blocks|key|339827|text|尽管我非常喜欢XAML，但对于这类任务，我会改用后台代码。Attached+behaviors是一个很好的模式。请记住，Expression+Blend+3+provides+a+standard+way用于编程和使用行为。Expression社区站点上有a+few+existing+ones。|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|339828|entityMap|0|LINK|mutability|MUTABLE|url|http://www.codeproject.com/KB/WPF/AttachedBehaviors.aspx|1|http://sachabarber.net/?p=510|2|http://gallery.expression.microsoft.com/en-us/site/items/behaviors^0|T|I|0|27|N|1|3K|J|2|0^^$0|@$1|2|3|4|5|6|7|P|8|@]|9|@$A|Q|B|R|1|S]|$A|T|B|U|1|V]|$A|W|B|X|1|Y]]|C|$]]|$1|D|3|-4|5|6|7|Z|8|@]|9|@]|C|$]]]|E|$F|$5|G|H|I|C|$J|K]]|L|$5|G|H|I|C|$J|M]]|N|$5|G|H|I|C|$J|O]]]]

<p>As much as I love XAML, for this kinds of tasks I switch to code behind. <a href="http://www.codeproject.com/KB/WPF/AttachedBehaviors.aspx" rel="noreferrer">Attached behaviors</a> are a good pattern for this. Keep in mind, Expression Blend 3 <a href="http://sachabarber.net/?p=510" rel="noreferrer">provides a standard way</a> to program and use behaviors. There are <a href="http://gallery.expression.microsoft.com/en-us/site/items/behaviors" rel="noreferrer">a few existing ones</a> on the Expression Community Site.</p>


blocks|key|3322423|text|根据需要的来源，可以在代码后台或xaml中停止Storyboard。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|3322424|如果EventTrigger被移到按钮之外，那么我们可以继续并使用另一个EventTrigger来定位它，该and将告诉情节提要停止。当故事板以这种方式停止时，它将不会恢复到以前的值。|3322425|在这里，我将Button.Click+EventTrigger移到了周围的StackPanel中，并在EventTrigger上添加了一个新的CheckBox.Click，以便在单击CheckBox时停止按钮的故事板。这使我们可以在CheckBox被单击时选中和取消选中它，并为我们提供所需的按钮取消选中行为。|3322426|++++<StackPanel+x:Name="myStackPanel">

++++++++<CheckBox+x:Name="myCheckBox"
++++++++++++++++++Content="My+CheckBox"+/>

++++++++<Button+Content="Click+to+Uncheck"
++++++++++++++++x:Name="myUncheckButton"+/>

++++++++<Button+Content="Click+to+check+the+box+in+code."
++++++++++++++++Click="OnClick"+/>

++++++++<StackPanel.Triggers>

++++++++++++<EventTrigger+RoutedEvent="Button.Click"
++++++++++++++++++++++++++SourceName="myUncheckButton">
++++++++++++++++<EventTrigger.Actions>
++++++++++++++++++++<BeginStoryboard+x:Name="myBeginStoryboard">
++++++++++++++++++++++++<Storyboard+x:Name="myStoryboard">
++++++++++++++++++++++++++++<BooleanAnimationUsingKeyFrames+Storyboard.TargetName="myCheckBox"
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++Storyboard.TargetProperty="IsChecked">
++++++++++++++++++++++++++++++++<DiscreteBooleanKeyFrame+KeyTime="00:00:00"
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++Value="False"+/>
++++++++++++++++++++++++++++</BooleanAnimationUsingKeyFrames>
++++++++++++++++++++++++</Storyboard>
++++++++++++++++++++</BeginStoryboard>
++++++++++++++++</EventTrigger.Actions>
++++++++++++</EventTrigger>

++++++++++++<EventTrigger+RoutedEvent="CheckBox.Click"
++++++++++++++++++++++++++SourceName="myCheckBox">
++++++++++++++++<EventTrigger.Actions>
++++++++++++++++++++<StopStoryboard+BeginStoryboardName="myBeginStoryboard"+/>
++++++++++++++++</EventTrigger.Actions>
++++++++++++</EventTrigger>

++++++++</StackPanel.Triggers>
++++</StackPanel>|code-block|syntax|javascript|3322427|为了停止代码背后的故事板，我们必须做一些稍微不同的事情。第三个按钮提供了停止情节提要并通过代码将IsChecked属性设置回true的方法。|3322428|我们不能调用myStoryboard.Stop()，因为我们没有通过设置isControllable参数的代码开始故事板。相反，我们可以删除Storyboard。为此，我们需要故事板所在的FrameworkElement，在本例中是我们的StackPanel。一旦序列图像板被移除，我们可以再次设置IsChecked属性，使其持久化到UI中。|3322429|++++private+void+OnClick(object+sender,+RoutedEventArgs+e)
++++{
++++++++myStoryboard.Remove(myStackPanel);
++++++++myCheckBox.IsChecked+=+true;
++++}|3322430|entityMap^0|0|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|S|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|T|8|@]|9|@]|A|$]]|$1|D|3|E|5|6|7|U|8|@]|9|@]|A|$]]|$1|F|3|G|5|H|7|V|8|@]|9|@]|A|$I|J]]|$1|K|3|L|5|6|7|W|8|@]|9|@]|A|$]]|$1|M|3|N|5|6|7|X|8|@]|9|@]|A|$]]|$1|O|3|P|5|H|7|Y|8|@]|9|@]|A|$I|J]]|$1|Q|3|-4|5|6|7|Z|8|@]|9|@]|A|$]]]|R|$]]

<p>Stopping the Storyboard can be done in the code behind, or the xaml, depending on where the need comes from.</p>

<p>If the EventTrigger is moved outside of the button, then we can go ahead and target it with another EventTrigger that will tell the storyboard to stop.  When the storyboard is stopped in this manner it will not revert to the previous value.</p>

<p>Here I've moved the Button.Click EventTrigger to a surrounding StackPanel and added a new EventTrigger on the the CheckBox.Click to stop the Button's storyboard when the CheckBox is clicked.  This lets us check and uncheck the CheckBox when it is clicked on and gives us the desired unchecking behavior from the button as well.</p>

<pre><code>    &lt;StackPanel x:Name="myStackPanel"&gt;

        &lt;CheckBox x:Name="myCheckBox"
                  Content="My CheckBox" /&gt;

        &lt;Button Content="Click to Uncheck"
                x:Name="myUncheckButton" /&gt;

        &lt;Button Content="Click to check the box in code."
                Click="OnClick" /&gt;

        &lt;StackPanel.Triggers&gt;

            &lt;EventTrigger RoutedEvent="Button.Click"
                          SourceName="myUncheckButton"&gt;
                &lt;EventTrigger.Actions&gt;
                    &lt;BeginStoryboard x:Name="myBeginStoryboard"&gt;
                        &lt;Storyboard x:Name="myStoryboard"&gt;
                            &lt;BooleanAnimationUsingKeyFrames Storyboard.TargetName="myCheckBox"
                                                            Storyboard.TargetProperty="IsChecked"&gt;
                                &lt;DiscreteBooleanKeyFrame KeyTime="00:00:00"
                                                         Value="False" /&gt;
                            &lt;/BooleanAnimationUsingKeyFrames&gt;
                        &lt;/Storyboard&gt;
                    &lt;/BeginStoryboard&gt;
                &lt;/EventTrigger.Actions&gt;
            &lt;/EventTrigger&gt;

            &lt;EventTrigger RoutedEvent="CheckBox.Click"
                          SourceName="myCheckBox"&gt;
                &lt;EventTrigger.Actions&gt;
                    &lt;StopStoryboard BeginStoryboardName="myBeginStoryboard" /&gt;
                &lt;/EventTrigger.Actions&gt;
            &lt;/EventTrigger&gt;

        &lt;/StackPanel.Triggers&gt;
    &lt;/StackPanel&gt;
</code></pre>

<p>To stop the storyboard in the code behind, we will have to do something slightly different.  The third button provides the method where we will stop the storyboard and set the IsChecked property back to true through code.</p>

<p>We can't call myStoryboard.Stop() because we did not begin the Storyboard through the code setting the isControllable parameter.  Instead, we can remove the Storyboard.  To do this we need the FrameworkElement that the storyboard exists on, in this case our StackPanel.  Once the storyboard is removed, we can once again set the IsChecked property with it persisting to the UI.</p>

<pre><code>    private void OnClick(object sender, RoutedEventArgs e)
    {
        myStoryboard.Remove(myStackPanel);
        myCheckBox.IsChecked = true;
    }
</code></pre>


blocks|key|338547|text|只需创建自己的操作即可。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|338548|namespace+WpfUtil
{
++++using+System.Reflection;
++++using+System.Windows;
++++using+System.Windows.Interactivity;


++++///+<summary>
++++///+Sets+the+designated+property+to+the+supplied+value.+TargetObject
++++///+optionally+designates+the+object+on+which+to+set+the+property.+If
++++///+TargetObject+is+not+supplied+then+the+property+is+set+on+the+object
++++///+to+which+the+trigger+is+attached.
++++///+</summary>
++++public+class+SetPropertyAction+:+TriggerAction<FrameworkElement>
++++{
++++++++//+PropertyName+DependencyProperty.

++++++++///+<summary>
++++++++///+The+property+to+be+executed+in+response+to+the+trigger.
++++++++///+</summary>
++++++++public+string+PropertyName
++++++++{
++++++++++++get+{+return+(string)GetValue(PropertyNameProperty);+}
++++++++++++set+{+SetValue(PropertyNameProperty,+value);+}
++++++++}

++++++++public+static+readonly+DependencyProperty+PropertyNameProperty
++++++++++++=+DependencyProperty.Register("PropertyName",+typeof(string),
++++++++++++typeof(SetPropertyAction));


++++++++//+PropertyValue+DependencyProperty.

++++++++///+<summary>
++++++++///+The+value+to+set+the+property+to.
++++++++///+</summary>
++++++++public+object+PropertyValue
++++++++{
++++++++++++get+{+return+GetValue(PropertyValueProperty);+}
++++++++++++set+{+SetValue(PropertyValueProperty,+value);+}
++++++++}

++++++++public+static+readonly+DependencyProperty+PropertyValueProperty
++++++++++++=+DependencyProperty.Register("PropertyValue",+typeof(object),
++++++++++++typeof(SetPropertyAction));


++++++++//+TargetObject+DependencyProperty.

++++++++///+<summary>
++++++++///+Specifies+the+object+upon+which+to+set+the+property.
++++++++///+</summary>
++++++++public+object+TargetObject
++++++++{
++++++++++++get+{+return+GetValue(TargetObjectProperty);+}
++++++++++++set+{+SetValue(TargetObjectProperty,+value);+}
++++++++}

++++++++public+static+readonly+DependencyProperty+TargetObjectProperty
++++++++++++=+DependencyProperty.Register("TargetObject",+typeof(object),
++++++++++++typeof(SetPropertyAction));


++++++++//+Private+Implementation.

++++++++protected+override+void+Invoke(object+parameter)
++++++++{
++++++++++++object+target+=+TargetObject+??+AssociatedObject;
++++++++++++PropertyInfo+propertyInfo+=+target.GetType().GetProperty(
++++++++++++++++PropertyName,
++++++++++++++++BindingFlags.Instance%7CBindingFlags.Public
++++++++++++++++%7CBindingFlags.NonPublic%7CBindingFlags.InvokeMethod);

++++++++++++propertyInfo.SetValue(target,+PropertyValue);
++++++++}
++++}
}|code-block|syntax|javascript|338549|在本例中，我绑定到视图模型上一个名为DialogResult的属性。|338550|​|338551|<Grid>

++++<Button>
++++++++<i:Interaction.Triggers>
++++++++++++<i:EventTrigger+EventName="Click">
++++++++++++++++<wpf:SetPropertyAction+PropertyName="DialogResult"+TargetObject="{Binding}"
+++++++++++++++++++++++++++++++++++++++PropertyValue="{x:Static+mvvm:DialogResult.Cancel}"/>
++++++++++++</i:EventTrigger>
++++++++</i:Interaction.Triggers>
++++++++Cancel
++++</Button>

</Grid>|338552|338553|entityMap^0|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|P|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|Q|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|R|8|@]|9|@]|A|$]]|$1|I|3|J|5|6|7|S|8|@]|9|@]|A|$]]|$1|K|3|L|5|D|7|T|8|@]|9|@]|A|$E|F]]|$1|M|3|J|5|6|7|U|8|@]|9|@]|A|$]]|$1|N|3|-4|5|6|7|V|8|@]|9|@]|A|$]]]|O|$]]

<p>Just create your own action.</p>

<pre class="lang-cs prettyprint-override"><code>namespace WpfUtil
{
    using System.Reflection;
    using System.Windows;
    using System.Windows.Interactivity;


    /// &lt;summary&gt;
    /// Sets the designated property to the supplied value. TargetObject
    /// optionally designates the object on which to set the property. If
    /// TargetObject is not supplied then the property is set on the object
    /// to which the trigger is attached.
    /// &lt;/summary&gt;
    public class SetPropertyAction : TriggerAction&lt;FrameworkElement&gt;
    {
        // PropertyName DependencyProperty.

        /// &lt;summary&gt;
        /// The property to be executed in response to the trigger.
        /// &lt;/summary&gt;
        public string PropertyName
        {
            get { return (string)GetValue(PropertyNameProperty); }
            set { SetValue(PropertyNameProperty, value); }
        }

        public static readonly DependencyProperty PropertyNameProperty
            = DependencyProperty.Register("PropertyName", typeof(string),
            typeof(SetPropertyAction));


        // PropertyValue DependencyProperty.

        /// &lt;summary&gt;
        /// The value to set the property to.
        /// &lt;/summary&gt;
        public object PropertyValue
        {
            get { return GetValue(PropertyValueProperty); }
            set { SetValue(PropertyValueProperty, value); }
        }

        public static readonly DependencyProperty PropertyValueProperty
            = DependencyProperty.Register("PropertyValue", typeof(object),
            typeof(SetPropertyAction));


        // TargetObject DependencyProperty.

        /// &lt;summary&gt;
        /// Specifies the object upon which to set the property.
        /// &lt;/summary&gt;
        public object TargetObject
        {
            get { return GetValue(TargetObjectProperty); }
            set { SetValue(TargetObjectProperty, value); }
        }

        public static readonly DependencyProperty TargetObjectProperty
            = DependencyProperty.Register("TargetObject", typeof(object),
            typeof(SetPropertyAction));


        // Private Implementation.

        protected override void Invoke(object parameter)
        {
            object target = TargetObject ?? AssociatedObject;
            PropertyInfo propertyInfo = target.GetType().GetProperty(
                PropertyName,
                BindingFlags.Instance|BindingFlags.Public
                |BindingFlags.NonPublic|BindingFlags.InvokeMethod);

            propertyInfo.SetValue(target, PropertyValue);
        }
    }
}
</code></pre>

<p>In this case I'm binding to a property called DialogResult on my viewmodel.</p>

<p></p>

<pre><code>&lt;Grid&gt;

    &lt;Button&gt;
        &lt;i:Interaction.Triggers&gt;
            &lt;i:EventTrigger EventName="Click"&gt;
                &lt;wpf:SetPropertyAction PropertyName="DialogResult" TargetObject="{Binding}"
                                       PropertyValue="{x:Static mvvm:DialogResult.Cancel}"/&gt;
            &lt;/i:EventTrigger&gt;
        &lt;/i:Interaction.Triggers&gt;
        Cancel
    &lt;/Button&gt;

&lt;/Grid&gt;
</code></pre>

<p></p>


blocks|key|3109554|text|我修改了Neutrino的解决方案，使xaml在指定值时看起来不那么冗长：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|3109555|很抱歉没有渲染的xaml图片，想象一下你点击一个=汉堡包按钮，它就变成了<-一个后退按钮，还切换了一个网格的可见性。|3109556|xmlns:i="clr-namespace:System.Windows.Interactivity;assembly=System.Windows.Interactivity"

...

<Grid>
++++<Button+x:Name="optionsButton">
++++++++<i:Interaction.Triggers>
++++++++++++<i:EventTrigger+EventName="Click">
++++++++++++++++<local:SetterAction+PropertyName="Visibility"+Value="Collapsed"+/>
++++++++++++++++<local:SetterAction+PropertyName="Visibility"+TargetObject="{Binding+ElementName=optionsBackButton}"+Value="Visible"+/>
++++++++++++++++<local:SetterAction+PropertyName="Visibility"+TargetObject="{Binding+ElementName=optionsPanel}"+Value="Visible"+/>
++++++++++++</i:EventTrigger>
++++++++</i:Interaction.Triggers>

++++++++<glyphs:Hamburger+Width="10"+Height="10"+/>
++++</Button>

++++<Button+x:Name="optionsBackButton"+Visibility="Collapsed">
++++++++<i:Interaction.Triggers>
++++++++++++<i:EventTrigger+EventName="Click">
++++++++++++++++<local:SetterAction+PropertyName="Visibility"+Value="Collapsed"+/>
++++++++++++++++<local:SetterAction+PropertyName="Visibility"+TargetObject="{Binding+ElementName=optionsButton}"+Value="Visible"+/>
++++++++++++++++<local:SetterAction+PropertyName="Visibility"+TargetObject="{Binding+ElementName=optionsPanel}"+Value="Collapsed"+/>
++++++++++++</i:EventTrigger>
++++++++</i:Interaction.Triggers>

++++++++<glyphs:Back+Width="12"+Height="11"+/>
++++</Button>
</Grid>

...

<Grid+Grid.RowSpan="2"+x:Name="optionsPanel"+Visibility="Collapsed">

</Grid>|code-block|syntax|javascript|3109557|您还可以像在中微子的解决方案中那样指定值：|3109558|<Button+x:Name="optionsButton">
++++<i:Interaction.Triggers>
++++++++<i:EventTrigger+EventName="Click">
++++++++++++<local:SetterAction+PropertyName="Visibility"+Value="{x:Static+Visibility.Collapsed}"+/>
++++++++++++<local:SetterAction+PropertyName="Visibility"+TargetObject="{Binding+ElementName=optionsBackButton}"+Value="{x:Static+Visibility.Visible}"+/>
++++++++++++<local:SetterAction+PropertyName="Visibility"+TargetObject="{Binding+ElementName=optionsPanel}"+Value="{x:Static+Visibility.Visible}"+/>
++++++++</i:EventTrigger>
++++</i:Interaction.Triggers>

++++<glyphs:Hamburger+Width="10"+Height="10"+/>
</Button>|3109559|这是代码。|3109560|using+System;
using+System.ComponentModel;
using+System.Reflection;
using+System.Windows;
using+System.Windows.Interactivity;

namespace+Mvvm.Actions
{
++++///+<summary>
++++///+Sets+a+specified+property+to+a+value+when+invoked.
++++///+</summary>
++++public+class+SetterAction+:+TargetedTriggerAction<FrameworkElement>
++++{
++++++++#region+Properties

++++++++#region+PropertyName

++++++++///+<summary>
++++++++///+Property+that+is+being+set+by+this+setter.
++++++++///+</summary>
++++++++public+string+PropertyName
++++++++{
++++++++++++get+{+return+(string)GetValue(PropertyNameProperty);+}
++++++++++++set+{+SetValue(PropertyNameProperty,+value);+}
++++++++}

++++++++public+static+readonly+DependencyProperty+PropertyNameProperty+=
++++++++++++DependencyProperty.Register("PropertyName",+typeof(string),+typeof(SetterAction),
++++++++++++new+PropertyMetadata(String.Empty));

++++++++#endregion

++++++++#region+Value

++++++++///+<summary>
++++++++///+Property+value+that+is+being+set+by+this+setter.
++++++++///+</summary>
++++++++public+object+Value
++++++++{
++++++++++++get+{+return+(object)GetValue(ValueProperty);+}
++++++++++++set+{+SetValue(ValueProperty,+value);+}
++++++++}

++++++++public+static+readonly+DependencyProperty+ValueProperty+=
++++++++++++DependencyProperty.Register("Value",+typeof(object),+typeof(SetterAction),
++++++++++++new+PropertyMetadata(null));

++++++++#endregion

++++++++#endregion

++++++++#region+Overrides

++++++++protected+override+void+Invoke(object+parameter)
++++++++{
++++++++++++var+target+=+TargetObject+??+AssociatedObject;

++++++++++++var+targetType+=+target.GetType();

++++++++++++var+property+=+targetType.GetProperty(PropertyName,+BindingFlags.NonPublic+%7C+BindingFlags.Public+%7C+BindingFlags.Static+%7C+BindingFlags.Instance);
++++++++++++if+(property+==+null)
++++++++++++++++throw+new+ArgumentException(String.Format("Property+not+found:+{0}",+PropertyName));

++++++++++++if+(property.CanWrite+==+false)
++++++++++++++++throw+new+ArgumentException(String.Format("Property+is+not+settable:+{0}",+PropertyName));

++++++++++++object+convertedValue;

++++++++++++if+(Value+==+null)
++++++++++++++++convertedValue+=+null;

++++++++++++else
++++++++++++{
++++++++++++++++var+valueType+=+Value.GetType();
++++++++++++++++var+propertyType+=+property.PropertyType;

++++++++++++++++if+(valueType+==+propertyType)
++++++++++++++++++++convertedValue+=+Value;

++++++++++++++++else
++++++++++++++++{
++++++++++++++++++++var+propertyConverter+=+TypeDescriptor.GetConverter(propertyType);

++++++++++++++++++++if+(propertyConverter.CanConvertFrom(valueType))
++++++++++++++++++++++++convertedValue+=+propertyConverter.ConvertFrom(Value);

++++++++++++++++++++else+if+(valueType.IsSubclassOf(propertyType))
++++++++++++++++++++++++convertedValue+=+Value;

++++++++++++++++++++else
++++++++++++++++++++++++throw+new+ArgumentException(String.Format("Cannot+convert+type+'{0}'+to+'{1}'.",+valueType,+propertyType));
++++++++++++++++}
++++++++++++}

++++++++++++property.SetValue(target,+convertedValue);
++++++++}

++++++++#endregion
++++}
}|3109561|entityMap^0|0|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|S|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|T|8|@]|9|@]|A|$]]|$1|D|3|E|5|F|7|U|8|@]|9|@]|A|$G|H]]|$1|I|3|J|5|6|7|V|8|@]|9|@]|A|$]]|$1|K|3|L|5|F|7|W|8|@]|9|@]|A|$G|H]]|$1|M|3|N|5|6|7|X|8|@]|9|@]|A|$]]|$1|O|3|P|5|F|7|Y|8|@]|9|@]|A|$G|H]]|$1|Q|3|-4|5|6|7|Z|8|@]|9|@]|A|$]]]|R|$]]

<p>I modified Neutrino's solution to make the xaml look less verbose when specifying the value:</p>

<p>Sorry for no pictures of the rendered xaml, just imagine a [=] hamburger button that you click and it turns into [&lt;-] a back button and also toggles the visibility of a Grid.</p>

<pre><code>xmlns:i="clr-namespace:System.Windows.Interactivity;assembly=System.Windows.Interactivity"

...

&lt;Grid&gt;
    &lt;Button x:Name="optionsButton"&gt;
        &lt;i:Interaction.Triggers&gt;
            &lt;i:EventTrigger EventName="Click"&gt;
                &lt;local:SetterAction PropertyName="Visibility" Value="Collapsed" /&gt;
                &lt;local:SetterAction PropertyName="Visibility" TargetObject="{Binding ElementName=optionsBackButton}" Value="Visible" /&gt;
                &lt;local:SetterAction PropertyName="Visibility" TargetObject="{Binding ElementName=optionsPanel}" Value="Visible" /&gt;
            &lt;/i:EventTrigger&gt;
        &lt;/i:Interaction.Triggers&gt;

        &lt;glyphs:Hamburger Width="10" Height="10" /&gt;
    &lt;/Button&gt;

    &lt;Button x:Name="optionsBackButton" Visibility="Collapsed"&gt;
        &lt;i:Interaction.Triggers&gt;
            &lt;i:EventTrigger EventName="Click"&gt;
                &lt;local:SetterAction PropertyName="Visibility" Value="Collapsed" /&gt;
                &lt;local:SetterAction PropertyName="Visibility" TargetObject="{Binding ElementName=optionsButton}" Value="Visible" /&gt;
                &lt;local:SetterAction PropertyName="Visibility" TargetObject="{Binding ElementName=optionsPanel}" Value="Collapsed" /&gt;
            &lt;/i:EventTrigger&gt;
        &lt;/i:Interaction.Triggers&gt;

        &lt;glyphs:Back Width="12" Height="11" /&gt;
    &lt;/Button&gt;
&lt;/Grid&gt;

...

&lt;Grid Grid.RowSpan="2" x:Name="optionsPanel" Visibility="Collapsed"&gt;

&lt;/Grid&gt;
</code></pre>

<p>You can also specify values this way like in Neutrino's solution:</p>

<pre><code>&lt;Button x:Name="optionsButton"&gt;
    &lt;i:Interaction.Triggers&gt;
        &lt;i:EventTrigger EventName="Click"&gt;
            &lt;local:SetterAction PropertyName="Visibility" Value="{x:Static Visibility.Collapsed}" /&gt;
            &lt;local:SetterAction PropertyName="Visibility" TargetObject="{Binding ElementName=optionsBackButton}" Value="{x:Static Visibility.Visible}" /&gt;
            &lt;local:SetterAction PropertyName="Visibility" TargetObject="{Binding ElementName=optionsPanel}" Value="{x:Static Visibility.Visible}" /&gt;
        &lt;/i:EventTrigger&gt;
    &lt;/i:Interaction.Triggers&gt;

    &lt;glyphs:Hamburger Width="10" Height="10" /&gt;
&lt;/Button&gt;
</code></pre>

<p>And here's the code.</p>

<pre><code>using System;
using System.ComponentModel;
using System.Reflection;
using System.Windows;
using System.Windows.Interactivity;

namespace Mvvm.Actions
{
    /// &lt;summary&gt;
    /// Sets a specified property to a value when invoked.
    /// &lt;/summary&gt;
    public class SetterAction : TargetedTriggerAction&lt;FrameworkElement&gt;
    {
        #region Properties

        #region PropertyName

        /// &lt;summary&gt;
        /// Property that is being set by this setter.
        /// &lt;/summary&gt;
        public string PropertyName
        {
            get { return (string)GetValue(PropertyNameProperty); }
            set { SetValue(PropertyNameProperty, value); }
        }

        public static readonly DependencyProperty PropertyNameProperty =
            DependencyProperty.Register("PropertyName", typeof(string), typeof(SetterAction),
            new PropertyMetadata(String.Empty));

        #endregion

        #region Value

        /// &lt;summary&gt;
        /// Property value that is being set by this setter.
        /// &lt;/summary&gt;
        public object Value
        {
            get { return (object)GetValue(ValueProperty); }
            set { SetValue(ValueProperty, value); }
        }

        public static readonly DependencyProperty ValueProperty =
            DependencyProperty.Register("Value", typeof(object), typeof(SetterAction),
            new PropertyMetadata(null));

        #endregion

        #endregion

        #region Overrides

        protected override void Invoke(object parameter)
        {
            var target = TargetObject ?? AssociatedObject;

            var targetType = target.GetType();

            var property = targetType.GetProperty(PropertyName, BindingFlags.NonPublic | BindingFlags.Public | BindingFlags.Static | BindingFlags.Instance);
            if (property == null)
                throw new ArgumentException(String.Format("Property not found: {0}", PropertyName));

            if (property.CanWrite == false)
                throw new ArgumentException(String.Format("Property is not settable: {0}", PropertyName));

            object convertedValue;

            if (Value == null)
                convertedValue = null;

            else
            {
                var valueType = Value.GetType();
                var propertyType = property.PropertyType;

                if (valueType == propertyType)
                    convertedValue = Value;

                else
                {
                    var propertyConverter = TypeDescriptor.GetConverter(propertyType);

                    if (propertyConverter.CanConvertFrom(valueType))
                        convertedValue = propertyConverter.ConvertFrom(Value);

                    else if (valueType.IsSubclassOf(propertyType))
                        convertedValue = Value;

                    else
                        throw new ArgumentException(String.Format("Cannot convert type '{0}' to '{1}'.", valueType, propertyType));
                }
            }

            property.SetValue(target, convertedValue);
        }

        #endregion
    }
}
</code></pre>


<p>I want to be able to set a property with an EventTrigger, there's a number of problems with this.</p>

<p>1)  EventTriggers only support Actions, so I must use a storyBoard to set my properties.</p>

<p>2)  Once I use a storyboard, I have two options:</p>

<ul>
<li>Stop:  Once the animation has stopped the value reverts back to before the animation started</li>
<li>HoldEnd:  This locks the property, so that neither code, nor user interaction can change the property that the animation is holding.</li>
</ul>

<p>In the below example, I want to set the IsChecked property to False when the button is clicked and I want the user to be able to change the IsChecked and/or I want to be able to change the property in code.</p>

<p>Example:</p>

<pre><code>&lt;EventTrigger
    SourceName="myButton"
    RoutedEvent="Button.Click"&gt;
    &lt;EventTrigger.Actions&gt;
        &lt;BeginStoryboard&gt;
            &lt;Storyboard&gt;
                &lt;BooleanAnimationUsingKeyFrames
                    Storyboard.TargetName="myCheckBox"
                    Storyboard.TargetProperty="IsChecked"
                    FillBehavior="Stop"&gt;
                    &lt;DiscreteBooleanKeyFrame
                        KeyTime="00:00:00"
                        Value="False" /&gt;
                &lt;/BooleanAnimationUsingKeyFrames&gt;
            &lt;/Storyboard&gt;
        &lt;/BeginStoryboard&gt;
    &lt;/EventTrigger.Actions&gt;
&lt;/EventTrigger&gt;
</code></pre>

<p>I realize that I can use the "Completed" event after the storyboard completes to set the value to False.  However, in this instance I want to contain the logic within the XAML, as this logic will be used on a custom control and is only specific to the UI.</p>


Setting a property with an EventTrigger

翻译质量差，导致语言生硬或混乱。

没有提供实际的解决方法或示例。

解答不清晰，无法理解或解决问题。

页面排版不美观，阅读体验差。

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我希望能够使用EventTrigger来设置属性，这有很多问题。1) EventTriggers只支持storyBoard，所以我必须使用Actions来设置我的属性。2)一旦我使用了故事板，我有两个选择：Stop:一旦动画停止，该值将恢复到动画startedHoldEnd:之前的状态。这样，无论是代码还是用户交互都不...

问使用EventTrigger设置属性
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