test/FirstSlice/MainWindow.axaml

<Window 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"
        x:Class="FirstSlice.MainWindow"
        WindowStartupLocation="CenterScreen"
        Title="FirstSlice">
        
        <TabControl>
                <TabItem Header="Пользователи">
                        <Grid>
                                <Grid.RowDefinitions>
                                        <RowDefinition></RowDefinition>
                                        <RowDefinition Height="5*"></RowDefinition>
                                </Grid.RowDefinitions>
                                
                                <StackPanel Orientation="Horizontal">
                                        <Button Name="AddUser" Click="OnAddUserClick" Content="Добавить пользователя" VerticalAlignment="Center" Margin="10"></Button>
                                        <Button Name="DeleteUser" Click="OnDeleteUserClick" Content="Удалить пользователя" VerticalAlignment="Center" Margin="10"></Button>
                                </StackPanel>
                                
                                <DataGrid Grid.Row="1" Name="UserTable" DoubleTapped="OnUserTableDoubleTapped">
                                        <DataGrid.Columns>
                                                <DataGridTextColumn Header="ФИО" Binding="{Binding Fullname}"/>
                                                <DataGridTextColumn Header="Дата рождения" Binding="{Binding Birthday}"/>
                                                <DataGridTextColumn Header="Номер телефона" Binding="{Binding Phonenumber}"/>
                                                <DataGridTextColumn Header="Адрес" Binding="{Binding Address}"/>
                                                <DataGridTextColumn Header="Роль" Binding="{Binding FkRole.Name}"/>
                                        </DataGrid.Columns>
                                </DataGrid>
                        </Grid>
                </TabItem>
                
                
                <TabItem Header="Роль">
                        <Grid>
                                <Grid.RowDefinitions>
                                        <RowDefinition></RowDefinition>
                                        <RowDefinition Height="5*"></RowDefinition>
                                </Grid.RowDefinitions>
                                
                                <StackPanel Orientation="Horizontal">
                                        <Button Name="AddRole" Content="Добавить роль" Click="OnAddRoleClick" VerticalAlignment="Center" Margin="10"></Button>
                                        <Button Name="DeleteRole" Content="Удалить роль" Click="OnDeleteRoleClick" VerticalAlignment="Center" Margin="10"></Button>
                                </StackPanel>
                                
                                <DataGrid Grid.Row="1" Name="RoleTable" DoubleTapped="OnRoleTableDoubleTapped">
                                        <DataGrid.Columns>
                                                <DataGridTextColumn Header="Роль" Binding="{Binding Name}"/>
                                        </DataGrid.Columns>
                                </DataGrid>
                        </Grid>
                </TabItem>
        </TabControl>
        
</Window>