我想在DataGrid中的DataGridTemplateColumn内显示ComboBox中的数据，但它在绑定中为空，因此我决定在代码后面填充它，但我无法通过名称访问它！

XAML：

<Window x:Class="ComboDataWPF.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        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"
        xmlns:local="clr-namespace:ComboDataWPF"
        mc:Ignorable="d"
        Title="MainWindow" Height="450" Width="800" WindowStartupLocation="CenterScreen" Loaded="Window_Loaded">
    
    <Grid>
        <DataGrid x:Name="MainDataGrid" AutoGenerateColumns="False" ItemsSource="{Binding ALLMYDATA, UpdateSourceTrigger=PropertyChanged,Mode=TwoWay}">

            <DataGrid.Columns>
                <DataGridTextColumn Header="The Name :" Width="120" Binding="{Binding NAMES, UpdateSourceTrigger=PropertyChanged,Mode=TwoWay}" />

                <DataGridTemplateColumn Header=" Name and Code " Width="150">
                    <DataGridTemplateColumn.CellTemplate>
                        <DataTemplate>
                            <ComboBox x:Name="ComboBox1"
                                      ItemsSource="{Binding ALLMYDATA, UpdateSourceTrigger=PropertyChanged,Mode=TwoWay}"
                                      SelectedValuePath="{Binding CODE, UpdateSourceTrigger=PropertyChanged,Mode=TwoWay}"
                                      DisplayMemberPath="{Binding NAMES, UpdateSourceTrigger=PropertyChanged,Mode=TwoWay}"
                                      IsTextSearchEnabled="True"
                                      IsEditable="True"
                                      SelectedIndex="0"  BorderBrush="#FFADEEB4" Background="{x:Null}" BorderThickness="1">
                                
                                <ComboBox.ItemsPanel>
                                    <ItemsPanelTemplate>
                                        <VirtualizingStackPanel VirtualizingPanel.IsVirtualizing="True" VirtualizingPanel.VirtualizationMode="Recycling"/>
                                    </ItemsPanelTemplate>
                                </ComboBox.ItemsPanel>
                            </ComboBox>
                        </DataTemplate>
                    </DataGridTemplateColumn.CellTemplate>
                </DataGridTemplateColumn>
            </DataGrid.Columns>

        </DataGrid>
    </Grid>
</Window>

代码隐藏：

using System;
    using System.Collections.Generic;
    using System.Collections.ObjectModel;
    using System.ComponentModel;
    using System.Linq;
    using System.Text;
    using System.Threading.Tasks;
    using System.Windows;
    using System.Windows.Controls;
    using System.Windows.Data;
    using System.Windows.Documents;
    using System.Windows.Input;
    using System.Windows.Media;
    using System.Windows.Media.Imaging;
    using System.Windows.Navigation;
    using System.Windows.Shapes;
    
    namespace ComboDataWPF
    {
        /// <summary>
        /// Interaction logic for MainWindow.xaml
        /// </summary>
        public partial class MainWindow : Window
        {
            MyerEntities dbms = new MyerEntities();
            public ObservableCollection<MyCustomModel> ALLMYDATA { get; set; } = new ObservableCollection<MyCustomModel>();
            public class MyCustomModel
            {
                public int CODE { get; set; }
                public string NAMES { get; set; }
            }
            public MainWindow()
            {
                InitializeComponent();
                DataContext = this;
            }
            private void Window_Loaded(object sender, RoutedEventArgs e)
            {
                ALLMYDATA.Clear();
                var RST = dbms.Database.SqlQuery<MyCustomModel>("SELECT CODE,NAMES FROM TCOD_ANBAR").ToList();
                foreach (var item in RST)
                {
                    ALLMYDATA.Add(item);
                }
            }
        }
    }

我的源代码：https://ufile.io/zvfoj4we
注意：我甚至试图切换到GridView，但它比Datagrid更难。
那么为什么ComboBox是空的，我如何访问C#中的ItemsSource和...之类的属性？
请指引我