如何将样式设置器添加为静态资源的附加行为

Question

我使用附加的依赖项属性创建了一个行为，以将常见的 SetterBaseCollection 提供给不同的相关样式。

该行为只是管理附加主机上的集合属性以使其与视图中的静态资源对齐。我只是将其连接到 AP PropertyChangedCallback，这对于我拥有的另一种行为来说效果很好，即填充 CommandBindings，但是当我将其应用于样式设置器时抛出。

错误是

System.Windows.Markup.XamlParseException occurred
  _HResult=-2146233087
  _message='Set property 'System.Windows.EventSetter.Event' threw an exception.' Line number '12' and line position '26'.
  HResult=-2146233087
  IsTransient=false
  Message='Set property 'System.Windows.EventSetter.Event' threw an exception.' Line number '12' and line position '26'.
  Source=PresentationFramework
  LineNumber=12
  LinePosition=26
  StackTrace:
       at System.Windows.Markup.XamlReader.RewrapException(Exception e, IXamlLineInfo lineInfo, Uri baseUri)
  InnerException: System.ArgumentNullException
       _HResult=-2147467261
       _message=Value cannot be null.
       HResult=-2147467261
       IsTransient=false
       Message=Value cannot be null.
Parameter name: value
       Source=PresentationFramework
       ParamName=value
       StackTrace:
            at System.Windows.EventSetter.set_Event(RoutedEvent value)
       InnerException:

在错误发生之前不会调用行为代码，因此它在 xaml.

中

风景

<Window.Resources>

    <Thickness x:Key="ButtonMargin">6</Thickness>

    <SetterBaseCollection x:Key="ButtonStyleSetters">
        <EventSetter Event="ButtonBase.Click" Handler="StyleClick" />
        <Setter Property="FrameworkElement.Height" Value="30" />
        <Setter Property="FrameworkElement.Margin" Value="6" />
    </SetterBaseCollection>

    <Style TargetType="{x:Type Button}" 
           b:Behaviours.StyleSetters="{StaticResource ButtonStyleSetters}" />
    <Style TargetType="{x:Type ToggleButton}"
           b:Behaviours.StyleSetters="{StaticResource ButtonStyleSetters}" />
    <Style TargetType="{x:Type CheckBox}">
        <EventSetter Event="Click" Handler="StyleClick" />
    </Style>
    <Style TargetType="{x:Type b:MultiCommandButton}"
           b:Behaviours.StyleSetters="{StaticResource ButtonStyleSetters}" />

    <Style TargetType="UniformGrid">
        <Setter Property="Columns" Value="2" />
    </Style>

    <CommandBindingCollection x:Key="OutputToggleReceiveAll">
        <b:OutputToggleBind />
        <b:OutputToggleEnabledBind />
    </CommandBindingCollection>

</Window.Resources>

行为

public static class Behaviours
{
    #region AP CommandReceivers

    public static readonly DependencyProperty CommandReceiversProperty =
        DependencyProperty.RegisterAttached(
            "CommandReceivers", typeof(CommandBindingCollection),
            typeof(Behaviours),
            new PropertyMetadata(default(CommandBindingCollection),
                (t, a) => UpdateCollection<CommandBindingCollection, UIElement>
                    (t, a, "CommandBindings")));

    public static void SetCommandReceivers(DependencyObject element,
        CommandBindingCollection value)
    {
        element.SetValue(CommandReceiversProperty, value);
    }

    public static CommandBindingCollection GetCommandReceivers(
        DependencyObject element)
    {
        return (CommandBindingCollection) element
            .GetValue(CommandReceiversProperty);
    }

    #endregion

    #region AP StyleSetters

    public static readonly DependencyProperty StyleSettersProperty =
        DependencyProperty.RegisterAttached(
            "StyleSetters", typeof(SetterBaseCollection),
            typeof(Behaviours),
            new PropertyMetadata(default(SetterBaseCollection),
                (t, a) => UpdateCollection<SetterBaseCollection, UIElement>
                    (t, a, "Setters")));

    public static void SetStyleSetters (DependencyObject element,
        SetterBaseCollection value)
    {
        element.SetValue(StyleSettersProperty, value);
    }

    public static SetterBaseCollection GetStyleSetters (
        DependencyObject element)
    {
        return (SetterBaseCollection)element
            .GetValue(StyleSettersProperty);
    }

    #endregion

    private static void UpdateCollection<TCollection, THost> (
        DependencyObject target, DependencyPropertyChangedEventArgs args, 
        string targetCollection)
        where TCollection : IList
        where THost : class
    {
        var host = target as THost;
        if (host == null) return;

        var collection = typeof(THost).GetProperty(targetCollection)
            .GetValue(host) as IList;
        if (collection == null) return;

        if (args.OldValue != null)
        {
            foreach (var member in
                (TCollection) args.OldValue)
            {
                collection.Remove(member);
            }
        }
        if (args.NewValue != null)
        {
            foreach (var member in
                (TCollection) args.NewValue)
            {
                collection.Add(member);
            }
        }
    }
}

问题

我想我可能还必须添加一个 OnAttached 处理程序，但是我在 xaml 中做错了什么吗？令人讨厌的是找不到附加的属性但这通常不是问题，我希望它会在程序集成功编译后消失。

编辑

根据@mm8 和 this answer 的反馈，我尝试了以下方法，但也抛出错误。

查看

<Window.Resources>

    <SetterBaseCollection x:Key="ButtonStyleSetters">
        <EventSetter Event="ButtonBase.Click" Handler="StyleClick" />
        <Setter Property="FrameworkElement.Height" Value="30" />
        <Setter Property="FrameworkElement.Margin" Value="6" />
    </SetterBaseCollection>

    <Style TargetType="{x:Type Button}" >
        <Setter Property="local:Behaviours.StyleSetters" 
                Value="{StaticResource ButtonStyleSetters}"/>
    </Style>

</Window.Resources>

在行为中class

public static readonly DependencyProperty StyleSettersProperty =
    DependencyProperty.RegisterAttached(
        "StyleSetters", typeof(SetterBaseCollection),
        typeof(Behaviours),
        new PropertyMetadata(default(SetterBaseCollection),
            (t, a) => UpdateCollection<SetterBaseCollection, Style>
                (((FrameworkElement)t).Style, a, "Setters")));

public static void SetStyleSetters (DependencyObject element,
    SetterBaseCollection value)
{
    element.SetValue(StyleSettersProperty, value);
}

public static SetterBaseCollection GetStyleSetters (
    DependencyObject element)
{
    return (SetterBaseCollection)element
        .GetValue(StyleSettersProperty);
}

#endregion

private static void UpdateCollection<TCollection, THost> (
    object target, DependencyPropertyChangedEventArgs args, 
    string targetCollection)
    where TCollection : class, IList
    where THost : class
{
    var host = target as THost;
    if (host == null) return;

    var collection = typeof(THost).GetProperty(targetCollection)
        .GetValue(host) as IList;
    if (collection == null) return;

    var oldValue = args.OldValue as TCollection;
    if (oldValue != null)
    {
        foreach (var member in oldValue)
        {
            collection.Remove(member);
        }
    }
    try
    {
        var newValue = args.NewValue as TCollection;
        if (newValue != null)
        {
            foreach (var member in newValue)
            {
                collection.Add(member);
            }
        }

    }
    catch (Exception e)
    {
        Debug.WriteLine("{0} in UpdateCollection<TCollection, THost>");
    }
}

StaticResource 的值始终为 null。
每次在按钮上设置属性并将按钮作为第一个参数传递时，都会触发 OnPropertyChanged 回调。

Answer 1

Style 不是 DependencyObject，因此您将无法在 Style 上设置附加属性的 StyleSetter。

如何将样式设置器添加为静态资源的附加行为

How to add style setters as an attached behaviour from a static resource

c#

wpf

attached-properties

visual-studio-2013

风景

行为

问题

编辑

查看

在行为中class