Summary:
We're seeing ` inputRange must be monotonically increasing -1,0,0,-33,-32 ` which happens when we
have zero height headers, wherever those come from...maybe rendering null?
The math was also off and didn't handle variable height headers correctly, and it was confusing
because it was `setNextHeaderY` with the header y _minus it's height_, which only works
if the prev height was also the same height.
Reviewed By: furdei
Differential Revision: D4649404
fbshipit-source-id: c2c2d438fa0d0b979c2cbdfa5752eaf86c14768b
Summary:
This re-implements sticky headers in JS to make it work on Android.
The only change that was needed was to expose a way to attach a an animated value to an event manually since we can't use the Animated wrapper and `Animated.event` to do it for us because this is implemented directly in the `ScrollView` component. Simply exposed `attachNativeEvent` that takes a ref, event name and event object mapping. This is what is used by `Animated.event`.
TODO:
- Need to check why momentum scrolling isn't triggering scroll events properly on Android.
- Remove native iOS implementation
- cleanup / fix flow
**Test plan**
Test the example list in UIExplorer, test the ListViewPaging example.
Closes https://github.com/facebook/react-native/pull/11315
Differential Revision: D4450278
Pulled By: sahrens
fbshipit-source-id: fec8da2cffce9807d74f8e518ebdefeb6a708667
