WPF自定义控件:DependencyProperty从不设置(仅在许多属性中的1个)

Question

我创建了一个名为AddressForm的自定义控件,它继承自Control.该控件用于显示IAddress对象的字段.

最初我在Silverlight中制作了这个控件,现在我试图让它在WPF .net 4.5中运行

该控件定义了9个不同的依赖属性,除了一个外,所有属性都正常工作.当然,不工作的是Address对象本身!

Control的Address属性永远不会收到值.我在地址的Getter中放了一个断点,该属性被调用,地址对象不为null,但控件没有收到它.

输出屏幕中没有异常,也没有错误消息.

控制 :

public class AddressForm : Control, INotifyPropertyChanged
{
    [...]

    public static readonly DependencyProperty AddressProperty = DependencyProperty.Register("Address", typeof(IAddress), typeof(AddressForm), new PropertyMetadata( AddressChanged));
    public IAddress Address 
    {
        get { return (IAddress)GetValue(AddressProperty); }
        set { SetValue(AddressProperty, value); } 
    }

    private static void AddressChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
    {
        //break-point here never gets hit
        AddressForm form = d as AddressForm;
        if (form != null)
            form.OnAddressSet();
    }

    private void OnAddressSet()
    {
        //break-point here never gets hit
        if (StateProvince != null && Address != null)
        SelectedStateProvince = StateProvince.Where(A => A.StateProvince == Address.StateProvince).FirstOrDefault();
    }

    [...]
}

(其他DependencyProperties以相同的方式设置并正常工作.)

xaml:

<Address:AddressForm Address="{Binding SelectedMFG.dms_Address, Mode=TwoWay}" ... />

SelectedMFG的类型是scm_MFG

数据对象:

public partial class scm_MFG 
{
    [...]
    public virtual dms_Address dms_Address { get; set; } //break-point here never enables? Generated code from Entity TT

    //Another attempt, trying to determine if the IAddress cast was the cause of the issue
    //Address="{Binding SelectedMFG.OtherAddress}" 
    public IAddress OtherAddress 
    {
        get { 
            return dms_Address as IAddress; //break-point here gets hit. dms_Address is not null. Control never receives the value.
        } 
    }
}

public partial class dms_Address : IAddress, INotifyPropertyChanged { ... }

我的尝试:

我试过以不同的方式访问dms_Address属性.我可以在文本框中显示地址的值,这告诉我datacontext没有问题.

<TextBox  Text="{Binding SelectedMFG.dms_Address.StreetName, Mode=TwoWay}" /> <!-- this value displays -->

我也尝试更改依赖属性的注册元数据.我不确定哪个是正确的:PropertyMetadata,UIPropertyMetadata或FrameworkPropertyMetadata

DependencyProperty.Register("Address", typeof(IAddress), typeof(AddressForm), new PropertyMetadata(AddressChanged));
DependencyProperty.Register("Address", typeof(IAddress), typeof(AddressForm), new PropertyMetadata(null, AddressChanged));
DependencyProperty.Register("Address", typeof(IAddress), typeof(AddressForm), new UIPropertyMetadata(AddressChanged));
DependencyProperty.Register("Address", typeof(IAddress), typeof(AddressForm), new FrameworkPropertyMetadata(null, FrameworkPropertyMetadataOptions.Inherits, AddressChanged));
// and other FrameworkPropertyMetadataOptions, no difference

.

我相信我已经做了一切正确的事情,这应该是有效的.

有什么事情是奇怪的或不正确的吗？

Answer 1

我找到了解决方案。

我将表单上的地址依赖属性从IAddress更改为Object。现在房产正在准备中。看起来，即使我返回IAddress对象，表单实际接收的对象也是dms_Address 的EntityWrapper。

这个实体包装器也会转换为IAddress，所以我不确定它为什么会这样。我猜这只是另一个实体的陷阱。