SchoolAvalonia/AVSchool/Views/Add.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="1000" d:DesignHeight="600"
			 xmlns:vm="using:AVSchool.ViewModels"
			       x:DataType="vm:MainWindowViewModel"
             x:Class="AVSchool.Views.Add">

	<Grid>
		<StackPanel Margin="10" Width="980" Height="580" Background="LightBlue">
			<StackPanel Margin="10">
		<StackPanel Orientation="Vertical" HorizontalAlignment="Center">
			<Button Command="{Binding ToData}" HorizontalAlignment="Right" Margin="0,0,0,10">Назад</Button>
			<StackPanel Orientation="Horizontal" HorizontalAlignment="Center" >
				<TextBox Watermark="Фамилия" Width="235" Text="{Binding AddVM.TSurname}"/>
				<TextBox Margin="10,0,0,0" Width="175" Watermark="Имя"  Text="{Binding AddVM.TName}"/>
				<TextBox Margin="10,0,0,0" Width="290" Watermark="Отчество"  Text="{Binding AddVM.TPatronymic}"/>
			</StackPanel>
			<DatePicker Margin="0,10,0,0"  Height="30" SelectedDate="{Binding AddVM.TBirthday}" HorizontalAlignment="Center"/>
			<StackPanel Orientation="Horizontal" Margin="0 10 0 0" HorizontalAlignment="Center">
				<RadioButton Content="Мужской" Margin="0,0,20,0" IsChecked="{Binding AddVM.TGenderM}"/>
				<RadioButton Content="Женский" Margin="0,0,0,0"/>
			</StackPanel>
			<TextBox Watermark="Стаж работы" Margin="0,10,0,0" Text="{Binding AddVM.TExp}"/>
			<TextBox Watermark="mail" Margin="0,10,0,0" Text="{Binding AddVM.TMail}"/>
			<TextBox Watermark="phone" Margin="0,10,0,0" Text="{Binding AddVM.TPhone}"/>
			<StackPanel Orientation="Vertical">
				<ComboBox Margin="0,10,0,0" Width="725" ItemsSource="{Binding AddVM.CollSub}" SelectedItem="{Binding AddVM.SelectSubject}" MaxDropDownHeight="250">
					<ComboBox.ItemTemplate>
						<DataTemplate>
							<TextBlock Text="{Binding Item1}"/>
						</DataTemplate>
					</ComboBox.ItemTemplate>
				</ComboBox>
				<ListBox ItemsSource="{Binding AddVM.CollSubSelect}" Width="720" Height="150" HorizontalAlignment="Center" Margin="0,10,0,0">
					<ListBox.ItemTemplate>
						<DataTemplate>
							<TextBlock Text="{Binding Item1}"/>
						</DataTemplate>
					</ListBox.ItemTemplate>
				</ListBox>
			</StackPanel>
			<StackPanel Orientation="Horizontal" HorizontalAlignment="Center">
				<Button Margin="0,10,0,0" Command="{Binding AddVM.AddNew}" Content="Добавить"/>
			</StackPanel>
		</StackPanel>
		</StackPanel>
		</StackPanel>
	</Grid>

</UserControl>