在DrawingBrush中设置值

Question

我有一支画笔

<DrawingBrush x:Key="ICON" Viewbox="0,0,39.125,39.125" ViewboxUnits="Absolute">
    <DrawingBrush.Drawing>
        <GeometryDrawing Brush="{Binding RelativeSource={RelativeSource FindAncestor, AncestorType=uiEntityViews:BaseView}, Path=MeSiteColor, FallBackValue=Gray}" Geometry="F1M19.5625,0.999954C29.8144,0.999954 38.125,9.31053 38.125,19.5625 38.125,29.8142 29.8143,38.1249 19.5625,38.1249 9.31073,38.1249 1,29.8142 1,19.5625 1,9.31053 9.31064,0.999954 19.5625,0.999954z">
            <GeometryDrawing.Pen>
                <Pen DashCap="Square" EndLineCap="Flat" LineJoin="Round" MiterLimit="10" StartLineCap="Flat" Thickness="2">
                    <Pen.Brush>
                        <LinearGradientBrush EndPoint="0.849422,0.849423" StartPoint="0.150577,0.150578">
                            <GradientStop Color="#FF657783" Offset="0"/>
                            <GradientStop Color="White" Offset="0.146"/>
                            <GradientStop Color="#FF2C4758" Offset="1"/>
                        </LinearGradientBrush>
                    </Pen.Brush>
                    <Pen.DashStyle>
                        <DashStyle/>
                    </Pen.DashStyle>
                </Pen>
            </GeometryDrawing.Pen>
        </GeometryDrawing>
    </DrawingBrush.Drawing>
</DrawingBrush>

我想设置FallBackValue的颜色，让我们说灰色，以防绑定失败。但是，使用上面的代码，我将得到以下错误

Error 587 Unknown property 'FallBackValue' for type 'System.Windows.Data.Binding' encountered while parsing a Markup Extension。

Answer 1

我是FallbackValue，不是FallBackValue。(请注意案件中的差异)