标签: scrolltoindex

我的反应本机应用程序中有此类别过滤器组件。第一次加载该组件时，它不会滚动到给定的索引项（即 3）。我检查了一下，该函数scrollToIndex正在调用。但是加载屏幕后，当组件重新渲染时它就可以工作了。

为什么它在第一次加载屏幕时不向下滚动？

import React, { useCallback, useRef } from 'react'
import { StyleSheet, TouchableOpacity, FlatList, View } from 'react-native'
import { Badge, Text } from 'native-base'
import { connect } from 'react-redux'
import * as categoryActions from '../../Redux/Actions/categoryActions'
import { useFocusEffect } from '@react-navigation/native'

const CategoryFilter = (props) => {
  const flatlistRef = useRef()

  const handleSetSelectedCategoryId = (categoryId) => {
    props.setSelectedCategoryId(categoryId)
  }

  const getItemLayout = (data, index) => ({
    length: 50,
    offset: 50 * index,
    index,
  }) …