AvaloniaCatBase/AvaloniaApplicationBase/Views/AddCatPage.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:vm="using:AvaloniaApplicationBase.ViewModels"
             xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
             mc:Ignorable="d" d:DesignWidth="800" d:DesignHeight="450"
			 x:DataType="vm:MainWindowViewModel"
             x:Class="AvaloniaApplicationBase.Views.AddCatPage">
	<Grid>
		<StackPanel>
			<TextBlock>Введите имя кота</TextBlock>
			<TextBox Text="{Binding AddCatVM.Name}"></TextBox>
			<TextBlock>Выберите дату рождения</TextBlock>
			<DatePicker SelectedDate="{Binding AddCatVM.Date}"></DatePicker>
			<TextBlock>Выберите пол</TextBlock>
			<ComboBox SelectedIndex="{Binding AddCatVM.Gender}">
				<ComboBoxItem>Мужской</ComboBoxItem>
				<ComboBoxItem>Женский</ComboBoxItem>
			</ComboBox>
			<TextBlock>Выберите черты характера кота</TextBlock>
			<ListBox ItemsSource="{Binding AddCatVM.SelectedTraits}"></ListBox>
			<ComboBox ItemsSource="{Binding AddCatVM.NewTraits}" SelectedValue="{Binding AddCatVM.SelectedTraitCat}"></ComboBox>
			<Button Command="{Binding AddCatVM.addNewCat}">Добавить кота</Button>
		</StackPanel>
	</Grid>
</UserControl>