我创建了一个依赖属性但由于某种原因它似乎失败了,它必须与绑定有关但我看不清楚。依赖属性如下:
public class HighlightColour
{
#region HighlightColour dependency property
public static readonly DependencyProperty sm_ValueProperty;
public static Color GetValue(DependencyObject obj)
{
return (Color)obj.GetValue(sm_ValueProperty);
}
public static void SetValue(DependencyObject obj, Color value)
{
obj.SetValue(sm_ValueProperty, value);
}
#endregion
static HighlightColour()
{
var metadata = new FrameworkPropertyMetadata(Colors.Transparent);
sm_ValueProperty = DependencyProperty.RegisterAttached("Value",
typeof(Color),
typeof(HighlightColour), metadata);
}
}
在XAML中我试图在样式模板中绑定它并设置按钮的背景颜色:
<Style x:Key="CommonButton" TargetType="Button">
<Setter Property="FontFamily" Value="Tahoma"/>
<Setter Property="FontSize" Value="12"/>
<Setter Property="custprop:HighlightColour.Value" Value="Red"/>
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type Button}">
<Grid Margin="0">
<Border Name="ButtonBody" Background="{TemplateBinding Background}" BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="1" CornerRadius="12,12,12,12" />
<Border Name="Highlight" Opacity="0" BorderThickness="0" CornerRadius="12,12,12,12">
<Border.Background>
<SolidColorBrush Color="{Binding Path=(custprop:HighlightColour.Value), Source={RelativeSource FindAncestor,AncestorType={x:Type Button}}}"/>
</Border.Background>
</Border>
<ContentPresenter Name="content" HorizontalAlignment="Center" VerticalAlignment="Center" />
</Grid>
<ControlTemplate.Triggers>
<Trigger Property="IsMouseOver" Value="True">
<Trigger.EnterActions>
<BeginStoryboard Name="HighlightAnim">
<Storyboard TargetName="Highlight" TargetProperty="Opacity" AutoReverse="True" RepeatBehavior="Forever">
<DoubleAnimation From="1" To="0.2" Duration="00:00:01"/>
</Storyboard>
</BeginStoryboard>
</Trigger.EnterActions>
<Trigger.ExitActions>
<StopStoryboard BeginStoryboardName="HighlightAnim"/>
</Trigger.ExitActions>
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
由于某种原因,它失败了,我看到了错误,例如:
无法从''获取'价值'值(输入'颜色')(类型 '的RelativeSource')。 BindingExpression:路径=(0); DataItem ='RelativeSource'(HashCode = 60828848);目标元素是 'SolidColorBrush'(HashCode = 10588721);目标属性是'颜色' (输入'Color')InvalidCastException:'System.InvalidCastException: 无法将“System.Windows.Data.RelativeSource”类型的对象强制转换为 输入'System.Windows.DependencyObject'。
答案 0 :(得分:2)
变化:
<SolidColorBrush Color="{Binding Path=(custprop:HighlightColour.Value),
Source={RelativeSource FindAncestor,AncestorType={x:Type Button}}}" />
要:
<SolidColorBrush Color="{Binding Path=(custprop:HighlightColour.Value),
RelativeSource={RelativeSource FindAncestor,AncestorType={x:Type Button}}}" />
有关绑定的详细信息:MSDN或this cheat sheet
答案 1 :(得分:0)
请勿使用sm_
作为前缀,否则WPF将无法“找到”您的DP。