3

我正在尝试使用 Castle Windsor Dynamic Proxies 实现 WPF ViewModel。这个想法是我想提供一个接口(下面的 IPerson 应该足以作为示例)、一个具体的支持类和一个拦截器(用于提供 INotifyPropertyChanged 的​​自动实现)。拦截器实现在这里:http ://www.hightech.ir/SeeSharp/Best-Implementation-Of-INotifyPropertyChange-Ever

我看到的问题是,当我将模型绑定到 WPF 控件时,控件不会将模型视为实现 INotifyPropertyChanged。我相信(但不确定)这是因为 Windsor 正在显式地实现接口,而 WPF 似乎期望它们是隐式的。

有什么办法可以使这项工作,以便模型的更改被拦截器捕获并提升到模型?

所有版本的库都是最新的:Castle.Core 2.5.1.0 和 Windsor 2.5.1.0

代码如下:

// My model's interface
public interface IPerson : INotifyPropertyChanged
{
    string First { get; set; }
    string LastName { get; set; }
    DateTime Birthdate { get; set; }
}

// My concrete class:
[Interceptor(typeof(NotifyPropertyChangedInterceptor))]
class Person : IPerson
{
    public event PropertyChangedEventHandler PropertyChanged = (s,e)=> { };
    public string First { get; set; }
    public string LastName { get; set; }
    public DateTime Birthdate { get; set; }
}

// My windsor installer
public class Installer : IWindsorInstaller
{
    public void Install(IWindsorContainer container, IConfigurationStore store)
    {
        container.Register(
            Component.For<NotifyPropertyChangedInterceptor>()
            .ImplementedBy<NotifyPropertyChangedInterceptor>()
            .LifeStyle.Transient);
        container.Register(
            Component.For<IPerson, INotifyPropertyChanged>()
            .ImplementedBy<Person>().LifeStyle.Transient);
    }
}
4

2 回答 2

4

所以答案变得相当简单......来自http://www.hightech.ir/SeeSharp/Best-Implementation-Of-INotifyPropertyChange-Ever的代码将拦截器定义为:

public class NotifyPropertyChangedInterceptor : IInterceptor
{
    private PropertyChangedEventHandler _subscribers = delegate { };

    public void Intercept(IInvocation invocation)
    {
        if (invocation.Method.DeclaringType == typeof(INotifyPropertyChanged))
        {
            HandleSubscription(invocation);
            return;
        }

        invocation.Proceed();

        if (invocation.Method.Name.StartsWith("set_"))
        {
            FireNotificationChanged(invocation);
        }
    }

    private void HandleSubscription(IInvocation invocation)
    {
        var handler = (PropertyChangedEventHandler)invocation.Arguments[0];

        if (invocation.Method.Name.StartsWith("add_"))
        {
            _subscribers += handler;
        }
        else
        {
            _subscribers -= handler;
        }
    }

    private void FireNotificationChanged(IInvocation invocation)
    {
        var propertyName = invocation.Method.Name.Substring(4);
        _subscribers(invocation.InvocationTarget, new PropertyChangedEventArgs(propertyName));
    }
}

就我而言, InvocationTarget 根本不是作为第一个参数传递给 PropertyChanged 的​​正确实体(因为我正在生成代理)。将最后一个函数更改为以下函数可以解决问题:

private void FireNotificationChanged(IInvocation invocation)
{
    var propertyName = invocation.Method.Name.Substring(4);
    _subscribers(invocation.Proxy, new PropertyChangedEventArgs(propertyName));
}
于 2011-05-09T14:54:04.153 回答
0

我认为您需要使实现接口虚拟的类的成员。

于 2011-05-07T04:37:35.477 回答