Visual Basic

Dim client As New System.Net.WebClient
client.Encoding = System.Text.Encoding.UTF8
Dim sourceString As String = client.DownloadString(page)

I'm trying to work with 3 progress bars where one fill another. Is associated to treenodes in treeview. When research precess is completed with each nodes at certain level, need be filling the progressbar associated to parent node. But I cant make to work correctly. I need help to understand the logic.

Private Sub AtualizaSubcategorias(ByVal execucao As BackgroundWorker)

    Dim pbar_step_n2 As Double = 0, pbar_total_n2 As Double = 0
    Dim pbar_step_n3 As Double = 0, pbar_total_n3 As Double = 0
    Dim pbar_step_n4 As Double = 0, pbar_total_n4 As Double = 0
    Dim pbar_alvo As String = "", menos3 As String

    '********************** TREEVIEW TEMPORÁRIA *************************
    Dim tree_temp As New TreeView
    'clona nodes da tree_menu
    Dim n As New TreeNode
    n = tree_menu.Nodes(0).Clone
    tree_temp.Nodes.Add(n)
    '********************************************************************

    '********************** SUBCATEGORIAS *******************************

    '---------------- NÍVEL 2 (FILHOS)

    pbar_alvo = "n2" 'define o progressbar da vez

    menos3 = pbar_alvo & "|@|" & "100"
    execucao.ReportProgress(-3, menos3)

    pbar_total_n2 = 0
    pbar_step_n2 = (pbar_n2.Maximum / categoriasPARAatualizar.Count)

    For Each n2 As TreeNode In tree_temp.Nodes(0).Nodes 'n1.Nodes 'filhas das principais

        If (execucao.CancellationPending = True) Then Exit For

        If categoriasPARAatualizar.Contains(n2.Tag.ToString) Then
            Dim catTitulo = Split(n2.Text.ToString, "{")
            execucao.ReportProgress(-1, catTitulo(0).ToUpper)
            Capturador(n2.Tag.ToString, 2, n2)
            If pbar_total_n2 >= pbar_n2.Maximum Then
                execucao.ReportProgress(pbar_n2.Maximum, pbar_alvo)
            Else

            End If

            '---------------- NÍVEL 3 (NETOS)

            pbar_alvo = "n3" 'define o progressbar da vez
            If n2.Nodes.Count = 0 Then
                menos3 = pbar_alvo & "|@|" & categoriasPARAatualizar.Count
                execucao.ReportProgress(-3, menos3)
                execucao.ReportProgress(pbar_n3.Maximum, pbar_alvo)
                pbar_total_n2 = pbar_total_n2 + pbar_step_n2
            Else
                menos3 = pbar_alvo & "|@|" & n2.Nodes.Count
                execucao.ReportProgress(-3, menos3)
                pbar_total_n3 = 0
                pbar_step_n3 = (pbar_step_n2 / n2.Nodes.Count)
                For Each n3 As TreeNode In n2.Nodes 'netas das principais
                    If (execucao.CancellationPending = True) Then Exit For
                    Capturador(n3.Tag.ToString, 2, n3)
                    If pbar_total_n3 >= pbar_n3.Maximum Then
                        execucao.ReportProgress(pbar_n3.Maximum, pbar_alvo)
                        pbar_total_n2 = pbar_total_n2 + pbar_step_n2
                    Else

                    End If

                    '---------------- NÍVEL 4 (BISNETOS)

                    pbar_alvo = "n4" 'define o progressbar da vez
                    If n3.Nodes.Count = 0 Then
                        menos3 = pbar_alvo & "|@|" & "100"
                        execucao.ReportProgress(-3, menos3)
                        execucao.ReportProgress(pbar_n4.Maximum, pbar_alvo)
                        pbar_total_n3 = pbar_total_n3 + pbar_step_n3
                    Else
                        menos3 = pbar_alvo & "|@|" & n3.Nodes.Count
                        execucao.ReportProgress(-3, menos3)
                        pbar_total_n4 = 0
                        pbar_step_n4 = (pbar_step_n3 / n3.Nodes.Count)
                        For Each n4 As TreeNode In n3.Nodes 'bisnetas das principais
                            If (execucao.CancellationPending = True) Then Exit For
                            Capturador(n4.Tag.ToString, 2, n4)
                            pbar_total_n4 = pbar_total_n4 + pbar_step_n4
                            If pbar_total_n4 >= pbar_n4.Maximum Then
                                execucao.ReportProgress(pbar_n4.Maximum, pbar_alvo)
                                pbar_total_n3 = pbar_total_n3 + pbar_step_n3
                            Else
                                execucao.ReportProgress(pbar_total_n4, pbar_alvo)
                            End If
                        Next 'n4
                    End If 'n4
                Next 'n3
            End If 'n3
        End If
    Next
    '**********************************************************************
    execucao.ReportProgress(-2, tree_temp)
End Sub

Private Sub subcategorias_BckGrndWorker_ProgressChanged(sender As Object, e As ProgressChangedEventArgs) Handles subcategorias_BckGrndWorker.ProgressChanged

    '------------ COMANDOS

    If e.ProgressPercentage < 0 Then
        Select Case e.ProgressPercentage
            Case -1 'alterar label
                lbl_categoria.Text = e.UserState 'atualiza label
            Case -2 'obter a tree temporaria, clonar para a tree_menu e apresentar-la
                tree_menu.Nodes.Clear()
                tree_menu = e.UserState
                Panel1.Controls.Add(tree_menu)
                tree_menu.Dock = DockStyle.Fill
                tree_menu.ExpandAll()
            Case -3 'definir o valor maximo do progressbar
                Dim splt = Split(e.UserState, "|@|")
                If UCase(splt(0)) = "N2" Then
                    pbar_n2.Maximum = Int(splt(1))
                ElseIf UCase(splt(0)) = "N3" Then
                    pbar_n3.Maximum = Int(splt(1))
                ElseIf UCase(splt(0)) = "N4" Then
                    pbar_n4.Maximum = Int(splt(1))
                End If
        End Select
    End If

    '------------ PROGRESSBAR

    If e.ProgressPercentage > 0 Then
        Select Case UCase(e.UserState)
            Case "N2"
                'atualiza barra de progresso
                pbar_n2.Value = e.ProgressPercentage
                If pbar_n2.Value = pbar_n2.Maximum Then pbar_n2.Value = 0
            Case "N3"
                'atualiza barra de progresso
                pbar_n3.Value = e.ProgressPercentage
                If pbar_n3.Value = pbar_n3.Maximum Then pbar_n3.Value = 0
            Case "N4"
                'atualiza barra de progresso
                pbar_n4.Value = e.ProgressPercentage
                If pbar_n4.Value = pbar_n4.Maximum Then pbar_n4.Value = 0
        End Select
    End If
End Sub

Sub update_available_room()
        Try
        lvroom.BeginUpdate()
        For Each L As ListViewItem In lvroom.Items
            Dim mycommand As MySqlCommand = conn.open.CreateCommand
            Dim query1 = "SELECT room.*,roomtype.* FROM room, roomtype WHERE room.RoomType=roomtype.RoomType AND RoomNo='" & L.ImageKey & "'"
            mycommand.CommandText = query1
            Dim baca1 As MySqlDataReader = mycommand.ExecuteReader
            If baca1.Read() Then
                Dim NoKamar As String = baca1("RoomNo")
                Dim str As String
                If Len(NoKamar) = 1 Then
                    str = "00" & NoKamar
                ElseIf Len(NoKamar) = 2 Then
                    str = "0" & NoKamar
                Else
                    str = NoKamar
                End If
                If baca1("Available") = True And baca1("Status") = False Then

                    L.ImageList.Images.RemoveByKey(L.ImageKey)
                    Dim newbitmap As Bitmap = My.Resources.bulat_hijau
                    Dim g As Graphics
                    g = Graphics.FromImage(newbitmap)
                    g.DrawString(str, New Font("Arial", 65, FontStyle.Bold), New SolidBrush(Color.Yellow), New Point(85, 50))
                    g.DrawString("______________________", New Font("Arial", 65, FontStyle.Bold), New SolidBrush(Color.White), New Point(0, 80))
                    g.DrawString(baca1("Singkatan"), New Font("Arial", 65, FontStyle.Bold), New SolidBrush(Color.White), New Point(82, 170))
                    L.Text = "EMPTY"
                    L.Font = New Font("Arial", 12, FontStyle.Bold)
                    L.ImageList.Images.Add(NoKamar, newbitmap)

                ElseIf baca1("Available") = False And baca1("Status") = False Then

                    L.ImageList.Images.RemoveByKey(L.ImageKey)
                    Dim newbitmap As Bitmap = My.Resources.bulat_purple
                    Dim g As Graphics
                    g = Graphics.FromImage(newbitmap)
                    g.DrawString(str, New Font("Arial", 65, FontStyle.Bold), New SolidBrush(Color.Yellow), New Point(85, 50))
                    g.DrawString("______________________", New Font("Arial", 65, FontStyle.Bold), New SolidBrush(Color.White), New Point(0, 80))
                    g.DrawString(baca1("Singkatan"), New Font("Arial", 65, FontStyle.Bold), New SolidBrush(Color.White), New Point(82, 170))
                    L.Text = "N/A"
                    L.Font = New Font("Arial", 12, FontStyle.Bold)
                    L.ImageList.Images.Add(NoKamar, newbitmap)

                End If
            End If
                baca1.Close()
            lvroom.Refresh()
        Next
        conn.close()
        lvroom.EndUpdate()
        Catch ex As Exception
            MsgBox(ex.Message)
        Finally
        conn.close()
        End Try
    End Sub

but I am getting err:

Index was out of range. Must be non-negative and less than the size of the collection. Parameter name: index

Public Class LinerTypesCollection
        Inherits System.Collections.ObjectModel.ObservableCollection(Of String)

        Public Sub New(ByVal IsMetric As Boolean)

           ' Do stuff
           
        End Sub
   End Class

Namespace Base.Controls.Panels
    Partial Public Class StartPanel
        Public Sub New (ByVal bool as Boolean, Optional ByVal bool2 as Boolean = false)

            ' This works.
            cmbBox.ItemsSource = New LinerTypesCollection(False)
        End Sub
    End Class
End Namespace

Namespace Base.Utilities
    Public Class ConnectionOption
        Public Sub New (ByVal IsMetric as Boolean)

            ' This does not work. I cannot get IntelliSense to acknowledge that LinerTypesCollection exists.
            cmbBox.ItemsSource = New LinerTypesCollection(False)
        End Sub
    End Class
End Namespace