WPF - Create Buttons in a Grid Programatically

Class MainWindow

    Private Sub Button_Click(sender As Object, e As RoutedEventArgs)
        Dim counter As Integer = 1

        Dim rowDict As New Dictionary(Of Integer, RowDefinition)
        Dim colDict As New Dictionary(Of Integer, ColumnDefinition)
        Dim maxRows As Integer = rowSlider.Value
        Dim maxCols As Integer = colSlider.Value

        rowDict.Clear()
        colDict.Clear()
        Panel.RowDefinitions.Clear()
        Panel.ColumnDefinitions.Clear()
        Panel.Children.Clear()
        Panel.UpdateLayout()

        Panel.Width = xcontainer.ActualWidth - 8
        Panel.Height = ycontainer.ActualHeight - 8

        For i As Integer = 0 To maxRows - 1

            If Not rowDict.ContainsKey(i) Then
                Dim rd As New RowDefinition()
                rd.Height = New GridLength(Panel.ActualHeight / maxRows)
                Panel.RowDefinitions.Add(rd)
                rowDict.Add(i, rd)
            End If

            For j As Integer = 0 To maxCols - 1

                If Not colDict.ContainsKey(j) Then
                    Dim cd As New ColumnDefinition()
                    cd.Width = New GridLength(Panel.ActualWidth / maxCols)
                    Panel.ColumnDefinitions.Add(cd)
                    colDict.Add(j, cd)
                End If

                Dim b As Button = CreateButton(counter.ToString())

                AddHandler b.Click, AddressOf DynButtonClicked

                Grid.SetColumn(b, j)
                Grid.SetRow(b, i)

                Panel.Children.Add(b)

                counter += 1
            Next
        Next

        Panel.UpdateLayout()

    End Sub

    Private Function CreateButton(text As String)
        Dim b As New Button
        b.Tag = text
        'b.Margin = New Thickness(2)
        Dim cc As New ContentControl()
        Dim vb As New Viewbox()
        Dim tb As New TextBlock(New Run(text))
        vb.Child = tb
        cc.Content = vb
        b.Content = cc
        b.HorizontalAlignment = Windows.HorizontalAlignment.Stretch
        b.VerticalAlignment = Windows.VerticalAlignment.Stretch
        Return b
    End Function

    Private Sub DynButtonClicked(sender As Object, e As RoutedEventArgs)
        Try
            source.Text = "You clicked " & sender.Tag.ToString()
        Catch ex As Exception

        End Try
    End Sub

    Private Sub Panel_SizeChanged(sender As Object, e As SizeChangedEventArgs)
        If Not IsInitialized Then Return

        Panel.Width = xcontainer.ActualWidth - 8
        Panel.Height = ycontainer.ActualHeight - 8

        Button_Click(doit, New RoutedEventArgs())


    End Sub

    Private Sub rowSlider_ValueChanged(sender As Object, e As RoutedPropertyChangedEventArgs(Of Double)) Handles rowSlider.ValueChanged
        If Not IsInitialized Then Return
        Button_Click(doit, New RoutedEventArgs())

    End Sub

    Private Sub colSlider_ValueChanged(sender As Object, e As RoutedPropertyChangedEventArgs(Of Double)) Handles colSlider.ValueChanged
        If Not IsInitialized Then Return
        Button_Click(doit, New RoutedEventArgs())

    End Sub

    '<Window x:Class="MainWindow"
    '    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    '    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    '    Title="MainWindow" Height="350" Width="525" SizeChanged="Panel_SizeChanged" >
    '    <Grid Background="{DynamicResource {x:Static SystemColors.ActiveCaptionBrushKey}}" HorizontalAlignment="Stretch" VerticalAlignment="Stretch">
    '        <Grid.ColumnDefinitions >
    '            <ColumnDefinition x:Name="xcontainer"></ColumnDefinition>
    '        </Grid.ColumnDefinitions>
    '        <Grid.RowDefinitions>
    '            <RowDefinition x:Name="ycontainer" Height="60*"></RowDefinition>
    '            <RowDefinition Height="30*"/>
    '            <RowDefinition Height="10*"/>
    '        </Grid.RowDefinitions>
    '        <Grid x:Name="Panel" Margin="4" HorizontalAlignment="Stretch" VerticalAlignment="Stretch" />
    '        <Grid Grid.Row="1">
    '            <Grid.RowDefinitions>
    '                <RowDefinition />
    '                <RowDefinition />
    '            </Grid.RowDefinitions>
    '            <Grid.ColumnDefinitions>
    '                <ColumnDefinition />
    '                <ColumnDefinition />
    '            </Grid.ColumnDefinitions>
    '            <Button Margin="4" Grid.Column="1" Grid.RowSpan="2" Click="Button_Click" x:Name="doit" >
    '                <ContentControl>
    '                    <Viewbox>
    '                        <TextBlock Text="Update" />
    '                    </Viewbox>
    '                </ContentControl>
    '            </Button>
    '            <Slider x:Name="rowSlider" Minimum="1" Maximum="10" Value="4" Grid.Row="0" Grid.Column="0" SmallChange="1" Cursor="SizeWE"  />
    '            <Slider x:Name="colSlider" Minimum="1" Maximum="10" Value="4" Grid.Row="1" Grid.Column="0" SmallChange="1" Cursor="SizeWE" />
    '        </Grid>
    '        <Label Grid.Row="2" >
    '            <ContentControl>
    '                <Viewbox>
    '                    <TextBlock Text="You Clicked:" x:Name="source"></TextBlock>
    '                </Viewbox>
    '            </ContentControl>
    '        </Label>
    '    </Grid>
    '</Window>

End Class