TabItem旋转WPF

Question

我在WPF中是新的，我试图通过使用样式在选项卡控件中的选择和取消选择选项卡项上创建动画。

不幸的是，它不工作，我不知道为什么。这种风格有什么问题：

<Style TargetType="{x:Type TabItem}" x:Key="MainTabControlItems">
        <Style.Setters>
            <Setter Property="HorizontalAlignment" Value="Stretch"></Setter>
            <Setter Property="Margin" Value="2"></Setter>
            <Setter Property="VerticalAlignment" Value="Stretch"></Setter>
            <Setter Property="BorderThickness" Value="2"></Setter>
        </Style.Setters>
        <Style.Triggers>
            <Trigger Property="IsSelected" Value="true">
                <Setter Property="FontWeight" Value="Bold" />

                <Trigger.EnterActions>
                    <BeginStoryboard>
                        <Storyboard>
                            <DoubleAnimation Storyboard.TargetProperty="(TabItem.RenderTransform).(RotateTransform.Angle)" 
                                             To="30" Duration="0:0:5"/>
                        </Storyboard>
                    </BeginStoryboard>
                </Trigger.EnterActions>
            </Trigger>
            <Trigger Property="IsSelected" Value="false">
                <Setter Property="FontWeight" Value="Normal" />

                <Trigger.EnterActions>
                    <BeginStoryboard>
                        <Storyboard>
                            <DoubleAnimation Storyboard.TargetProperty="(TabItem.RenderTransform).(RotateTransform.Angle)" To="-30" Duration="0:0:5"/>
                        </Storyboard>
                    </BeginStoryboard>
                </Trigger.EnterActions>
            </Trigger>           
        </Style.Triggers>
    </Style>

<TabControl Name="tcAplabet"
                    SizeChanged="tcAplabet_SizeChanged" SelectionChanged="tcAplabet_SelectionChanged"
                    Grid.Column="0"
                    Grid.Row="0"
                    TabStripPlacement="Left"
                    ItemContainerStyle="{DynamicResource ResourceKey=MainTabControlItems}">

            <TabItem Header="A"  IsSelected="True" Style="{DynamicResource ResourceKey=MainTabControlItems}" />
            <TabItem Header="B" Style="{DynamicResource ResourceKey=MainTabControlItems}" />
            <TabItem Header="C" Style="{DynamicResource ResourceKey=MainTabControlItems}" />
            <TabItem Header="D" Style="{DynamicResource ResourceKey=MainTabControlItems}" />
            <TabItem Header="E" Style="{DynamicResource ResourceKey=MainTabControlItems}" />
            <TabItem Header="F" Style="{DynamicResource ResourceKey=MainTabControlItems}" />
            <TabItem Header="G" Style="{DynamicResource ResourceKey=MainTabControlItems}" />
            <TabItem Header="H" Style="{DynamicResource ResourceKey=MainTabControlItems}" />
            <TabItem Header="CH" Style="{DynamicResource ResourceKey=MainTabControlItems}" />
            <TabItem Header="I" Style="{DynamicResource ResourceKey=MainTabControlItems}" />
            <TabItem Header="J" Style="{DynamicResource ResourceKey=MainTabControlItems}" />
            <TabItem Header="K" Style="{DynamicResource ResourceKey=MainTabControlItems}" />
            <TabItem Header="L" Style="{DynamicResource ResourceKey=MainTabControlItems}" />
            <TabItem Header="M" Style="{DynamicResource ResourceKey=MainTabControlItems}" />
            <TabItem Header="N" Style="{DynamicResource ResourceKey=MainTabControlItems}" />
            <TabItem Header="O" Style="{DynamicResource ResourceKey=MainTabControlItems}" />
            <TabItem Header="P" Style="{DynamicResource ResourceKey=MainTabControlItems}" />
            <TabItem Header="Q" Style="{DynamicResource ResourceKey=MainTabControlItems}" />
            <TabItem Header="R" Style="{DynamicResource ResourceKey=MainTabControlItems}" />
            <TabItem Header="S" Style="{DynamicResource ResourceKey=MainTabControlItems}" />
            <TabItem Header="T" Style="{DynamicResource ResourceKey=MainTabControlItems}" />
            <TabItem Header="U" Style="{DynamicResource ResourceKey=MainTabControlItems}" />
            <TabItem Header="V" Style="{DynamicResource ResourceKey=MainTabControlItems}" />
            <TabItem Header="W" Style="{DynamicResource ResourceKey=MainTabControlItems}" />
            <TabItem Header="X" Style="{DynamicResource ResourceKey=MainTabControlItems}" />
            <TabItem Header="Y" Style="{DynamicResource ResourceKey=MainTabControlItems}" />
            <TabItem Header="Z" Style="{DynamicResource ResourceKey=MainTabControlItems}" />

            <TabControl.ContentTemplate>
                <DataTemplate>
                    <controls:MainTabContent Name="cMainTabContent" Margin="2"></controls:MainTabContent>
                </DataTemplate>
            </TabControl.ContentTemplate>

        </TabControl>

谢谢你的建议..。

Answer 1

问题-- RenderTransform的一个实例--不是为您的TabItem创建的。它在空对象上应用动画，并吞咽由此产生的任何异常。

把这个添加到你的风格中：

 <Setter Property="RenderTransform">
     <Setter.Value>
         <TransformGroup>
             <RotateTransform />
             <TranslateTransform />
             <SkewTransform />
             <ScaleTransform />                                
         </TransformGroup>
      </Setter.Value>
  </Setter>
  <Setter Property="RenderTransformOrigin" Value="0.5,0.5"/>

*此外，您可能希望将RenderTransformOrigin设置在表的中心，因为它的左上角不旋转。(除非这是你们男人不想做的)