Anchor the whole object

We can use AnchorEmpty to fix RealityView in one place, such as a wall. Now I hope that it can not only be fixed in one place, but also fill the whole place with RealityView by stretching. For example: My RealityView is a picture, which is now anchored to the wall, and ARKit will stretch the picture according to the size of the wall. How to achieve the whole wall? Thank you!

Anchor the whole object
 
 
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