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Animation during SelectionChanged

I have TabControlwhere each TabItemhas a separate control as an element Content. Now I can easily complete the storyboard when switching to a tab using UserControl.LoadedEventTrigger. However, I also want to start the exit animation when switching from one tab to another (i.e., allow the old content control to be animated, and then the new content control entry animation).

Can this be done with standard WPF constructs?

If not, how do I get started developing a custom solution that handles this?

Edit: I went ahead and made a modified TabControl that extends the TabControl base and overrides its method OnSelectionChangedas follows:

protected override void OnSelectionChanged(SelectionChangedEventArgs e)
{
    if (e.AddedItems.Count == 1 && e.RemovedItems.Count == 1)
    {
        var oldTab = e.RemovedItems[0] as TabItem;

        if (oldTab != null)
        {
            var exitStoryboard = /** code to find the storyboard **/
            if (exitStoryboard != null)
            {
                exitStoryboard.Completed = (_, __) => base.OnSelectionChanged(e);
                exitStoryboard.Begin();
                return;
            }
        }
    }
    base.OnSelectionChanged(e);
}

, , , base.OnSelectionChanged , -, , . ?

+5
3

2 , , , .

, VisualBrush , "" , .

<Grid xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
   <TabControl>
      <TabItem x:Name="tab1" Header="Tab 1">
         <Border Background="Transparent">
            <Grid>
               <TextBlock FontSize="40" Foreground="Red" Text="Tab 1 Contents">
                  <TextBlock.Triggers>
                     <EventTrigger RoutedEvent="Loaded">
                        <BeginStoryboard>
                           <Storyboard>
                              <DoubleAnimationUsingKeyFrames Storyboard.TargetProperty="Opacity">
                                 <DiscreteDoubleKeyFrame KeyTime="0:0:0" Value="0.0"/>
                              </DoubleAnimationUsingKeyFrames>
                              <DoubleAnimation
                                 Duration="0:0:0.25"
                                 From="1"
                                 Storyboard.TargetName="tab2Shadow"
                                 Storyboard.TargetProperty="Opacity"
                                 To="0"/>
                              <DoubleAnimation
                                 BeginTime="0:0:0.25"
                                 Duration="0:0:0.25"
                                 From="0"
                                 Storyboard.TargetProperty="Opacity"
                                 To="1"/>
                           </Storyboard>
                        </BeginStoryboard>
                     </EventTrigger>
                  </TextBlock.Triggers>
               </TextBlock>
               <Rectangle x:Name="tab2Shadow">
                  <Rectangle.Fill>
                     <VisualBrush
                        AlignmentX="Left"
                        AlignmentY="Top"
                        AutoLayoutContent="False"
                        Stretch="None"
                        Visual="{Binding ElementName=tab2, Path=Content}"/>
                  </Rectangle.Fill>
               </Rectangle>
            </Grid>
         </Border>
      </TabItem>
      <TabItem x:Name="tab2" Header="Tab 2">
         <Border Background="Transparent">
            <Grid>
               <TextBlock FontSize="40" Foreground="Red" Text="Tab 2 Contents">
                  <TextBlock.Triggers>
                     <EventTrigger RoutedEvent="Loaded">
                        <BeginStoryboard>
                           <Storyboard>
                              <DoubleAnimationUsingKeyFrames Storyboard.TargetProperty="Opacity">
                                 <DiscreteDoubleKeyFrame KeyTime="0:0:0" Value="0.0"/>
                              </DoubleAnimationUsingKeyFrames>
                              <DoubleAnimation
                                 Duration="0:0:0.25"
                                 From="1"
                                 Storyboard.TargetName="tab1Shadow"
                                 Storyboard.TargetProperty="Opacity"
                                 To="0"/>
                              <DoubleAnimation
                                 BeginTime="0:0:0.25"
                                 Duration="0:0:0.25"
                                 From="0"
                                 Storyboard.TargetProperty="Opacity"
                                 To="1"/>
                           </Storyboard>
                        </BeginStoryboard>
                     </EventTrigger>
                  </TextBlock.Triggers>
               </TextBlock>
               <Rectangle x:Name="tab1Shadow">
                  <Rectangle.Fill>
                     <VisualBrush
                        AlignmentX="Left"
                        AlignmentY="Top"
                        AutoLayoutContent="False"
                        Stretch="None"
                        Visual="{Binding ElementName=tab1, Path=Content}"/>
                  </Rectangle.Fill>
               </Rectangle>
            </Grid>
         </Border>
      </TabItem>
   </TabControl>
</Grid>
+1

TabControl.SelectionChanged.

0

tabcontrol Selector.SelectionChanged RoutedEvent

        <Style x:Key="{x:Type TabControl}"
           TargetType="TabControl">
        <Setter Property="VerticalContentAlignment" Value="Stretch" />
        <Setter Property="Template">
            <Setter.Value>
                <ControlTemplate TargetType="TabControl">
                    <Grid>
                        <Grid.RowDefinitions>
                            <RowDefinition Height="Auto" />
                            <RowDefinition Height="40" />
                            <RowDefinition />
                        </Grid.RowDefinitions>

                        <UniformGrid Grid.Row="0"
                                     Rows="1"
                                     IsItemsHost="True" />
                        <ContentPresenter x:Name="TabContent"
                                          Grid.Row="2"
                                          Content="{TemplateBinding SelectedContent}">

                        </ContentPresenter>
                    </Grid>

                    <ControlTemplate.Triggers>
                        <EventTrigger RoutedEvent="Selector.SelectionChanged">
                            <BeginStoryboard>
                                <Storyboard>
                                    <DoubleAnimation From="0"
                                                     To="1"
                                                     Storyboard.TargetProperty="Opacity"
                                                     Storyboard.TargetName="TabContent"
                                                     Duration="0:0:0.5" />
                                </Storyboard>
                            </BeginStoryboard>
                        </EventTrigger>
                    </ControlTemplate.Triggers>
                </ControlTemplate>
            </Setter.Value>
        </Setter>
    </Style>
0

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