CollectionView virtual (infinite) scrolling - how many items to download and add initially?

[paratype-fonts]

When initially populating CollectionView items, I need to know when a new item becomes not shown (clipped) to stop fetching.

The Scrolled event has very useful properties: LastVisibleItemIndex and FirstVisibleItemIndex, but the number of items to fetch needs to be determined before scroll occurs. I could not find anything functionally similar on the CollectionView itself.

Any suggestions? Thanks!

[dimustriz]

As a workaround, you can override MeasureOverride and match height (and width if needed) with DesiredSize props.