I am overlaying several XAML-defined drawing groups in a resource dictionary, and noticed some strange behavior. If I define a DrawingImage thus:
<DrawingImage x:Key="My_Icon">
<DrawingImage.Drawing>
<DrawingGroup>
<DrawingGroup.Children>
<StaticResource ResourceKey="Background" />
<StaticResource ResourceKey="Foreground" />
<DrawingGroup>
<!-- some content here for an overlay -->
</DrawingGroup>
</DrawingGroup.Children>
</DrawingGroup>
</DrawingImage.Drawing>
</DrawingImage>
things work fine at design time, but at runtime I get an exception:
'XAML Node Stream: Value of 'System.Windows.Markup.StaticResourceHolder' must follow a StartObject and StartMember.' Line number '14' and line position '22'.
However, if I insert an empty DrawingGroup tag before my static resources, everything works fine:
<DrawingImage x:Key="My_Icon">
<DrawingImage.Drawing>
<DrawingGroup>
<DrawingGroup.Children>
<DrawingGroup />
<StaticResource ResourceKey="Background" />
<StaticResource ResourceKey="Foreground" />
<DrawingGroup>
<!-- some content here for an overlay -->
</DrawingGroup>
</DrawingGroup.Children>
</DrawingGroup>
</DrawingImage.Drawing>
</DrawingImage>
Does anyone know why this occurs? I am assuming it is a general XAML node processing bug and not specific to DrawingGroups, but I could be wrong...
Note that the StaticResources in question are DrawingGroups:
<DrawingGroup x:Key="Background">
<DrawingGroup.Children>
<GeometryDrawing Geometry="M 3,1.00001L 29,1.00001C 30.1046,1.00001 31,1.89544 31,3.00001L 31,29C 31,30.1046 30.1046,31 29,31L 3,31C 1.89543,31 1,30.1046 1,29L 1,3.00001C 1,1.89544 1.89543,1.00001 3,1.00001 Z ">
<GeometryDrawing.Pen>
<Pen LineJoin="Round" Brush="#FFEB8E00"/>
</GeometryDrawing.Pen>
<GeometryDrawing.Brush>
<RadialGradientBrush RadiusX="0.516666" RadiusY="0.516666" Center="0.499999,0.966667" GradientOrigin="0.499999,0.966667">
<RadialGradientBrush.GradientStops>
<GradientStop Color="#FFFFECA8" Offset="0"/>
<GradientStop Color="#FFFFCD52" Offset="0.2"/>
<GradientStop Color="#FFFFCD52" Offset="0.669767"/>
<GradientStop Color="#FFFFB100" Offset="0.95814"/>
</RadialGradientBrush.GradientStops>
<RadialGradientBrush.RelativeTransform>
<TransformGroup/>
</RadialGradientBrush.RelativeTransform>
</RadialGradientBrush>
</GeometryDrawing.Brush>
</GeometryDrawing>
<GeometryDrawing Brush="#67F9F0AD" Geometry="M 4,19L 28,19C 29.1046,19 30,19.8954 30,21L 30,28C 30,29.1046 29.1046,30 28,30L 4,30C 2.89543,30 2,29.1046 2,28L 2,21C 2,19.8954 2.89543,19 4,19 Z "/>
</DrawingGroup.Children>
</DrawingGroup>
My usage is simple- I am binding this whole DrawingImage to an Infragistics WPF button control:
<igWPF:ButtonTool igWPF:RibbonGroup.MaximumSize="ImageAndTextLarge" Caption="New Item" SmallImage="{StaticResource My_Icon}" LargeImage="{StaticResource My_Icon}" />