Bug report.
(Check the step you've followed - put an x character between the square brackets ([]).)
Yes, it is an explicit react-native-snap-carousel bug
It is reproducible in Snack on iOS, iOS 12.2
Yes
Environment:
React: 16.8.3
React native: 0.59.2
react-native-snap-carousel: 3.8.0
Target Platform:
iOS (12.2)
While snapping between items, the active item would appear bigger.
While using
onScroll={Animated.event([{
nativeEvent: { contentOffset: { x: scrollValue.current } },
}])}
with Animated in order to interpolate colors for custom indicator
and also onSnapToItem with hooks calls inside, the snapped item where hooks were called become permanently inactive in terms of bigger display.
Removing onScroll or hooks from onSnapToItem fixes the issue, but I need both methods.

(Paste the link to a Snack example in which the issue can be reproduced. Please follow the guidelines for providing a Minimal, Complete, and Verifiable example.)
(Write your steps so that anyone can reproduce the issue in the Snack demo you provided.)
I have the same issue with two items. When the first item is swiped by me, the interpolator won't work on any other swipe actions. I have downgraded a version to 3.7.5 and it works perfectly after that.
Same issue for me on Android 6
I confirm that using am useState hook inside onSnapToItem cause bug on carousel .
const [carouselIndex, setIndex] = React.useState(initialIndex);
const handleIndexChange = (index: number) => {
setIndex(index);
};
<Carousel
data={productList}
ref={refCarousel}
style={fillContainer}
sliderWidth={width}
itemWidth={width}
firstItem={initialIndex}
onBeforeSnapToItem={handleIndexChange}
keyboardShouldPersistTaps="always"
renderItem={({ item, index }) => {
return (
<InventoryProductSheet
key={item.id}
productId={item.id}
index={index}
isFocused={index === carouselIndex}
/>
);
}}
/>
Most helpful comment
I have the same issue with two items. When the first item is swiped by me, the interpolator won't work on any other swipe actions. I have downgraded a version to 3.7.5 and it works perfectly after that.