NativeScrollEvent

code:react-native/Libraries/Components/ScrollView/ScrollView.d.ts

export interface NativeScrollEvent {

contentInset: NativeScrollRectangle;

contentOffset: NativeScrollPoint;

contentSize: NativeScrollSize;

layoutMeasurement: NativeScrollSize;

velocity?: NativeScrollVelocity | undefined;

zoomScale: number;

/**

* @platform ios

*/

targetContentOffset?: NativeScrollPoint | undefined;

}

https://gyazo.com/91addc92125f6a0ff5ee5d9858ce002e https://stackoverflow.com/a/53035034

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code:ts

const handleScroll = (e: NativeScrollEvent) => {

if (isCloseToRight(e)(offset)) {...}

if (isCloseToLeft(e)(offset)) {...}

};

const isCloseToRight =

({ layoutMeasurement, contentOffset, contentSize }: NativeScrollEvent) =>

(threshold: number) => {

return (

layoutMeasurement.width + contentOffset.x >=

contentSize.width - threshold

);

};

const isCloseToLeft =

({ contentOffset }: NativeScrollEvent) =>

(threshold: number) => {

return contentOffset.x <= threshold;

};