Visual Basic

    Private Delegate Sub AddItemToListViewDelegate(ByVal item As String)
    Private Delegate Sub ChangeSubItemDelegate(ByVal index As Integer, ByVal item As String)
 
    Private t1 As Thread
    Private t2 As Thread
 
    Private Const MAXITEMS As Long = 20
 
    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        'AddItems()
        ListView1.Items.Clear()
 
        t1 = New Thread(New ThreadStart(AddressOf AddItems))
        t1.Start()
        Thread.Sleep(100)
        t2 = New Thread(New ThreadStart(AddressOf RandomSubItems))
        t2.Start()
    End Sub
 
    Private Sub AddItemToListView(ByVal item As String)
        If ListView1.InvokeRequired Then
            Dim d As New AddItemToListViewDelegate(AddressOf AddItemToListView)
            Invoke(d, New String() {item})
        Else
            Dim newItem As New ListViewItem(item)
            newItem.SubItems.Add("---")
            ListView1.Items.Add(newItem)
            Application.DoEvents()
        End If
    End Sub
 
    Private Sub ChangeSubItem(ByVal index As Integer, ByVal item As String)
        Try
            If ListView1.InvokeRequired Then
                Dim d As New ChangeSubItemDelegate(AddressOf ChangeSubItem)
                Invoke(d, New Object() {index, item})
            Else
                If ListView1.Items.Count > index Then
                    ListView1.Items(index).SubItems(1).Text = item
                    Application.DoEvents()
                End If
            End If
        Catch
        End Try
    End Sub
 
    Private Sub AddItems()
        Dim x As Long
 
        While x < MAXITEMS
            Try
                AddItemToListView(String.Format("Item #{0}", x))
                x = x + 1
            Catch ex As ThreadAbortException
                Exit While
            End Try
        End While
    End Sub
 
    Private Sub RandomSubItems()
        Dim RNG As New Random
        Dim x As Long
 
        While True
            Try
                ChangeSubItem(RNG.Next(0, MAXITEMS), RNG.Next(0, 1000).ToString())
            Catch ex As ThreadAbortException
                Exit While
            End Try
            ' This little sleep has to be in there for some reason.
            ' The form won't update properly without it!
            Thread.Sleep(1)
        End While
    End Sub
 
    Private Sub Form1_Closing(ByVal sender As Object, ByVal e As System.ComponentModel.CancelEventArgs) Handles MyBase.Closing
        If t1 Is Nothing Then
            Exit Sub
        End If
        t1.Abort()
        t1.Join()
 
        t2.Abort()
        t2.Join()
    End Sub

    Private Delegate Sub AddItemToListViewDelegate(ByVal item As String)
    Private Delegate Sub ChangeSubItemDelegate(ByVal index As Integer, ByVal item As String)
 
    Private t1 As Thread
    Private t2 As Thread
 
    Private Sub Form1_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles MyBase.Load
        Module1.myForm = Me
    End Sub
 
    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        ListView1.Items.Clear()
        t1 = New Thread(New ThreadStart(AddressOf AddItems))
        t1.Start()
        Thread.Sleep(100)
        t2 = New Thread(New ThreadStart(AddressOf Module1.RandomSubItems))
        t2.Start()
    End Sub
 
    Private Sub AddItemToListView(ByVal item As String)
        If ListView1.InvokeRequired Then
            Dim d As New AddItemToListViewDelegate(AddressOf AddItemToListView)
            Invoke(d, New String() {item})
        Else
            Dim newItem As New ListViewItem(item)
            newItem.SubItems.Add("---")
            ListView1.Items.Add(newItem)
            Application.DoEvents()
        End If
    End Sub
 
    Public Sub ChangeSubItem(ByVal index As Integer, ByVal item As String)
        Try
            If ListView1.InvokeRequired Then
                Dim d As New ChangeSubItemDelegate(AddressOf ChangeSubItem)
                Invoke(d, New Object() {index, item})
            Else
                If ListView1.Items.Count > index Then
                    ListView1.Items(index).SubItems(1).Text = item
                    Application.DoEvents()
                End If
            End If
        Catch
        End Try
    End Sub
 
    Public Sub AddItems()
        Dim x As Long
 
        While x < MAXITEMS
            Try
                AddItemToListView(String.Format("Item #{0}", x))
                x = x + 1
            Catch ex As ThreadAbortException
                Exit While
            End Try
        End While
    End Sub
 
    Private Sub Form1_Closing(ByVal sender As Object, ByVal e As System.ComponentModel.CancelEventArgs) Handles MyBase.Closing
        If t1 Is Nothing Then
            Exit Sub
        End If
        t1.Abort()
        t1.Join()
 
        t2.Abort()
        t2.Join()
    End Sub

Imports System.Threading
 
Module Module1
    Public myForm As Form1
    Public Const MAXITEMS As Long = 20
 
    Public Sub RandomSubItems()
        Dim RNG As New Random
        Dim x As Long
 
        While True
            Try
                myForm.ChangeSubItem(RNG.Next(0, MAXITEMS), RNG.Next(0, 1000).ToString())
            Catch ex As ThreadAbortException
                Exit While
            End Try
            Thread.Sleep(1)
        End While
    End Sub
End Module