我有一个标准样式用于我的按钮,但我希望样式的某些部分可以配置。例如,当触发鼠标悬停在按钮上时,我希望边框出现,并且我想可配置边框颜色。
根据这篇文章:http://www.thomaslevesque.com/2011/10/01/wpf-creating-parameterized-styles-with-attached-properties/,我认为我可以使用附加属性和TemplateBinding来实现这一点。
我创建了以下附加属性:
public static class ThemeProperties
{
public static Brush GetButtonBorderColour(DependencyObject obj)
{
return (Brush)obj.GetValue(ButtonBorderColourProperty);
}
public static void SetButtonBorderColour(DependencyObject obj, Brush value)
{
obj.SetValue(ButtonBorderColourProperty, value);
}
public static readonly DependencyProperty ButtonBorderColourProperty =
DependencyProperty.RegisterAttached(
"ButtonBorderColour",
typeof(Brush),
typeof(ThemeProperties),
new FrameworkPropertyMetadata(Brushes.Black, FrameworkPropertyMetadataOptions.Inherits));
}
我这样设置属性:
<Button Style="{StaticResource RedButton}" local:ThemeProperties.ButtonBorderColour="#B20000"/>
我的样式看起来像这样:
<Window.Resources>
<Style x:Key="RedButton" TargetType="Button">
<Setter Property="OverridesDefaultStyle" Value="True"/>
<Setter Property="Margin" Value="2"/>
<Setter Property="FontFamily" Value="Tahoma"/>
<Setter Property="FontSize" Value="11px"/>
<Setter Property="FontWeight" Value="Bold"/>
<Setter Property="Foreground" Value="White"/>
<Setter Property="MinHeight" Value="25" />
<Setter Property="FocusVisualStyle" Value="{StaticResource MyFocusVisual}" />
<Setter Property="Background" >
<Setter.Value>
<LinearGradientBrush StartPoint="0,0" EndPoint="0,1" >
<GradientStop Color="#FECCBF" Offset="0.2"/>
<GradientStop Color="Red" Offset="0.85"/>
<GradientStop Color="#FECCBF" Offset="1"/>
</LinearGradientBrush>
</Setter.Value>
</Setter>
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="Button">
<Border Name="border" BorderThickness="1" Padding="4,2" BorderBrush="Transparent" CornerRadius="3" Background="{TemplateBinding Background}">
<Grid >
<ContentPresenter HorizontalAlignment="Center" VerticalAlignment="Center" Name="content"/>
</Grid>
</Border>
<ControlTemplate.Triggers>
<Trigger Property="IsMouseOver" Value="True">
<Setter TargetName="border" Property="BorderBrush" Value="{TemplateBinding local:ThemeProperties.ButtonBorderColour}" />
<Setter Property="Foreground" Value="#B20000" />
</Trigger>
<Trigger Property="IsPressed" Value="True">
<Setter Property="Background" >
<Setter.Value>
<LinearGradientBrush StartPoint="0,0" EndPoint="0,1" >
<GradientStop Color="#FECCBF" Offset="0.35"/>
<GradientStop Color="Red" Offset="0.95"/>
<GradientStop Color="#FECCBF" Offset="1"/>
</LinearGradientBrush>
</Setter.Value>
</Setter>
<Setter TargetName="content" Property="RenderTransform" >
<Setter.Value>
<TranslateTransform Y="1.0" />
</Setter.Value>
</Setter>
</Trigger>
<Trigger Property="IsDefaulted" Value="True">
<Setter TargetName="border" Property="BorderBrush" Value="#B20000" />
</Trigger>
<Trigger Property="IsFocused" Value="True">
<Setter TargetName="border" Property="BorderBrush" Value="#B20000" />
</Trigger>
<Trigger Property="IsEnabled" Value="False">
<Setter TargetName="border" Property="Opacity" Value="0.7" />
<Setter Property="Foreground" Value="Gray" />
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
</Window.Resources>
关键行是:
<Trigger Property="IsMouseOver" Value="True">
<Setter TargetName="border" Property="BorderBrush" Value="{TemplateBinding local:ThemeProperties.ButtonBorderColour}" />
<Setter Property="Foreground" Value="#B20000" />
</Trigger>
据我所知,这段代码应该能够正常工作,但是在上面这一行运行时出现了以下错误:
无法将属性“Value”中的值转换为类型为“”的对象。 在标记文件中的对象“System.Windows.Setter”处发生错误。
我做错了什么?我刚开始接触WPF,但无法弄清楚问题所在,因为附加属性的类型是Brush,而这正是我期望Border的BorderBrush属性需要的。
Value={TemplateBinding local:ThemeProperties.ButtonBorderColour}
。请注意,绑定表达式周围缺少括号。 - Leon Bohmann