Visual of a UIElement is not sized?

[JustinXinLiu]

What I've noticed is the following piece of code will always return a Size of (0,0) for any UIElement.

var visual = ElementCompositionPreview.GetElementVisual(MyUIElement);
Debug.WriteLine($"Visual's size: {visual.Size}");

Output

Visual's size: <0, 0>

Is this by design? I wonder what if I want to animate the Size of the element using Composition Animations?

[sernaj]

The preview API ElementCompositionPreview.GetElementVisual() currently returns a Visual with a size of 0,0 by design. Our recommendation is to use transforms instead of size animations where possible since transforms can be independently animated to provide a smooth visual experience. As with XAML Storyboards, the size of XAML elements can’t be animated independently because it’s dependent on XAML layout and potentially app code running on the UI thread. We are looking at options in the future to expand interop between XAML and composition APIs in this area.

[JustinXinLiu]

Thanks @sernaj . Just want to clarify, the transforms you mentioned are Visual properties like Rotation, Scale, Offset, etc. Right?

[sernaj]

Correct.

[JustinXinLiu]

Thanks for the clarification.