How can I share a VisualStateManager between two (or more) XAML files?

问题

We're writing a Prism based Silverlight application and we've got a whole bunch of pages in separate modules.

The transition between the pages is handled via navigation events and each module has the following methods implemented to show the page when navigated to and hide it when navigated from:

public void Show()
{
    VisualStateManager.GoToState(this, "ShowState", true);
}

public void Hide()
{
    VisualStateManager.GoToState(this, "HideState", true);
}

At the moment "ShowState" and "HideState" are defined in each module's XAML file so are duplicated far too many times.

<Grid x:Name="LayoutRoot">
    <VisualStateManager.VisualStateGroups>
        <VisualStateGroup x:Name="VisualStates">
            <VisualState x:Name="ShowState">
                ...
            </VisualState>
            <VisualState x:Name="HideState">
                ...
            </VisualState>
        </VisualStateGroup>
    </VisualStateManager.VisualStateGroups>

Where ... represents the Storyboard for each transition.

I've just spotted an error in the Storyboard definitions and at the moment I'm going to have to replicate the fix across all the files. It would be better if there was only one definition of the Storyboard which could be referenced in each file.

I've searched all morning for the right syntax but have had no luck what so ever.

How can I share this VisualStateManager between all our XAML files?

回答1:

<Storyboard x:Key="ShowStoryboard">
    <DoubleAnimationUsingKeyFrames BeginTime="00:00:00" Storyboard.TargetName="glow" Storyboard.TargetProperty="(UIElement.Opacity)">
        <SplineDoubleKeyFrame KeyTime="00:00:00.3000000" Value="0"/>
    </DoubleAnimationUsingKeyFrames>
</Storyboard>

<VisualState x:Name="ShowState">
    <BeginStoryboard Storyboard="{StaticResource ShowStoryboard}"/>
</VisualState>

Referencing your Storyboard within XAML can be done as seen above. With the top most portion being a Storyboard stored as a Resource somewhere. After that you should be able to use the BeginStoryboard reference within your VisualState.

EDIT: The above appears possible within WPF however it is not possible in SL. As of current it does not appear the abilty to reuse a Storyboard or VisualState is possible in SL. You should still be able to achieve what you are trying to do by encapsulating the VisualStateManager behavior within a style applied to a custom control. This would provide you the single point of failure you are looking for.

来源：https://stackoverflow.com/questions/4367332/how-can-i-share-a-visualstatemanager-between-two-or-more-xaml-files

标签

silverlight

resources

visualstatemanager