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如何在资源中使用绑定来避免错误？

我现在正在研究我的第一个 wpf 项目。我在以下控件Style中Windows.Resource加入了参考。

<Window.Resources>
<Style x:Key="EmojiButtonStyle" TargetType="{x:Type Button}">
            <Setter Property="FocusVisualStyle" Value="{StaticResource FocusVisual}" />
            <Setter Property="Background" Value="Transparent" />
            <Setter Property="BorderBrush" Value="Transparent" />
            <Setter Property="Foreground" Value="{DynamicResource {x:Static SystemColors.ControlTextBrushKey}}" />
            <Setter Property="BorderThickness" Value="0" />
            <Setter Property="HorizontalContentAlignment" Value="Center" />
            <Setter Property="VerticalContentAlignment" Value="Center" />
            <Setter Property="Padding" Value="1" />
            <Setter Property="Effect">
                <Setter.Value>
                    <DropShadowEffect
                        BlurRadius="4"
                        Opacity="1.0"
                        ShadowDepth="0"
                        Color="Gray" />
                </Setter.Value>
            </Setter>
            <Setter Property="Template">
                <Setter.Value>
                    <ControlTemplate TargetType="{x:Type Button}">
                        <Border
                            x:Name="border"
                            Background="{TemplateBinding Background}"
                            BorderBrush="{TemplateBinding BorderBrush}"
                            BorderThickness="{TemplateBinding BorderThickness}"
                            SnapsToDevicePixels="true">
                            <ContentPresenter
                                x:Name="contentPresenter"
                                Margin="{TemplateBinding Padding}"
                                HorizontalAlignment="{TemplateBinding HorizontalContentAlignment}"
                                VerticalAlignment="{TemplateBinding VerticalContentAlignment}"
                                Focusable="False"
                                RecognizesAccessKey="True"
                                SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}" />
                        </Border>
                        <ControlTemplate.Triggers>
                            <Trigger Property="IsDefaulted" Value="true" />
                            <Trigger Property="IsMouseOver" Value="true">
                                <Setter Property="TextBlock.Effect">
                                    <Setter.Value>
                                        <DropShadowEffect
                                            BlurRadius="5"
                                            ShadowDepth="0"
                                            Color="{Binding RelativeSource={RelativeSource Mode=FindAncestor, AncestorType=Button}, Path=Foreground, Mode=OneWay, Converter={StaticResource SingleValueDebugPrintConverter}}" />
                                    </Setter.Value>
                                </Setter>
                                <Setter Property="Foreground" Value="OrangeRed" />
                            </Trigger>
                            <Trigger Property="IsPressed" Value="true">
                                <Setter Property="TextBlock.Effect">
                                    <Setter.Value>
                                        <DropShadowEffect
                                            BlurRadius="2"
                                            ShadowDepth="0"
                                            Color="{Binding RelativeSource={RelativeSource Mode=FindAncestor, AncestorType=Button}, Path=Foreground, Mode=OneWay, Converter={StaticResource SingleValueDebugPrintConverter}}" />
                                    </Setter.Value>
                                </Setter>
                                <Setter Property="Foreground" Value="DarkRed" />
                            </Trigger>
                            <Trigger Property="IsEnabled" Value="false">
                                <Setter TargetName="contentPresenter" Property="TextElement.Foreground" Value="LightGray" />
                            </Trigger>
                        </ControlTemplate.Triggers>
                    </ControlTemplate>
                </Setter.Value>
            </Setter>
        </Style>
    </Window.Resources>

它运行良好，但是在应用程序启动时出现错误。

System.Windows.Data Error: 2 : Cannot find governing FrameworkElement or FrameworkContentElement for target element. BindingExpression:Path=Foreground; DataItem=null; target element is 'DropShadowEffect' (HashCode=65300541); target property is 'Color' (type 'Color')

我确定错误是由于Color="{Binding RelativeSource={RelativeSource Mode=FindAncestor, AncestorType=Button}, Path=Foreground, Mode=OneWay, Converter={StaticResource SingleValueDebugPrintConverter}}"，在被其他控件引用之前，绑定Windows.Resource没有祖先。

我这样做是否正确？错误是可以避免的吗？

更新#1

几个小时以来一直在研究类似的问题，但没有一个与我遇到的问题相符。

绑定目标需要是可视化树的一部分。资源字典中没有数据上下文。确切的修复将取决于您的场景细节。有关一般性建议，请参阅副本。——彼得·杜尼霍

Peter Duniho 的回答可能解释了为什么bindinginWindow.Resource不起作用，但我找不到任何解决方法。ProxyElement其他帖子中提到的技巧是绑定到DataContextnot Ancestor。

更新#2

无论如何，我找到了正确的方法。使用TemplateBinding而不是FindAncestor.

<Window.Resources>
<Style x:Key="EmojiButtonStyle" TargetType="{x:Type Button}">
            <Setter Property="FocusVisualStyle" Value="{StaticResource FocusVisual}" />
            <Setter Property="Background" Value="Transparent" />
            <Setter Property="BorderBrush" Value="Transparent" />
            <Setter Property="Foreground" Value="{DynamicResource {x:Static SystemColors.ControlTextBrushKey}}" />
            <Setter Property="BorderThickness" Value="0" />
            <Setter Property="HorizontalContentAlignment" Value="Center" />
            <Setter Property="VerticalContentAlignment" Value="Center" />
            <Setter Property="Padding" Value="1" />
            <Setter Property="Effect">
                <Setter.Value>
                    <DropShadowEffect
                        BlurRadius="4"
                        Opacity="1.0"
                        ShadowDepth="0"
                        Color="Gray" />
                </Setter.Value>
            </Setter>
            <Setter Property="Cursor" Value="Hand" />
            <Setter Property="Template">
                <Setter.Value>
                    <ControlTemplate TargetType="{x:Type Button}">
                        <Border
                            x:Name="border"
                            Background="{TemplateBinding Background}"
                            BorderBrush="{TemplateBinding BorderBrush}"
                            BorderThickness="{TemplateBinding BorderThickness}"
                            SnapsToDevicePixels="true">
                            <ContentPresenter
                                x:Name="contentPresenter"
                                Margin="{TemplateBinding Padding}"
                                HorizontalAlignment="{TemplateBinding HorizontalContentAlignment}"
                                VerticalAlignment="{TemplateBinding VerticalContentAlignment}"
                                Focusable="False"
                                RecognizesAccessKey="True"
                                SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}" />
                        </Border>
                        <ControlTemplate.Triggers>
                            <Trigger Property="IsMouseOver" Value="true">
                                <Setter Property="TextBlock.Effect">
                                    <Setter.Value>
                                        <DropShadowEffect
                                            BlurRadius="8"
                                            ShadowDepth="0"
                                            Color="{TemplateBinding Property=Foreground}" />
                                    </Setter.Value>
                                </Setter>
                            </Trigger>
                            <Trigger Property="IsPressed" Value="true">
                                <Setter Property="TextBlock.Effect">
                                    <Setter.Value>
                                        <DropShadowEffect
                                            BlurRadius="3"
                                            ShadowDepth="0"
                                            Color="{TemplateBinding Property=Foreground}" />
                                    </Setter.Value>
                                </Setter>
                            </Trigger>
                            <Trigger Property="IsEnabled" Value="false">
                                <Setter TargetName="contentPresenter" Property="TextElement.Foreground" Value="LightGray" />
                            </Trigger>
                        </ControlTemplate.Triggers>
                    </ControlTemplate>
                </Setter.Value>
            </Setter>
        </Style>
</Window.Resources>

感谢样式和模板 (WPF .NET)。Stackoverflow 确实需要先审查某人的问题，然后再将其作为duplicate.

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