WPF: how to send RoutedEvent to be triggered inside a DataTemplate ?

christoph brandle

Many people have seen the flipping panel by Ian Griffiths as shown by Sacha Barber on this MyFriends sample on CP. http://www.interact-sw.co.uk/iangblog/2007/05/17/wpf-flippable-3D-list http://www.codeproject.com/KB/WPF/MyFriends.aspx I try now to figure out, how to invoke the trigger to flip the page by a RoutedEvent, but I cannot get it there.

    public void ShowBack()
    {
        DataTemplate \_dt = (DataTemplate)this.FindResource("flipItemTemplate");
        RaiseEvent(new RoutedEventArgs(FlipToBackEvent, \_dt.VisualTree));
    }

should call this one:

        <DataTemplate x:Key="flipItemTemplate">
            <Grid Width="270" Height="270">
                <Viewport3D Grid.Column="0" x:Name="vp3D" Visibility="Hidden">
                </Viewport3D>

                <Border x:Name="frontWrapper">
                    <Border x:Name="frontHost" Background="Transparent">
                        <Border.Triggers>
                            <EventTrigger RoutedEvent="local:UserControl1.FlipToBackEvent">
                                <BeginStoryboard>
                                </BeginStoryboard>
                            </EventTrigger>
                        </Border.Triggers>
                        <ContentPresenter  Content="{Binding}" ContentTemplate="{StaticResource frontTemplate}" />
                    </Border>
                </Border>}

Does anyone know how I can invoke from Codebehind the Storyboard inside the Trigger, inside the DataTemplate? Tips on this are welcome :) Christoph

Sacha Barber

Christoph Not sure what you are trying to do with the VisualTree as part of the FlipToBackEvent, but I would have thought you don't need to do that, and just raise the FlipToBackEvent event when you need to and them XAML Trigger will see that, and act accordingly. This would seem right to me, but I just don't have the time right now to look further, sorry.

Sacha Barber

Microsoft Visual C# MVP 2008
Codeproject MVP 2008

Your best friend is you. I'm my best friend too. We share the same views, and hardly ever argue My Blog : sachabarber.net

christoph brandle

Sacha Just fire was my first attempt, and works for Triggers that are not inside a DataTemplate, so I tried different things.. they all don't work :( Thanks anyway

Sacha Barber

Ah ok, sorry to hear that. It sounded like that would work. Sorry I don't have more time to look at this myself.

Sacha Barber

Microsoft Visual C# MVP 2008
Codeproject MVP 2008

Your best friend is you. I'm my best friend too. We share the same views, and hardly ever argue My Blog : sachabarber.net

christoph brandle

Sacha - found it finally (I rarely give up) this one was hard for me, then I came to this // http://social.msdn.microsoft.com/Forums/en-US/wpf/thread/4a04938b-690b-4bd0-969a-6dc4f6d6fda5/ this.displayContent = ContentControl

        foreach (Border \_border in FindInVisualTree(this.displayContent, a => { return a is Border; }))
        {
            \_border.RaiseEvent(new RoutedEventArgs(FlipToLoginEvent));
        }

- Christoph

Sacha Barber

Cool, glad you are now sorted. I would have maybe gone for the x:Key idea on that thread.

Sacha Barber

Microsoft Visual C# MVP 2008
Codeproject MVP 2008

Your best friend is you. I'm my best friend too. We share the same views, and hardly ever argue My Blog : sachabarber.net

christoph brandle

you are right, not perfect though working here I present my final solution (for the ones that search the internet desperately :)

    //  http://www.beacosta.com/blog/?p=41
    private T GetObjectOfTypeInVisualTree<T>(DependencyObject dpob) where T : DependencyObject
    {
        int count = VisualTreeHelper.GetChildrenCount(dpob);
        for (int i = 0; i < count; i++)
        {
            DependencyObject child = VisualTreeHelper.GetChild(dpob, i);
            T childAsT = child as T;
            if (childAsT != null)
            {
                return childAsT;
            }
            childAsT = GetObjectOfTypeInVisualTree<T>(child);
            if (childAsT != null)
            {
                return childAsT;
            }
        }
        return null;
    }

    private void ManualStartAnimation(string templateName, string elementName, RoutedEventArgs eventArgs)
    {
        //  this works too
        //  http://social.msdn.microsoft.com/Forums/en-US/wpf/thread/4a04938b-690b-4bd0-969a-6dc4f6d6fda5/

        //  this is implemented
        //  http://joshsmithonwpf.wordpress.com/2007/06/28/how-to-use-findname-with-a-contentcontrol/
        //  together with this (GetObjectOfTypeInVisualTree)
        //  http://www.beacosta.com/blog/?p=41

        DataTemplate   \_dt = (DataTemplate)this.FindResource(templateName);
        if (\_dt != null)
        {
           //  reminder: displayContent is the ContentControl
            ContentPresenter \_cp = GetObjectOfTypeInVisualTree<ContentPresenter>(this.displayContent);
            if (\_cp != null)
            {
                UIElement \_element = (UIElement)\_dt.FindName(elementName, \_cp);
                if (\_element != null)
                {
                    \_element.RaiseEvent(eventArgs);
                }
            }
        }
    }

    public void ShowLogin()
    {

->kick ManualStartAnimation("flipItemTemplate", "frontHost", new RoutedEventArgs(FlipToLoginEvent));
}

jp chow

THANK YOU! I so did desperately search the internet and I found your nice solution. Thanks again! :laugh:

modified on Friday, January 9, 2009 3:19 PM