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我有一个multibinding看起来是这样的：WPF - 延迟Multibinding
<UserControl.Visibility>
<MultiBinding Converter="{StaticResource isMouseOverToVisibiltyConverter}">
<Binding ElementName="otherElement" Path="IsMouseOver" />
<Binding RelativeSource="{RelativeSource Self}" Path="IsMouseOver" />
</MultiBinding>
</UserControl.Visibility>
而且，我希望能够IsMouseOver去假两个绑定之间添加延迟，能见度被设置为崩溃了。
我发现这个DelayBinding实现： http://www.paulstovell.com/wpf-delaybinding
但是，这并不对MultiBinding工作，我一直无法弄清楚如何使一个与MultiBinding工作。
我确实可以选择在代码隐藏的事件中对可见性进行更改，这样做会起作用，但如果有某种方法可以通过绑定系统执行此操作，那将会很不错。
有没有办法给MultiBinding添加延迟？
编辑：雷，为了让你的类编译&运行，我不得不做一些修复。但是，有些东西仍然是错误的，因为更新没有被传播。它似乎只更新一次目标属性。
[ContentProperty("Bindings")]
public class DelayedMultiBindingExtension : MarkupExtension, IMultiValueConverter, INotifyPropertyChanged
{
public Collection<BindingBase> Bindings { get; private set; }
public IMultiValueConverter Converter { get; set; }
public object ConverterParameter { get; set; }
public CultureInfo ConverterCulture { get; set; }
public BindingMode Mode { get; set; }
public UpdateSourceTrigger UpdateSourceTrigger { get; set; }
public object CurrentValue { get { return _delayedValue; } set { _delayedValue = _undelayedValue = value; _timer.Stop(); } }
private object _undelayedValue;
private object _delayedValue;
private DispatcherTimer _timer;
public int ChangeCount { get; private set; } // Public so Binding can bind to it
public DelayedMultiBindingExtension()
{
this.Bindings = new Collection<BindingBase>();
_timer = new DispatcherTimer();
_timer.Tick += _timer_Tick;
_timer.Interval = TimeSpan.FromMilliseconds(500);
}
public override object ProvideValue(IServiceProvider serviceProvider)
{
var valueProvider = serviceProvider.GetService(typeof(IProvideValueTarget)) as IProvideValueTarget;
if (valueProvider != null)
{
var bindingTarget = valueProvider.TargetObject as DependencyObject;
var bindingProperty = valueProvider.TargetProperty as DependencyProperty;
var multi = new MultiBinding { Converter = this, Mode = Mode, UpdateSourceTrigger = UpdateSourceTrigger };
foreach (var binding in Bindings)
multi.Bindings.Add(binding);
multi.Bindings.Add(new Binding("ChangeCount") { Source = this, Mode = BindingMode.OneWay });
var bindingExpression = BindingOperations.SetBinding(bindingTarget, bindingProperty, multi);
return bindingTarget.GetValue(bindingProperty);
}
return null;
}
public object Convert(object[] values, Type targetType, object parameter, CultureInfo culture)
{
object newValue =
Converter.Convert(
values.Take(values.Length - 1).ToArray(),
targetType,
ConverterParameter,
ConverterCulture ?? culture);
if (!object.Equals(newValue, _undelayedValue))
{
_undelayedValue = newValue;
_timer.Stop();
_timer.Start();
}
return _delayedValue;
}
public object[] ConvertBack(object value, Type[] targetTypes, object parameter, CultureInfo culture)
{
return
Converter.ConvertBack(value, targetTypes, ConverterParameter, ConverterCulture ?? culture)
.Concat(new object[] { ChangeCount }).ToArray();
}
private void _timer_Tick(object sender, EventArgs e)
{
_timer.Stop();
_delayedValue = _undelayedValue;
ChangeCount++;
if (PropertyChanged != null)
PropertyChanged(this, new PropertyChangedEventArgs("ChangeCount"));
}
public event PropertyChangedEventHandler PropertyChanged;
}
EDIT2：虽然我不能让雷的代码工作中，我将其标记为答案，因为它导致了我的一些代码，做的工作。查看我的答案，下面是我使用的代码。
这个问题帮助我解决了我的问题，非常感谢！ – worldpart 2017-10-17 20:30:59