ChooseNumberOfScreens.xaml

<Window x:Class="Grouping.ChooseNumberOfScreens"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
        xmlns:local="clr-namespace:Grouping"
        mc:Ignorable="d"
        Title="ChooseNumberOfScreens" Height="300" Width="300">
    <Grid>
        <TextBox x:Name="textBox" HorizontalAlignment="Left" Height="83" Margin="36,70,0,0" TextWrapping="Wrap" VerticalAlignment="Top" Width="216"/>
        <Button x:Name="button" Content="Save" HorizontalAlignment="Left" Margin="106,169,0,0" VerticalAlignment="Top" Width="75" Click="Button_Click"/>

    </Grid>
</Window>