Hi all,
I'd like to add my custom control into a template column of data grid.
The custom control is very similar to a text box, but has an icon in it. The user can click the icon, and selects an item from a prompted window, then the selected item will be filled into the text box.
My problem is when the text box is filled, after I click the second column, the text will disappear.  If I replace the custom control with a simple text box, the result is the same. 
Here is the sample code:
 //Employee.cs
    using System;
    using System.Collections.Generic;
    using System.Linq;
    using System.Text;
    namespace SimpleGridTest
    {
        public class Employee
        {
            public string Department { get; set; }
            public int ID { get; set; }
            public string Name { get; set; }
        }
    }
Mainwindow.xaml
<Window x:Class="SimpleGridTest.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        Title="MainWindow" Height="350" Width="525">
    <Grid>
        <DataGrid x:Name="grid" Grid.Row="1" Margin="5" AutoGenerateColumns="False"
                  RowHeight="25" RowHeaderWidth="10" 
                  ItemsSource="{Binding}"
                  CanUserAddRows="True" CanUserSortColumns="False">
            <DataGrid.Columns>
                <DataGridTemplateColumn Header="Department" Width="150">
                    <DataGridTemplateColumn.CellTemplate>
                        <DataTemplate>
                            <TextBox Text="{Binding Department}" />
                        </DataTemplate>
                    </DataGridTemplateColumn.CellTemplate>
                </DataGridTemplateColumn>
                <DataGridTextColumn Header="ID" Binding="{Binding Path=ID}"                                    
                                    Width="100"/>
                <DataGridTextColumn Header="Name" 
                                    Binding="{Binding Path=Name}"
                                    Width="200"/>
            </DataGrid.Columns>
        </DataGrid>
    </Grid>
</Window>
MainWindow.xaml.cs
using System.Windows;
using System.Collections.ObjectModel;
namespace SimpleGridTest
{
    /// <summary>
    /// Interaction logic for MainWindow.xaml
    /// </summary>
    public partial class MainWindow : Window
    {
        private ObservableCollection<Employee> _employees = new ObservableCollection<Employee>();
        public ObservableCollection<Employee> Employees
        {
            get { return _employees; }
            set { _employees = value; }
        }
        public MainWindow()
        {
            InitializeComponent();
            grid.ItemsSource = Employees;
        }
    }
}
How can I fix this problem? Or I need to write a DataGrid***Column as DataGridTextColumn? Thanks in advance!
Best Regards,
Johnson