VB Net Background Worker freeze when updating the GridView

[hakim_8]

I have some problem with my code, i can fetching data from database perfectly fine without any freezing, but after the fetching finish and i want to add the fetched data into grid view, the program will freeze even though i already input the code inside background worker.

Here is the code for table declaration, i use DevExpress Grid Data if you wondering about it.

Dim Table1 As DataTable 
Dim ItemCode As String = ""
Dim ItemName As String = ""
Dim BrandName As String = ""
Dim FamilyName As String = ""
Dim SubFamilyName As String = ""

Sub loadtabel()
    Table1 = New DataTable("myTable")

    Table1.Columns.Add(CreateColumn("ItemCode", "str"))
    Table1.Columns.Add(CreateColumn("ItemName", "str"))
    Table1.Columns.Add(CreateColumn("BrandName", "str"))
    Table1.Columns.Add(CreateColumn("Quantity", "int"))
    Table1.Columns.Add(CreateColumn("UOM", "str"))
    Table1.Columns.Add(CreateColumn("FamilyName", "str"))
    Table1.Columns.Add(CreateColumn("SubFamilyName", "str"))

    dgvTabel.DataSource = Table1


End Sub

Here is my function to starting my BackgroundWorker

Sub LoadData(ByVal varItemCode As String, ByVal varItemName As String, ByVal varBrandName As String, ByVal varFamilyName As String, ByVal varSubFamilyName As String)
        loadtabel() 

        If BackgroundWorker1.IsBusy Then
            Exit Sub
        End If

        ItemCode = ""
        ItemName = ""
        BrandName = ""
        FamilyName = ""
        SubFamilyName = ""

        If varItemCode <> "" Then ItemCode = varItemCode
        If varItemName <> "" Then ItemName = varItemName
        If varBrandName <> "" Then BrandName = varBrandName
        If varFamilyName <> "" Then FamilyName = varFamilyName
        If varSubFamilyName <> "" Then SubFamilyName = varSubFamilyName

        pbLoading.Visible = True
        lblLoading.Text = "Fetching Data, Please Wait..."

        BackgroundWorker1.RunWorkerAsync()

End Sub

And here is my BackgroundWorker query, in here i also do the fetching data. fetching data from database itself takes up to 11 Second. About more than 20.000 Data. but since i use Background Worker it fetching smoothly without freezing.

Private Sub bgwSuburbs_DoWork(ByVal sender As System.Object, ByVal e As System.ComponentModel.DoWorkEventArgs) Handles BackgroundWorker1.DoWork


        Dim request As HttpWebRequest
            Dim reader As StreamReader
            Dim postData As String = ""

            Dim UrlPrefix = "http://" & My.Settings.SharedConnection & ":" & My.Settings.SharedURLPort
            request = DirectCast(WebRequest.Create(UrlPrefix & "/hotraxpos/item_list.php"), HttpWebRequest)

        postData = "itemcode=" & ItemCode &
                               "&itemname=" & ItemName &
                               "&brandname=" & BrandName &
                               "&familyname=" & FamilyName &
                               "&subfamilyname=" & SubFamilyName &
                               "&device_data=HC ALL IN ONE"

        request.Method = "POST"

            Dim byteArray As Byte() = Encoding.UTF8.GetBytes(postData)

            request.ContentType = "application/x-www-form-urlencoded"
            request.ContentLength = byteArray.Length

            Dim dataStream As Stream = request.GetRequestStream()
            dataStream.Write(byteArray, 0, byteArray.Length)
        dataStream.Close()

           Dim response As WebResponse = request.GetResponse()
            reader = New StreamReader(response.GetResponseStream())

            Dim rawresp As String
            rawresp = reader.ReadToEnd()

            Dim array As JArray = JArray.Parse(rawresp)

       'IF I EXCLUDE CODE FROM HERE, THE BACKGROUND WORKER WORK NORMALLY WITHOUT FREEZING
        Me.Invoke(Sub()

                      For Each item As JObject In array
                          Dim status As String = If(item("Status") Is Nothing, "", item("Status").ToString())
                          Dim Keterangan As String = If(item("Keterangan") Is Nothing, "", item("Keterangan").ToString())

                          Console.WriteLine("Keterangan: " & Keterangan)

                          If status = "SUCCESS" Then
                              Dim varItemCode = If(item("ItemCode") Is Nothing, 0, item("ItemCode").ToString)
                              Dim varItemName = If(item("ItemName") Is Nothing, 0, item("ItemName").ToString)
                              Dim varBrandName = If(item("BrandName") Is Nothing, 0, item("BrandName").ToString)
                              Dim varQuantity = If(item("Quantity") Is Nothing, 0, Val(item("Quantity").ToString))
                              Dim varUOM = If(item("UOM") Is Nothing, 0, item("UOM").ToString)
                              Dim varFamilyName = If(item("FamilyName") Is Nothing, 0, item("FamilyName").ToString)
                              Dim varSubFamilyName = If(item("SubFamilyName") Is Nothing, 0, item("SubFamilyName").ToString)

                              Dim Row1 As DataRow
                              Row1 = Table1.NewRow()

                              Row1.Item("ItemCode") = varItemCode
                              Row1.Item("ItemName") = varItemName
                              Row1.Item("BrandName") = varBrandName
                              Row1.Item("Quantity") = varQuantity
                              Row1.Item("UOM") = varUOM
                              Row1.Item("FamilyName") = varFamilyName
                              Row1.Item("SubFamilyName") = varSubFamilyName

                              Table1.Rows.Add(Row1)
                          End If
                      Next
                      dgvTabel.DataSource = Table1
                  End Sub)


    End Sub

Private Sub bgwSuburbs_RunWorkerCompleted(ByVal sender As System.Object, ByVal e As System.ComponentModel.RunWorkerCompletedEventArgs) Handles BackgroundWorker1.RunWorkerCompleted 
    pbLoading.Visible = False

    lblLoading.Text = "Done"
End Sub

Just like i mention above, if i remove code at Me.Invoke(Sub() inside of Background Worker DoWork it work perfectly without freezing, but also without any data showing too...
please help, i just need to know how to fill the datagridview too without freezing with background worker. how do i do this ?