Threading & updating controls

Imports System.Threading
Public Class Form1
 
    Delegate Sub lvDelegate()
 
    Private Sub lvThreadMain()
        Debug.Print("Secondary Thread Sleeping...")
        System.Threading.Thread.Sleep(10000) ' this will NOT lock the Form up!
 
        If Me.InvokeRequired Then
            Debug.Print("Invoking UpdateListView")
            Me.Invoke(New lvDelegate(AddressOf UpdateListView))
        End If
    End Sub
 
    ' Update Listview Code
    Private Sub UpdateListView()
        Debug.Print("Sleeping in UpdateListView")
        System.Threading.Thread.Sleep(10000) ' this WILL lock the Form up!
    End Sub
 
    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        Dim lvThread As New Threading.Thread(AddressOf lvThreadMain)
        lvThread.Priority = ThreadPriority.Highest
        lvThread.IsBackground = True
        lvThread.Start()
    End Sub
 
End Class
                                              

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Imports System.Threading
 
Public Class Form1
 
    Dim lvThread As Thread
 
    Delegate Sub lvDelegate(ByVal item As ListViewItem)
    Private performUpdate As New lvDelegate(AddressOf UpdateListView)
 
 
    Private Sub lvThreadMain()
 
        For x As Integer = 0 To 1000
 
            Dim newItem As New ListViewItem
            newItem.Text = x.ToString
            newItem.SubItems.Add(Now.ToLongTimeString())
 
            performUpdate.BeginInvoke(newItem, Nothing, Nothing)
            Thread.Sleep(50)
        Next
 
    End Sub
 
 
    Private Sub UpdateListView(ByVal item As ListViewItem)
 
        If Me.InvokeRequired Then
            Dim d As New lvDelegate(AddressOf UpdateListView)
            Me.Invoke(d, New Object() {item})
        Else
            Me.ListView1.Items.Add(item)
        End If
 
        Debug.WriteLine("Done!")
    End Sub
 
 
    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        lvThread = New Thread(AddressOf lvThreadMain)
        lvThread.Priority = ThreadPriority.Highest
        lvThread.IsBackground = True
        lvThread.Start()
    End Sub
 
End Class

                                              

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