.net WPF按钮样式触发器

.net WPF按钮样式触发器,.net,wpf,.net,Wpf,我被WPF中的样式卡住了。当用户将鼠标悬停在按钮上时,我需要更改背景渐变,但我不知道如何进行更改。这是我目前掌握的代码: <Style x:Key="Button_Green" TargetType="{x:Type Button}"> <Setter Property="FontSize" Value="11" /> <Setter Property="Foreground" Value="White"/> <Sette

我被WPF中的样式卡住了。当用户将鼠标悬停在按钮上时,我需要更改背景渐变,但我不知道如何进行更改。这是我目前掌握的代码:

    <Style x:Key="Button_Green" TargetType="{x:Type Button}">
    <Setter Property="FontSize" Value="11" />
    <Setter Property="Foreground" Value="White"/>
    <Setter Property="Template">
        <Setter.Value>
            <ControlTemplate TargetType="{x:Type Button}">
                <Border CornerRadius="2" BorderBrush="#387f38" BorderThickness="1">
                    <Border.Background>
                        <LinearGradientBrush EndPoint="0.5,1" StartPoint="0.5,0">
                            <GradientStop Color="#FF5BB75B" Offset="0" />
                            <GradientStop Color="#FF449B44" Offset="1" />
                        </LinearGradientBrush>
                    </Border.Background>
                    <ContentPresenter x:Name="ButtonContentPresenter" VerticalAlignment="Center" HorizontalAlignment="Center"/>
                </Border>
            </ControlTemplate>
        </Setter.Value>
    </Setter>
    <Style.Triggers>
        <Trigger Property="IsMouseOver" Value="True">
            <Setter Property="Background">
                <Setter.Value>
                    <LinearGradientBrush EndPoint="0.5,1" StartPoint="0.5,0">
                        <GradientStop Color="#FF5BB75B" Offset="0" />
                        <GradientStop Color="#FF398239" Offset="1" />
                    </LinearGradientBrush>
                </Setter.Value>
            </Setter>
            <Setter Property="Cursor" Value="Hand" />
        </Trigger>
    </Style.Triggers>
</Style>


鼠标光标会正确更改,但背景渐变不会更改。

您需要将setter的目标设置为在
控制模板
中定义的
边框
元素。目前,它的目标是
按钮本身的
后台
属性,该属性由自定义
控制模板
隐藏

<Style x:Key="Button_Green" TargetType="{x:Type Button}">
<Setter Property="FontSize" Value="11" />
<Setter Property="Foreground" Value="White"/>
<Setter Property="Template">
    <Setter.Value>
        <ControlTemplate TargetType="{x:Type Button}">
            <Border x:Name="MyBackgroundElement" CornerRadius="2" BorderBrush="#387f38" BorderThickness="1">
                <Border.Background>
                    <LinearGradientBrush EndPoint="0.5,1" StartPoint="0.5,0">
                        <GradientStop Color="#FF5BB75B" Offset="0" />
                        <GradientStop Color="#FF449B44" Offset="1" />
                    </LinearGradientBrush>
                </Border.Background>
                <ContentPresenter x:Name="ButtonContentPresenter" VerticalAlignment="Center" HorizontalAlignment="Center"/>
            </Border>
            <ControlTemplate.Triggers>
                <Trigger Property="IsMouseOver" Value="True">
                    <Setter TargetName="MyBackgroundElement" Property="Background">
                        <Setter.Value>
                            <LinearGradientBrush EndPoint="0.5,1" StartPoint="0.5,0">
                                <GradientStop Color="#FF5BB75B" Offset="0" />
                                <GradientStop Color="#FF398239" Offset="1" />
                            </LinearGradientBrush>
                        </Setter.Value>
                    </Setter>
                    <Setter Property="Cursor" Value="Hand" />
               </Trigger>
            </ControlTemplate.Triggers>
        </ControlTemplate>
    </Setter.Value>
</Setter>
</Style>


在这里,我在
Border
元素中添加了
x:Name
属性,这样就可以使用
Setter
上的
TargetName
属性对其进行引用,从而从模板中更改此片段

<Border CornerRadius="2" BorderBrush="#387f38" BorderThickness="1">
   <Border.Background>
       <LinearGradientBrush EndPoint="0.5,1" StartPoint="0.5,0">
           <GradientStop Color="#FF5BB75B" Offset="0" />
           <GradientStop Color="#FF449B44" Offset="1" />
       </LinearGradientBrush>
   </Border.Background>
   <ContentPresenter x:Name="ButtonContentPresenter" VerticalAlignment="Center" HorizontalAlignment="Center"/>
</Border>
然后在样式中添加一个额外的setter,如下所示:

<Setter Property="Background">
  <Setter.Value>
      <LinearGradientBrush EndPoint="0.5,1" StartPoint="0.5,0">
          <GradientStop Color="#FF5BB75B" Offset="0" />
          <GradientStop Color="#FF449B44" Offset="1" />
      </LinearGradientBrush>
  </Setter.Value>
</Setter>


我得到了这个错误:“不能在样式设置器上设置TargetName属性。”另外,如果我将这个代码放在Application.xmal中(它在自己的资源字典中),我会得到这个错误:“属性'TargetName'不代表'Setter'的有效目标,因为找不到名为'MyBackgroundElement'的元素。确保目标在使用它的任何设置器、触发器或条件之前声明。“我认为您需要将样式触发器更改为模板触发器,作为ControlTemplate的一部分。我认为父样式不知道在子模板中创建的元素。当然,
Trigger
s作用于
ControlTemplate
中的元素需要在该模板的范围内定义。谢谢你,史蒂夫!
<Setter Property="Background">
  <Setter.Value>
      <LinearGradientBrush EndPoint="0.5,1" StartPoint="0.5,0">
          <GradientStop Color="#FF5BB75B" Offset="0" />
          <GradientStop Color="#FF449B44" Offset="1" />
      </LinearGradientBrush>
  </Setter.Value>
</Setter>