Bellwether/HistoryDLL/ThumbnailContainer.xaml

<UserControl x:Class="HistoryDLL.ThumbnailContainer"
             xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
             xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" 
             xmlns:d="http://schemas.microsoft.com/expression/blend/2008" 
             xmlns:local="clr-namespace:HistoryDLL"
             mc:Ignorable="d" >
    <UserControl.Resources>
        <Storyboard x:Key="sbShowStart">
            <DoubleAnimationUsingKeyFrames Storyboard.TargetProperty="(UIElement.Opacity)" Storyboard.TargetName="uxStackPanel">
                <EasingDoubleKeyFrame KeyTime="0:0:0.1" Value="1"/>
            </DoubleAnimationUsingKeyFrames>
        </Storyboard>
        <Storyboard x:Key="sbShowStop">
            <DoubleAnimationUsingKeyFrames Storyboard.TargetProperty="(UIElement.Opacity)" Storyboard.TargetName="uxStackPanel">
                <EasingDoubleKeyFrame KeyTime="0:0:0.1" Value="0"/>
            </DoubleAnimationUsingKeyFrames>
        </Storyboard>
    </UserControl.Resources>
    <StackPanel Name="uxStackPanel" Opacity="0.0" >

    </StackPanel>
</UserControl>