<Window x:Class="Windows.CenterScreen"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    Title="CenterScreen" Height="300" Width="300"
    >
  <Button Margin="15" Click="cmdCenter_Click">Center Me</Button>
</Window>
