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silverlightxamlanimationvisualstatemanagerstates

How can I use VisualStates in a ChildWindow?


Is there any way to use the VisualStateManager with my ChildWindow subclass? Calls to VisualStateManager do nothing, and the googling I did implied the only way to achieve this is with manual calls to Storyboards. That's so much sloppier and prone to error. Has anyone found a way to achieve it?

Updated with example code. To use it, just create a new Silverlight Project, and call ExampleWindow.ShowWindow() from a button click on the main page. You'll see the button, even though the constructor sets the state that should hide the button.

XAML (ExampleWindow.xaml):

<controls:ChildWindow
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:controls="clr-namespace:System.Windows.Controls;assembly=System.Windows.Controls"
    xmlns:d="http://schemas.microsoft.com/expression/blend/2008" xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
    mc:Ignorable="d"
    xmlns:ic="clr-namespace:Microsoft.Expression.Interactivity.Core;assembly=Microsoft.Expression.Interactions"
    x:Class="Client.Windows.ExampleWindow"
    Title="Example">
    <Grid x:Name="LayoutRoot">
        <VisualStateManager.VisualStateGroups>
            <VisualStateGroup x:Name="ExampleStateGroup">
                <VisualState x:Name="ExampleBaseState">
                    <Storyboard>
                        <DoubleAnimationUsingKeyFrames BeginTime="00:00:00" Duration="00:00:00.0010000" Storyboard.TargetName="button" Storyboard.TargetProperty="(UIElement.Opacity)">
                            <EasingDoubleKeyFrame KeyTime="00:00:00" Value="0"/>
                        </DoubleAnimationUsingKeyFrames>
                    </Storyboard>
                </VisualState>
            </VisualStateGroup>
        </VisualStateManager.VisualStateGroups>
        <VisualStateManager.CustomVisualStateManager>
            <ic:ExtendedVisualStateManager/>
        </VisualStateManager.CustomVisualStateManager>
        <Button x:Name="button" Content="You Shouldn't See Me" Grid.ColumnSpan="2" Width="150" Height="150" HorizontalAlignment="Center" VerticalAlignment="Center"/>
    </Grid>
</controls:ChildWindow>

Code Behind (ExampleWindow.xaml.cs):

using System.Windows;
using System.Windows.Controls;

namespace Client.Windows
{
    public partial class ExampleWindow : ChildWindow
    {
        public ExampleWindow()
        {
            InitializeComponent();

            VisualStateManager.GoToState( this, "ExampleBaseState", true );
        }

        public static void ShowWindow()
        {
            var w = new ExampleWindow();
            w.Show();
        }
    }
}

Solution

  • So far, the only workaround I've found is to put anything that requires visual states into a UserControl. The UserControl can have states, and successfully switch between them, and communicate anything necessary to the ChildWindow through events, methods, and properties.