如果没有具体看到您正在努力解决的问题,很难说,但这也许有帮助?
编辑
由于分配的正确答案中的指针,我(bradgonesurfing)提出的解决方案如下。
节点
和实现代码。它依赖于 ReactiveUI 和私有库中的辅助函数,用于将 ISubject 绑定到 INPC 支持对象上的可变属性
using ReactiveUI.Subjects;
using System;
using System.Linq;
using System.Reactive.Subjects;
using System.Windows;
using System.Windows.Data;
using System.Windows.Markup;
namespace ReactiveUI.Markup
{
[MarkupExtensionReturnType(typeof(BindingExpression))]
public class SubscriptionExtension : MarkupExtension
{
[ConstructorArgument("path")]
public PropertyPath Path { get; set; }
public SubscriptionExtension() { }
public SubscriptionExtension(PropertyPath path)
{
Path = path;
}
class Proxy : ReactiveObject
{
string _Value;
public string Value
{
get { return _Value; }
set { this.RaiseAndSetIfChanged(value); }
}
}
public override object ProvideValue(IServiceProvider serviceProvider)
{
var pvt = serviceProvider as IProvideValueTarget;
if (pvt == null)
{
return null;
}
var frameworkElement = pvt.TargetObject as FrameworkElement;
if (frameworkElement == null)
{
return this;
}
object propValue = GetProperty(frameworkElement.DataContext, Path.Path);
var subject = propValue as ISubject<string>;
var proxy = new Proxy();
Binding binding = new Binding()
{
Source = proxy,
Path = new System.Windows.PropertyPath("Value")
};
// Bind the subject to the property via a helper ( in private library )
var subscription = subject.ToMutableProperty(proxy, x => x.Value);
// Make sure we don't leak subscriptions
frameworkElement.Unloaded += (e,v) => subscription.Dispose();
return binding.ProvideValue(serviceProvider);
}
private static object GetProperty(object context, string propPath)
{
object propValue = propPath
.Split('.')
.Aggregate(context, (value, name)
=> value.GetType()
.GetProperty(name)
.GetValue(value, null));
return propValue;
}
}
}