Delegate Sub MyDelegate(msg As String)
Private Sub FillingListBox(value As String)
	If listBox1.InvokeRequired Then
		listBox1.Invoke(New MyDelegate(AddressOf FillingListBox), New Object() {value})
	Else
		listBox1.Items.Add(value)
	End If
End Sub

You call this method when you want to pass the new item to listBox.

Edited by Mitja Bonca because: n/a
Member Avatar for darkelflemurian

Thanks for your response, however what I'm trying to do here is to call a method in the main form from a class that is being executed in the background worker.

I tried to adapt the example you gave me but for some reason its giving errors.

Thanks in advance.

How to use a invokeRequired method while you have to invoke a control over threads shows the exmple code with using Delegates bellow:

Private Delegate Sub MyDelegate(msg As String)
Private Sub FillingListBox(value As String)
	If listBox1.InvokeRequired Then
		listBox1.Invoke(New MyDelegate(AddressOf FillingListBox), New Object() {value})
	Else
		listBox1.Items.Add(value)
	End If
End Sub

You call this method when you want to pass the new item to listBox.

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