AvaloniaProject/ApplicationAvalonia/Views/AuthView.axaml

<UserControl xmlns="https://github.com/avaloniaui"
             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"
             mc:Ignorable="d" d:DesignWidth="800" d:DesignHeight="450"
			 xmlns:vm="clr-namespace:ApplicationAvalonia.ViewModels"			 
			 x:DataType="vm:AuthViewModel"
             x:Class="ApplicationAvalonia.Views.AuthView"
			 >

	<DockPanel VerticalAlignment="Center" HorizontalAlignment="Center">

		<StackPanel Orientation="Vertical">
      
      <TextBlock Text="Авторизация" TextAlignment="Center" FontSize="24" />

			<TextBox Watermark="Логин" Text="{Binding Login}" MinWidth="200"/>
			
			<TextBox Watermark="Пароль" Text="{Binding Password}" MinWidth="200" PasswordChar="*"/>

      <TextBlock Text="{Binding Message}" HorizontalAlignment="Center" Foreground="Red"/>

      <Button HorizontalAlignment="Center" Command="{Binding ButtonClickCommand}">Авторизаия</Button>

      <Button HorizontalAlignment="Center" Command="{Binding RegBtnCommand}">Регистрация</Button>
      			
		</StackPanel>
		
	</DockPanel>
	
</UserControl>