Positional Lag in Nested UIBlock Hierarchy

[justinmajetich]

I'm dealing with "lag" in the movement of a UIBlock hierarchy beneath but not included in a parent UIBlock hierarchy. The issue is documented in a video linked below.

Here is the structure of an item which is the direct child of a scrollable GridView. The AssetPreview GameObject intentionally creates a gap in the UIBlock hierarchy. A second UIBlock hierarchy begins with PreviewClipMask - the position second hierarchy visibly lags when the overall AssetLibraryItem2D is moved via Scroller. Here's a visual explanation:

My thought was this "lag" must be the result of the Transform position and UIBlock.Position being out of sync at the end of a frame in which the menu item has moved. Something like, both ItemView and PreviewClipMask's UIBlock positions are calculated and set at the end of a given frame; however, this updated position isn't reflected in PreviewClipMask's Transform until the next frame. I haven't completely wrapped my head around it, but that's my general impression of what's happening. So, I tested a forceful solution, setting the UIBlock.Position manually on Update for the UIBlock attached to PreviewClipMask:

The result really confuses me. Positional lag for items belonging to the two outer columns of the GridView is resolved; however, lag persists for items of the center column.

Both the initial issue and the partial fix are demonstrated in this video: https://youtu.be/48acEJW1cOI

I can understand how a lag in accurate position setting could be expected behavior for my given hierarchy of UIBlocks. That being said, if anyone has a better solution than what I've outlined above, please do share. However, what I really can't understand is why the hack I've implemented only fixes my issue for items withing certain parts of the GridView. Thanks in advance for any help!

[adgray1]

We believe this to be a bug on our end, so I'm moving it over to "Bugs" while we investigate.

Thank you for bringing this to our attention and for the details/videos to help us clearly understand the issue you're experiencing!