更新:这是自从我安装了VS2012 RC之后出现的问题。(呃,很抱歉我应该说一下)。 我有一个WPF切换按钮。我想在它上面绘制一张图片,所以我创建了一个绘画笔刷,我想控制绘画的颜色,所以我将它绑定到ToggleButton的Foreground属性上。然而似乎不起作用?(在下面的例子中,绘画应该是蓝色的,但是它是黑色的)。
<UserControl x:Class="SynthEditWpf.UserControl1"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
mc:Ignorable="d"
d:DesignHeight="300" d:DesignWidth="300">
<UserControl.Resources>
<DrawingBrush x:Key="Power" Stretch="None">
<DrawingBrush.Drawing>
<DrawingGroup>
<DrawingGroup.Children>
<GeometryDrawing Geometry="F1 M 11.9999,4.34296L 11.9999,9.57471">
<GeometryDrawing.Pen>
<Pen Thickness="3" StartLineCap="Round" EndLineCap="Round" LineJoin="Round" Brush="{Binding Path=Foreground, RelativeSource={RelativeSource AncestorType={x:Type Control}}}"/>
</GeometryDrawing.Pen>
</GeometryDrawing>
<GeometryDrawing Geometry="F1 M 7.60373,6.78986C 6.09436,8.03101 5.13317,9.90375 5.13317,11.999C 5.13317,15.7359 8.19123,18.7654 11.9635,18.7654C 15.7359,18.7654 18.7939,15.7359 18.7939,11.999C 18.7939,9.90375 17.8327,8.03101 16.3234,6.78986">
<GeometryDrawing.Pen>
<Pen Thickness="3" StartLineCap="Round" EndLineCap="Round" LineJoin="Round" Brush="{Binding Path=Foreground, RelativeSource={RelativeSource AncestorType={x:Type Control}}}"/>
</GeometryDrawing.Pen>
</GeometryDrawing>
</DrawingGroup.Children>
</DrawingGroup>
</DrawingBrush.Drawing>
</DrawingBrush>
</UserControl.Resources>
<Grid>
<ToggleButton Foreground="Blue" Width="30" Height="30">
<Rectangle Fill="{StaticResource Power}" Width="24" Height="24" />
</ToggleButton>
</Grid>
</UserControl>
跟踪输出
System.Windows.Data警告:55:为绑定(hash=30868550)创建了BindingExpression(hash=9381496)。 System.Windows.Data警告:57:路径:'Foreground' System.Windows.Data警告:59:BindingExpression(hash=9381496):默认模式解析为OneWay System.Windows.Data警告:60:BindingExpression(hash=9381496):默认更新触发程序解析为PropertyChanged System.Windows.Data警告:61:BindingExpression(hash=9381496):附加到System.Windows.Media.Pen.Brush(hash=13172414) System.Windows.Data警告:65:BindingExpression(hash=9381496):RelativeSource(FindAncestor)需要树上下文 System.Windows.Data警告:64:BindingExpression(hash=9381496):解析源被延迟