ConfirmationDialog.xaml

<Window x:Class="PC2MQTT.ConfirmationDialog"
        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:PC2MQTT"
        mc:Ignorable="d"
        Title="ConfirmationDialog" Height="209" Width="354"
        xmlns:materialDesign="http://materialdesigninxaml.net/winfx/xaml/themes"
        TextElement.Foreground="{DynamicResource MaterialDesign.Brush.Foreground}"
        Background="{DynamicResource MaterialDesign.Brush.Background}"
        TextElement.FontWeight="Regular"
        TextElement.FontSize="12"
        FontFamily="{materialDesign:MaterialDesignFont}"    
        TextOptions.TextFormattingMode="Ideal"
        TextOptions.TextRenderingMode="Auto">
    <Grid>
        <TextBlock x:Name="txtMessage" Text="Are you sure?" VerticalAlignment="Center" HorizontalAlignment="Center"/>
        <StackPanel Orientation="Horizontal" HorizontalAlignment="Center" VerticalAlignment="Bottom" Margin="0,0,0,20">
            <Button x:Name="btnOk" Content="OK" Margin="5" Width="100" Click="btnOk_Click"/>
            <Button x:Name="btnCancel" Content="Cancel" Margin="5" Width="100" Click="btnCancel_Click"/>
        </StackPanel>
    </Grid>
</Window>