Question

我正在为WPF TabControl TabItem定义一个样式。我想要显示一个轻微的＆＃34;推下来＆＃34;当按下鼠标（左键）并且未选择TabItem但我找不到TabItem时对Trigger的效果。

我尝试定义MultiTrigger IsMouseLeftButtonDown和IsPressed属性，但都没有被识别。

<Style TargetType="{x:Type TabItem}">
      <Setter Property="Template">
            <Setter.Value>
                  <ControlTemplate TargetType="TabItem">
                        <Border Name="bd" BorderThickness="1,1,0,0">
                            <Grid>
                                <ContentPresenter VerticalAlignment="Center" HorizontalAlignment="Center"
                                                  ContentSource="Header"/>    
                            </Grid>
                        </Border>
                        <ControlTemplate.Triggers>
                            <MultiTrigger>
                                <MultiTrigger.Conditions>
                                    <Condition Property="IsMouseLeftButtonDown" Value="True" /> <!--NOT RECOGNIZED-->
                                    <Condition Property="IsSelected" Value="False" />
                                </MultiTrigger.Conditions>
                                <Setter TargetName="bd" Property="Background" >
                                    <Setter.Value>
                                         <LinearGradientBrush EndPoint="0.5,1" StartPoint="0.5,0">
                                              <GradientStop Color="Green" Offset="0"/>
                                              <GradientStop Color="Yellow" Offset="1"/>
                                         </LinearGradientBrush>
                                    </Setter.Value>
                                 </Setter>
                            </MultiTrigger>
                       </ControlTemplate.Triggers>
                 </ControlTemplate>
            </Setter.Value>
       </Setter>
 </Style>

如何在Trigger上按下鼠标左键时设置一个TabItem？

修改

我试过了EventTrigger，但我看不到下面的效果

<EventTrigger RoutedEvent="UIElement.PreviewMouseLeftButtonDown">
     <BeginStoryboard>
           <Storyboard>
               <ColorAnimation Storyboard.TargetProperty="(Border.Background).(SolidColorBrush.Color)" To="Green" Duration="0:0:3" />
           </Storyboard>
     <BeginStoryboard/>
<EventTrigger/>

可以用这种方式实现吗？

Answer 1

此示例向您展示了如何使用EventTriggers。

注意

您可能必须在那些Triggers中完全设置突出显示逻辑，因为每次都会覆盖值Trigger。

<EventTrigger RoutedEvent="PreviewMouseDown" > <EventTrigger.Actions> <BeginStoryboard> <Storyboard > <ObjectAnimationUsingKeyFrames Storyboard.TargetName="bd" Storyboard.TargetProperty="Background" Duration="0:0:3" BeginTime="0" AutoReverse="True"> <ObjectAnimationUsingKeyFrames.KeyFrames> <DiscreteObjectKeyFrame KeyTime="0:0:0" Value="{x:Static Brushes.Green}" /> </ObjectAnimationUsingKeyFrames.KeyFrames> </ObjectAnimationUsingKeyFrames> </Storyboard> </BeginStoryboard> </EventTrigger.Actions> </EventTrigger> <EventTrigger RoutedEvent="PreviewMouseUp" > <EventTrigger.Actions> <BeginStoryboard> <Storyboard > <ObjectAnimationUsingKeyFrames Storyboard.TargetName="bd" Storyboard.TargetProperty="Background" Duration="0:0:3" BeginTime="0" AutoReverse="True"> <ObjectAnimationUsingKeyFrames.KeyFrames> <DiscreteObjectKeyFrame KeyTime="0:0:0" Value="{x:Static Brushes.Transparent}" /> </ObjectAnimationUsingKeyFrames.KeyFrames> </ObjectAnimationUsingKeyFrames> </Storyboard> </BeginStoryboard> </EventTrigger.Actions> </EventTrigger>

鼠标左键按下时WPF TabItem样式

1 个答案: