LogonControl.xaml

<UserControl
    x:Class="JmsDemo.LogonControl"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:local="using:JmsDemo"
    xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
    xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
    mc:Ignorable="d"
    d:DesignHeight="300"
    d:DesignWidth="400">
    
    <Grid>
            <Grid.RowDefinitions>
                <RowDefinition  Height="50" />
                <RowDefinition Height="24" />
                <RowDefinition Height= "Auto" />
                <RowDefinition Height="24" />
                <RowDefinition Height="Auto" />
                <RowDefinition Height="Auto" />
            </Grid.RowDefinitions>
            <Grid.ColumnDefinitions>
                <ColumnDefinition Width="200"/>
                <ColumnDefinition Width="160"/>
            </Grid.ColumnDefinitions>
            <TextBlock Grid.Row="0" Text="Login" FontSize="24" Foreground="Black"/>
            <TextBlock Grid.Row="1" Text="Username:" Margin="0"  Foreground="Black"/>
            <TextBox Name="UsernameBox" Grid.ColumnSpan="2" Grid.Row="2" Text="" Foreground="Black" BorderBrush="Black" Width="300" Margin="0"/>
            <TextBlock Grid.Row="3" Text="Password:"  Margin="0" Foreground="Black"/>
            <PasswordBox Grid.Row="4" Grid.ColumnSpan="2" x:Name="PasswordBox" Foreground="Black" BorderBrush="Black" Width="300" Margin="0"/>
            <Button Grid.Row="5" Grid.Column="0" HorizontalAlignment="Right" Content="OK" Width="100" Margin="0" Foreground="Black" BorderBrush="Black" BorderThickness="1" Click="Button_Click"/>
            <Button Grid.Row="5" Grid.Column="1" HorizontalAlignment="Right" Content="Cancel" Foreground="Black" Width="100" Margin="0,0,10,0" BorderBrush="Black" BorderThickness="1" Click="Cancel_Click"/>
 
    </Grid>
</UserControl>