自定义控件中的数据网格未更新

在我的自定义控件中，它有一个 DataGrid 和两个按钮，一个用于在此 DataGrid 中添加行，另一个用于删除元素的按钮。

（由于我的声誉，我不能在这里发布图片，对不起！ ：-（

我的自定义控件代码隐藏：

    /// <summary>
    /// Interaction logic for UserControl1.xaml
    /// </summary>
    public partial class CustonDatagrid : UserControl
    {
        public CustonDatagrid()
        {
            InitializeComponent();
        }
        #region DependencyProperty Content
        /// <summary>
        /// Registers a dependency property as backing store for the Content property
        /// </summary>
        public static readonly DependencyProperty ColectionProperty =
            DependencyProperty.Register("Colection",
            typeof(ObservableCollection<object>),
            typeof(CustonDatagrid),
            new FrameworkPropertyMetadata(null,
                  FrameworkPropertyMetadataOptions.AffectsRender |
                  FrameworkPropertyMetadataOptions.AffectsParentMeasure));
        /// <summary>
        /// Gets or sets the Content.
        /// </summary>
        /// <value>The Content.</value>
        public ObservableCollection<object> Colection
        {
            get { return (ObservableCollection<object>)GetValue(ColectionProperty); }
            set { SetValue(ColectionProperty, value); }
        }
        #endregion
        public static readonly RoutedEvent AddButtonEvent = EventManager.RegisterRoutedEvent(
            "AddButtonClick",
            RoutingStrategy.Bubble, 
            typeof (RoutedEventHandler),
            typeof (CustonDatagrid));
        public event RoutedEventHandler AddButtonClick
        {
            add { AddHandler(AddButtonEvent, value); }
            remove { RemoveHandler(AddButtonEvent, value);}
        }
        private void ButtonBase_OnClick(object sender, RoutedEventArgs e)
        {
            var newEventArgs = new RoutedEventArgs(AddButtonEvent);
            RaiseEvent(newEventArgs);
        }
    }

我的 .xaml：

    <UserControl x:Class="WpfCustomControlLibrary1.CustonDatagrid"
             xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
             xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" 
             xmlns:d="http://schemas.microsoft.com/expression/blend/2008" 
             mc:Ignorable="d" 
             d:DesignHeight="300" d:DesignWidth="300" Name="CustonDataGrid">
    <Grid>
            <DockPanel LastChildFill="True" >
                <StackPanel DockPanel.Dock="Bottom" HorizontalAlignment="Right" Orientation="Horizontal">
                    <Button Margin="5" Width="20" Click="ButtonBase_OnClick" >+</Button>
                <Button Margin="5" Width="20">-</Button>
            </StackPanel>
                <DataGrid ItemsSource="{Binding ElementName=CustonDataGrid, Path=Colection}" DockPanel.Dock="Top"></DataGrid>
            </DockPanel>
    </Grid>
</UserControl>

以及 wpf 窗口中的用法：

XAML 代码：

    <Window x:Class="WpfApplication1.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:wpfCustomControlLibrary1="clr-namespace:WpfCustomControlLibrary1;assembly=WpfCustomControlLibrary1"
        Title="MainWindow" Height="350" Width="525"
        DataContext="{Binding RelativeSource={RelativeSource Self}, Path=Model}"
        >
    <Grid>
        <wpfCustomControlLibrary1:CustonDatagrid Colection="{Binding Path=Colection}" AddButtonClick="CustonDatagrid_OnAddButtonClick">
        </wpfCustomControlLibrary1:CustonDatagrid>
    </Grid>
</Window>

而背后的代码+视图模型+数据网格行视图模型：

/// <summary>
/// Interaction logic for MainWindow.xaml
/// </summary>
public partial class MainWindow : Window
{
    public MainWindow()
    {
        Model = new Model();
        InitializeComponent();
    }
    public Model Model { get; set; }
    private void CustonDatagrid_OnAddButtonClick(object sender, RoutedEventArgs e)
    {
        Model.AddElement();
    }
}
public class Model : INotifyPropertyChanged
{
    public ObservableCollection<DataGridRowModel> Colection { get; set; }
    public void AddElement()
    {
        if (Colection == null) Colection = new ObservableCollection<DataGridRowModel>();
        Colection.Add( new DataGridRowModel()
        {
            Name = "Test"
        });
    }
    public event PropertyChangedEventHandler PropertyChanged;
    [NotifyPropertyChangedInvocator]
    protected virtual void OnPropertyChanged([CallerMemberName] string propertyName = null)
    {
        var handler = PropertyChanged;
        if (handler != null) handler(this, new PropertyChangedEventArgs(propertyName));
    }
}
public class DataGridRowModel
{
    public string Name { get; set; }
}

我遇到的问题是数据网格没有显示添加到集合中的新元素。调试时，我可以看到我的集合包含许多元素（每次单击 （+） 按钮时一个），但这些元素不会显示在视图中。

有人可以给我一个提示，我犯了错误或（可能）丢失了代码吗?!?

谢谢。

<DataGrid ItemsSource="{Binding ElementName=CustonDataGrid, Path=Colection}" DockPanel.Dock="Top"></DataGrid>

<DataGrid ItemsSource="{Binding Path=Colection}"></DataGrid>

public partial class MainWindow : Window
{
    public MainWindow()
    {
        Model = new Model();
        InitializeComponent();
        this.DataContext = Model;
    }
    public Model Model { get; set; }
    private void CustonDatagrid_OnAddButtonClick(object sender, RoutedEventArgs e)
    {
        Model.AddElement();
    }
}

<Window x:Class="WpfApplication1.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:wpfCustomControlLibrary1="clr-namespace:WpfCustomControlLibrary1;assembly=WpfCustomControlLibrary1"
        Title="MainWindow" Height="350" Width="525">
    <ScrollViewer>
        <wpfCustomControlLibrary1:CustonDatagrid Colection="{Binding Colection,Mode=TwoWay}" AddButtonClick="CustonDatagrid_OnAddButtonClick">
        </wpfCustomControlLibrary1:CustonDatagrid>
    </ScrollViewer>
</Window>

public class Model : INotifyPropertyChanged
{
    public ObservableCollection<DataGridRowModel> Colection { get; set; }
    public Model()
    {
        Colection = new ObservableCollection<DataGridRowModel>();
    }
    public void AddElement()
    {
        Colection.Add(new DataGridRowModel { Name = "Test" });
    }
    public event PropertyChangedEventHandler PropertyChanged;
    protected virtual void OnPropertyChanged(string propertyName)
    {
        var handler = PropertyChanged;
        if (handler != null)
            handler(this, new PropertyChangedEventArgs(propertyName));
    }
}