Bad Android Scrolling Performance

Describe the bug When we have a high amount of images displayed in a ScrollVIew or FlatList, scrolling does not really work when we use FastImage on Android. The same code works very well on iOS Devices.

To Reproduce I tested this example code in a plain react-native app and the same behavior was recognized:

import { FlatList, View, ScrollView } from 'react-native'
import FastImage from 'react-native-fast-image'
const data = Array(100).fill(1)

const App = () => {
    return (
        <View style={{ flex: 1 }}>
            <ScrollView style={{ backgroundColor: '#000' }}>
                {data.map((element, index) => {
                    return (
                        <FastImage
                            onError={() => console.log('error', index)}
                            source={{ uri: `https://picsum.photos/id/${index}/450/253` }}
                            style={{ width: '100%', aspectRatio: 16 / 9 }}
                        />
                    )
                })}
            </ScrollView>
        </View>
    )
}

Expected behavior Smooth scrolling also on android devices

Dependency versions

• React Native version: 0.61.4
• React version: 16.11.0
• React Native Fast Image version: 7.0.2

[hjhimanshu01]

@klaaz0r , did u made it working with scrollView? UPDATE: made it working using removeClippedSubviews={true} for ScrollView

[yaronlevi]

Same here RN@0.61.5 Many horizontal Flatlists and on Android it sluggish and feels slow. On iOS, it works fine.