Scrolling so smooth like the butter on a muffin [How to: Animate the Horizontal/VerticalOffset properties of a ScrollViewer]

re: Scrolling so smooth like the butter on a muffin [How to: Animate the Horizontal/VerticalOffset properties of a ScrollViewer]

Balint Farkas — Wed, 16 May 2012 13:33:13 GMT

Thanks man, this just saved me hours and hours in a SL project.

re: Scrolling so smooth like the butter on a muffin [How to: Animate the Horizontal/VerticalOffset properties of a ScrollViewer]

David Anson — Sat, 13 Aug 2011 05:15:02 GMT

WantsMoreSettlesForLess,

The code you show is a DependencyProperty getter, not a constructor. It will return null until a value is set - which the example XAML does via a Binding/ElementName, but which could be done in code by setting the property.

Hope this helps!

re: Scrolling so smooth like the butter on a muffin [How to: Animate the Horizontal/VerticalOffset properties of a ScrollViewer]

WantsMoreSettlesForLess — Thu, 11 Aug 2011 21:57:07 GMT

If the ScrollViewer was not created in xaml then, when this thing constructs, there is no ScrollViewer.

public ScrollViewer ScrollViewer {

get { return (ScrollViewer)GetValue(ScrollViewerProperty);

returns null since there is no actual scrollviewer control when this runs. FYI.

re: Scrolling so smooth like the butter on a muffin [How to: Animate the Horizontal/VerticalOffset properties of a ScrollViewer]

David Anson — Thu, 13 Aug 2009 08:07:13 GMT

SharpGIS,

Great stuff! Loved the post and thanks very much for following up on this! :)

re: Scrolling so smooth like the butter on a muffin [How to: Animate the Horizontal/VerticalOffset properties of a ScrollViewer]

Morten Nielsen — Wed, 12 Aug 2009 04:32:45 GMT

Inspired by your approach I blogged my ScrollViewer behavior here: http://www.sharpgis.net/post/2009/08/11/Silverlight-Behaviors-Triggers-and-Actions.aspx

I made a few changes to the animation. I only use EaseOut since this gave a better feel to it, and instead of using Grid.Loaded for triggering the storyboard I used the MouseWheel event.

re: Scrolling so smooth like the butter on a muffin [How to: Animate the Horizontal/VerticalOffset properties of a ScrollViewer]

Morten Nielsen — Tue, 11 Aug 2009 21:26:39 GMT

I managed to convert this code to a "real" Blend behavior which cleans up the usage a lot (no need for the ScrollViewerOffsetMediator). I'll try and blog it tonight.

But basically it now looks like this:

<i:Interaction.Behaviors>

<behaviors:MouseScrollViewer />

</i:Interaction.Behaviors>

</ScrollViewer>

re: Scrolling so smooth like the butter on a muffin [How to: Animate the Horizontal/VerticalOffset properties of a ScrollViewer]

David Anson — Wed, 05 Aug 2009 21:07:07 GMT

michaudv,

According to my current understanding of Blend Behaviors, I could not use them to add the writable DependencyProperty that's necessary to get the desired animate-able behavior. If you know otherwise, a pointer to more information would be great!

Either way, that doesn't mean you can't use this solution with Blend! :) Once you've compiled ScrollViewerOffsetMediator into some assembly in your project, you should be able to drop it onto the XAML design surface just like any other element - and then hook it up via the standard Blend mechanisms, and everything should work just fine. Other than the code for ScrollViewerOffsetMediator, my sample is 100% XAML-based - no code required - so the general process should be pretty Blend-friendly.

Hope this helps!

re: Scrolling so smooth like the butter on a muffin [How to: Animate the Horizontal/VerticalOffset properties of a ScrollViewer]

michaudv — Wed, 05 Aug 2009 15:55:28 GMT

Why don't you make a behavior of this? this way peoples working in blend can reuse it. Just an idea