fix: window scrolling in grouped mode

petyosi · Jan 4, 2023 · aa4df5a · aa4df5a
1 parent f249026
commit aa4df5a
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Showing 2 changed files with 15 additions and 1 deletion.
diff --git a/examples/window-group-scroll.tsx b/examples/window-group-scroll.tsx
@@ -0,0 +1,14 @@
+import * as React from 'react'
+import { GroupedVirtuoso } from '../src'
+
+export function Example() {
+  return (
+    <GroupedVirtuoso
+      useWindowScroll
+      groupCounts={Array.from({ length: 20 }).fill(3) as number[]}
+      itemContent={(index) => <div style={{ height: '20px' }}>Item {index}</div>}
+      groupContent={(index) => <div style={{ height: '30px', backgroundColor: 'gray' }}>Group {index}</div>}
+      style={{ height: '300px' }}
+    />
+  )
+}
diff --git a/src/hooks/useChangedChildSizes.ts b/src/hooks/useChangedChildSizes.ts
@@ -20,7 +20,7 @@ export default function useChangedListContentsSizes(
     }
 
     // eslint-disable-next-line @typescript-eslint/no-unsafe-member-access
-    const windowScrolling = (scrollableElement.firstElementChild! as HTMLDivElement).dataset['viewportType']! === 'window'
+    const windowScrolling = (scrollableElement.lastElementChild! as HTMLDivElement).dataset['viewportType']! === 'window'
 
     const scrollTop = customScrollParent
       ? customScrollParent.scrollTop