Ignore bogus onScroll values (#5499)

bluesky-social · Sep 27, 2024 · 4553e6b · 4553e6b
1 parent dd2fedb
commit 4553e6b
Showing 1 changed file with 10 additions and 3 deletions.
diff --git a/src/view/com/pager/PagerWithHeader.tsx b/src/view/com/pager/PagerWithHeader.tsx
@@ -161,10 +161,17 @@ export const PagerWithHeader = React.forwardRef<PagerRef, PagerWithHeaderProps>(
       (e: NativeScrollEvent) => {
         'worklet'
         const nextScrollY = e.contentOffset.y
-        scrollY.value = nextScrollY
-        runOnJS(queueThrottledOnScroll)()
+        // HACK: onScroll is reporting some strange values on load (negative header height).
+        // Highly improbable that you'd be overscrolled by over 400px -
+        // in fact, I actually can't do it, so let's just ignore those. -sfn
+        const isPossiblyInvalid =
+          headerHeight > 0 && Math.round(nextScrollY * 2) / 2 === -headerHeight
+        if (!isPossiblyInvalid) {
+          scrollY.value = nextScrollY
+          runOnJS(queueThrottledOnScroll)()
+        }
       },
-      [scrollY, queueThrottledOnScroll],
+      [scrollY, queueThrottledOnScroll, headerHeight],
     )
 
     const onPageSelectedInner = React.useCallback(