Remove measure items and cleanup BaseInvertedFlatList

src/components/InvertedFlatList/BaseInvertedFlatList.js

@@ -1,9 +1,6 @@
 import PropTypes from 'prop-types';
-import React, {forwardRef, useCallback, useRef} from 'react';
-import {FlatList as NativeFlatlist, View} from 'react-native';
-import _ from 'underscore';
+import React, {forwardRef} from 'react';
 import FlatList from '@components/FlatList';
-import * as CollectionUtils from '@libs/CollectionUtils';
 
 const AUTOSCROLL_TO_TOP_THRESHOLD = 128;
 
@@ -14,148 +11,28 @@ const propTypes = {
 
     /** Same as FlatList although we wrap it in a measuring helper before passing to the actual FlatList component */
     renderItem: PropTypes.func.isRequired,
-
-    /** This must be set to the minimum size of one of the renderItem rows. Web experiences issues when inaccurate. */
-    initialRowHeight: PropTypes.number.isRequired,
-
-    /** Passed via forwardRef so we can access the FlatList ref */
-    innerRef: PropTypes.oneOfType([PropTypes.func, PropTypes.shape({current: PropTypes.instanceOf(NativeFlatlist)})]).isRequired,
-
-    /** Should we measure these items and call getItemLayout? */
-    shouldMeasureItems: PropTypes.bool,
 };
 
 const defaultProps = {
     data: [],
-    shouldMeasureItems: false,
 };
 
-function BaseInvertedFlatList(props) {
-    const {initialRowHeight, shouldMeasureItems, innerRef, renderItem} = props;
-
-    // Stores each item's computed height after it renders
-    // once and is then referenced for the life of this component.
-    // This is essential to getting FlatList inverted to work on web
-    // and also enables more predictable scrolling on native platforms.
-    const sizeMap = useRef({});
-
-    /**
-     * Return default or previously cached height for
-     * a renderItem row
-     *
-     * @param {*} data
-     * @param {Number} index
-     *
-     * @return {Object}
-     */
-    const getItemLayout = (data, index) => {
-        const size = sizeMap.current[index];
-
-        if (size) {
-            return {
-                length: size.length,
-                offset: size.offset,
-                index,
-            };
-        }
-
-        // If we don't have a size yet means we haven't measured this
-        // item yet. However, we can still calculate the offset by looking
-        // at the last size we have recorded (if any)
-        const lastMeasuredItem = CollectionUtils.lastItem(sizeMap.current);
-
-        return {
-            // We haven't measured this so we must return the minimum row height
-            length: initialRowHeight,
-
-            // Offset will either be based on the lastMeasuredItem or the index +
-            // initialRowHeight since we can only assume that all previous items
-            // have not yet been measured
-            offset: _.isUndefined(lastMeasuredItem) ? initialRowHeight * index : lastMeasuredItem.offset + initialRowHeight,
-            index,
-        };
-    };
-
-    /**
-     * Measure item and cache the returned length (a.k.a. height)
-     *
-     * @param {React.NativeSyntheticEvent} nativeEvent
-     * @param {Number} index
-     */
-    const measureItemLayout = useCallback((nativeEvent, index) => {
-        const computedHeight = nativeEvent.layout.height;
-
-        // We've already measured this item so we don't need to
-        // measure it again.
-        if (sizeMap.current[index]) {
-            return;
-        }
-
-        const previousItem = sizeMap.current[index - 1] || {};
-
-        // If there is no previousItem this can mean we haven't yet measured
-        // the previous item or that we are at index 0 and there is no previousItem
-        const previousLength = previousItem.length || 0;
-        const previousOffset = previousItem.offset || 0;
-        sizeMap.current[index] = {
-            length: computedHeight,
-            offset: previousLength + previousOffset,
-        };
-    }, []);
-
-    /**
-     * Render item method wraps the prop renderItem to render in a
-     * View component so we can attach an onLayout handler and
-     * measure it when it renders.
-     *
-     * @param {Object} params
-     * @param {Object} params.item
-     * @param {Number} params.index
-     *
-     * @return {React.Component}
-     */
-    const renderItemFromProp = useCallback(
-        ({item, index}) => {
-            if (shouldMeasureItems) {
-                return <View onLayout={({nativeEvent}) => measureItemLayout(nativeEvent, index)}>{renderItem({item, index})}</View>;
-            }
-
-            return renderItem({item, index});
-        },
-        [shouldMeasureItems, measureItemLayout, renderItem],
-    );
-
-    return (
-        <FlatList
-            // eslint-disable-next-line react/jsx-props-no-spreading
-            {...props}
-            ref={innerRef}
-            renderItem={renderItemFromProp}
-            // Native platforms do not need to measure items and work fine without this.
-            // Web requires that items be measured or else crazy things happen when scrolling.
-            getItemLayout={shouldMeasureItems ? getItemLayout : undefined}
-            windowSize={15}
-            maintainVisibleContentPosition={{
-                minIndexForVisible: 0,
-                autoscrollToTopThreshold: AUTOSCROLL_TO_TOP_THRESHOLD,
-            }}
-            inverted
-        />
-    );
-}
-
-BaseInvertedFlatList.propTypes = propTypes;
-BaseInvertedFlatList.defaultProps = defaultProps;
-BaseInvertedFlatList.displayName = 'BaseInvertedFlatList';
-
-const BaseInvertedFlatListWithRef = forwardRef((props, ref) => (
-    <BaseInvertedFlatList
+const BaseInvertedFlatList = forwardRef((props, ref) => (
+    <FlatList
         // eslint-disable-next-line react/jsx-props-no-spreading
         {...props}
-        innerRef={ref}
+        ref={ref}
+        windowSize={15}
+        maintainVisibleContentPosition={{
+            minIndexForVisible: 0,
+            autoscrollToTopThreshold: AUTOSCROLL_TO_TOP_THRESHOLD,
+        }}
+        inverted
     />
 ));
 
-BaseInvertedFlatListWithRef.displayName = 'BaseInvertedFlatListWithRef';
+BaseInvertedFlatList.propTypes = propTypes;
+BaseInvertedFlatList.defaultProps = defaultProps;
+BaseInvertedFlatList.displayName = 'BaseInvertedFlatList';
 
-export default BaseInvertedFlatListWithRef;
+export default BaseInvertedFlatList;

src/components/InvertedFlatList/index.js

@@ -106,7 +106,6 @@ function InvertedFlatList(props) {
             // eslint-disable-next-line react/jsx-props-no-spreading
             {...props}
             ref={innerRef}
-            shouldMeasureItems
             contentContainerStyle={contentContainerStyle}
             onScroll={handleScroll}
         />

src/pages/home/report/ReportActionsList.js

@@ -420,7 +420,6 @@ function ReportActionsList({
                     renderItem={renderItem}
                     contentContainerStyle={contentContainerStyle}
                     keyExtractor={keyExtractor}
-                    initialRowHeight={32}
                     initialNumToRender={initialNumToRender}
                     onEndReached={loadOlderChats}
                     onEndReachedThreshold={0.75}