与自定义对象绑定时的依赖属性神经元设置

Question

我正在尝试通过依赖项属性将传递的类型为“ CommandButton_VModel”的自定义对象绑定到User控件，但是似乎从未击中该dp的安装程序。我的意思是，在用户控件中，依赖项属性始终为null，有人可以告诉我我失败了吗？

下面是我的代码：

UserControl XAML：

<UserControl x:Class="FireAntTempConfigurer.UserControls.CommandButton_UC"
             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" 
             xmlns:local="clr-namespace:FireAntTempConfigurer.UserControls"
             xmlns:materialDesign="clr-namespace:MaterialDesignThemes.Wpf;assembly=MaterialDesignThemes.Wpf"
             mc:Ignorable="d" 
             TextElement.Foreground="{DynamicResource MaterialDesignPaper}"
             d:DesignHeight="60 " d:DesignWidth="60">
    <Grid>
        <Button Height="50" Padding="0,0,0,0" Margin="5" ToolTip="{Binding PlaceHolder}">
            <Button.Content>
                <materialDesign:PackIcon Kind="{Binding Icon}" Height="50" Width="50" />
            </Button.Content>
        </Button>
    </Grid>
</UserControl>

后面的用户控制代码

    public partial class CommandButton_UC : UserControl
    {

        public CommandButton_UC()
        {
            DataContext = CmdBtn;
            InitializeComponent();
        }

        public CommandButton_VModel CmdBtn
        {
            get { return (CommandButton_VModel)GetValue(CmdBtnProperty); }
            set { SetValue(CmdBtnProperty, value); }
        }

        public static readonly DependencyProperty CmdBtnProperty =
            DependencyProperty.Register("CmdBtn", typeof(CommandButton_VModel), typeof(CommandButton_UC), new PropertyMetadata(default(CommandButton_VModel)));
    }

MainWindow XAML：

            <StackPanel>
                <TextBlock>ToolBox:</TextBlock>
                <Separator></Separator>
                <StackPanel Orientation="Horizontal">
                    <cmdBtn:CommandButton_UC CmdBtn="{Binding MyProperty ,Mode=OneWayToSource}">
                    </cmdBtn:CommandButton_UC>
                </StackPanel>
            </StackPanel>

MainWindow代码

    public partial class MainWindow : Window
    {

        public CommandButton_VModel MyProperty { get; set; }

        public MainWindow()
        {
            MyProperty = new CommandButton_VModel { Icon = "Plus", PlaceHolder = "Add" };
            DataContext = MyProperty;
            InitializeComponent();
        }


    }

ViewModel

    public class CommandButton_VModel : INotifyPropertyChanged
    {
        public string Icon { get; set; }
        public string PlaceHolder { get; set; }

        public event PropertyChangedEventHandler PropertyChanged;

        public CommandButton_VModel()
        {
            if (PropertyChanged != null)
            {
                PropertyChanged(this, new PropertyChangedEventArgs("Icon"));
                PropertyChanged(this, new PropertyChangedEventArgs("PlaceHolder"));
            }
        }
    }

谢谢！