react-native - 无法使用 UseCallback 内部的参数访问函数

Question

我有这个页面（屏幕）通过参数接收一个 ID 号，在这个屏幕中，我尝试从我的动作（减速器）文件中调用一个动作函数并获得一个 API 调用，我以为我没有得到任何信息来自该调用的数组，我认为问题出在调用中，但是我在操作函数的声明之后放置了一个控制台日志，但它没有打印，所以我认为它没有访问该函数，所以我相信问题在于通过调度调用该函数。

我什至尝试在 UseEfect 中放置一个断点，在那里我调用调用 Dispatch 函数的函数，但它从不中断我不确定错误在哪里，这是代码：

屏幕（我怀疑问题出在哪里）：

      ```import React, {useState, useCallback, useEffect} from 'react';

      import { ScrollView, Text, Image, StyleSheet, View } from 'react-native';

      import { useSelector, useDispatch } from 'react-redux';

      const ProductDetailScreen = props => {
          const playerId = props.route.params.id;
          const estadId = props.route.params.statId;

          const selectedPlayer = useSelector(state => state.jugadores.availablePlayers.find(prod => prod.id === playerId));


      const [isLoading, setIsLoading] = useState(false);
      const [isRefreshing, setIsRefreshing] = useState(false);
      const [error, setError] = useState();

      const goles = useSelector(state => state.jugadores.playerGoals);

      const dispatch = useDispatch();

      const loadEstad = useCallback (async (param) => {
          setError(null);
          setIsRefreshing(true);
          try {
              await dispatch(userActions.fetchEstadistica(param));
          } catch (err){
              setError(err.message);
          }
          setIsRefreshing(false);
      }, [dispatch, setIsLoading, setError]);

      useEffect(() => {       
          setIsLoading(true); 
          loadEstad(estadId).then(() => {
              setIsLoading(false);
          });
      }, [dispatch, loadEstad]);

      console.log(estadId);
      console.log(goles);

      return (
          <ScrollView>
              <Image style={styles.image} source={{ uri: selectedPlayer.imagen }} />
              <View style={styles.dataContainer}>
                  <Text style={styles.description}>Numero: <Text style={styles.subtitle}>{selectedPlayer.numero}</Text></Text>
                  <Text style={styles.description}>Nombre Completo: <Text style={styles.subtitle}>{selectedPlayer.nombre_completo}</Text></Text>
                  <Text style={styles.description}>Posicion: <Text style={styles.subtitle}>{selectedPlayer.posicion}</Text> </Text>
                  <Text style={styles.description}>Edad: <Text style={styles.subtitle}>{selectedPlayer.edad}</Text></Text>
                  <Text style={styles.description}>Nacionalidad: <Text style={styles.subtitle}>{selectedPlayer.nacionalidad}</Text></Text>
              </View>
          </ScrollView>
      );
  }

;

      export const screenOptions = navData => {
          return {
              headerTitle: navData.route.params.nombre,


    }
      };

      const

styles = StyleSheet.create({ image: { width: '100%', height: 300, }, subtitle: { fontSize: 16, textAlign: 'justify', marginVertical: 20, fontWeight:'normal', }, 描述： { fontSize: 16, textAlign: 'center', marginVertical: 20, fontWeight: 'bold',

          },
          dataContainer:{
              width: '80%',
              alignItems: 'center',
              marginHorizontal: 40,
          },
          actions: {
              marginVertical: 10,
              alignItems: 'center',
          },
      });

      export default ProductDetailScreen

  ;```

这是我的行动文件：

import ResultadoEstadistica from '../../models/estadistica/resultadoEstadistica';
import PlayerEstadistica from '../../models/estadistica/playerEstatisticData';
import Cards from '../../models/estadistica/cards';
import Games from '../../models/estadistica/games';
import Goals from '../../models/estadistica/goals';

export const SET_JUGADORES = 'SET_JUGADORES';
export const SET_ESTADISTICA = 'SET_ESTADISTICA';

export const fetchJugadores = () => {
    return async (dispatch) => {
        //any async code here!!!
        try {
            const response = await fetch(
                'https://alianzafc2021-default-rtdb.firebaseio.com/jugadores.json'
            );

            if (!response.ok) {
                throw new Error('Algo salio Mal!');
            }

            const resData = await response.json();
            const loadedJugadores = [];

            for (const key in resData) {
                loadedJugadores.push(
                    new Jugador(
                        key,
                        resData[key].altura,
                        resData[key].apellido,
                        resData[key].edad,
                        resData[key].fecha_nacimiento,
                        resData[key].iso_code,
                        resData[key].imagen,
                        resData[key].lugar_nacimiento,
                        resData[key].nacionalidad,
                        resData[key].nombre_completo,
                        resData[key].nombre_corto,
                        resData[key].nombres,
                        resData[key].numero,
                        resData[key].pais,
                        resData[key].peso,
                        resData[key].player_id,
                        resData[key].posicion
                    )
                );
            }

            dispatch({ type: SET_JUGADORES, players: loadedJugadores });
        } catch (err) {
            throw err;
        }
    };
}

export const fetchEstadistica = player_id => {
    return async (dispatch) => {
        //any async code here!!!
        try {
            const response = await fetch(
                `https://api-football-v1.p.rapidapi.com/v2/players/player/${player_id}.json`,
                {
                    method: 'GET',
                    headers: {
                        'x-rapidapi-key': Here goes my API KEY,
                        'x-rapidapi-host': 'api-football-v1.p.rapidapi.com',
                        'useQueryString': 'true'
                    }
                }
            );

            if (!response.ok) {
                throw new Error('Algo salio Mal!');
            }

            const resData = await response.json();
            const loadesApiResult = [];

            console.log('***Impresion desde la accion***');
            console.log(resData);
            console.log('***Fin de Impresionc***');

            //Arrays de la Estadistica del Jugador
            const loadedEstadistica = [];
            const loadedCards = [];
            const loadedGoals = [];
            const loadedGames = [];

            for (const key in resData) {
                loadesApiResult.push(
                    new ResultadoEstadistica(
                        resData[key].results,
                        resData[key].players
                    )
                );
            }

            const apiData = loadesApiResult.players;

            for (const key in apiData) {
                loadedEstadistica.push(
                    new PlayerEstadistica(
                        apiData[key].player_id,
                        apiData[key].player_name,
                        apiData[key].firstname,
                        apiData[key].lastname,
                        apiData[key].number,
                        apiData[key].position,
                        apiData[key].age,
                        apiData[key].birth_date,
                        apiData[key].birth_place,
                        apiData[key].birth_country,
                        apiData[key].nationality,
                        apiData[key].height,
                        apiData[key].weight,
                        apiData[key].injured,
                        apiData[key].rating,
                        apiData[key].team_id,
                        apiData[key].team_name,
                        apiData[key].league_id,
                        apiData[key].league,
                        apiData[key].season,
                        apiData[key].captain,
                        apiData[key].shots,
                        apiData[key].goals,
                        apiData[key].passes,
                        apiData[key].duels,
                        apiData[key].dribbles,
                        apiData[key].fouls,
                        apiData[key].cards,
                        apiData[key].penalty,
                        apiData[key].games,
                        apiData[key].substitutes,
                    )
                );
            }

            const playerDataGames = loadedEstadistica.games;

            for (const key in playerDataGames) {
                loadedGames.push(
                    new Games(
                        playerDataGames[key].apperences,
                        playerDataGames[key].minutes_played,
                        playerDataGames[key].lineups
                    )
                );
            };

            const playerDataGoals = loadedEstadistica.goals;

            for (const key in playerDataGoals) {
                loadedGoals.push(
                    new Goals(
                        playerDataGoals[key].total,
                        playerDataGoals[key].conceded,
                        playerDataGoals[key].assists,
                        playerDataGoals[key].saves
                    )
                );
            };

            const playerDataCards = loadedEstadistica.cards;

            for (const key in playerDataCards) {
                loadedCards.push(
                    new Cards(
                        playerDataCards[key].yellow,
                        playerDataCards[key].yellowred,
                        playerDataCards[key].red
                    )
                );
            };

            dispatch({ type: SET_ESTADISTICA, estadistica: loadesApiResult, goles: loadedGoals, juegos: loadedGames, tarjetas: loadedCards });
        } catch (err) {
            throw err;
        }
    };
};```

最后，这是我的 Redux Reducer 以防万一：

import { SET_JUGADORES, SET_ESTADISTICA } from "../actions/jugadores";

const initialState = {
    availablePlayers: [],
    estadistica: [],
    playerGoals: [],
    playerCards: [],
    playerGames: [],
}

export default (state = initialState, action) => {
    switch (action.type) {
        case SET_JUGADORES:
            return {
                ...state,
                availablePlayers: action.players,
            };
        case SET_ESTADISTICA:
            return{
                ...state,
                estadistica: estadistica,
                playerGoals: action.goles,
                playerCards: action.tarjetas,
                playerGames: action.juegos
            };
    }
    return state;
};

对不起格式，但给了我一些问题；任何想法我的问题是什么？

谢谢你。

score 0 · Accepted Answer

您的代码存在一些问题screen，因此我建议在添加其他任何内容之前简化逻辑以确保其正常工作。

替换这个：

const loadEstad = useCallback (async (param) => {
          setError(null);
          setIsRefreshing(true);
          try {
              await dispatch(userActions.fetchEstadistica(param));
          } catch (err){
              setError(err.message);
          }
          setIsRefreshing(false);
      }, [dispatch, setIsLoading, setError]);

      useEffect(() => {       
          setIsLoading(true); 
          loadEstad(estadId).then(() => {
              setIsLoading(false);
          });
      }, [dispatch, loadEstad]);

      console.log(estadId);
      console.log(goles);

有了这个：

useEffect(()=>{
if (estadId) dispatch(userActions.fetchEstadistica(estadId));
},[estadId]);

假设您的减速器/操作代码是正确的，那么每次参数estadId更改时都应该调用 api。加载/刷新应该在 reducer 中设置，而不是在screen组件上。

需要记住的几件事：

不要等待发货。
承诺解析代码块之外的状态变量上的 console.log 将不起作用。
下面的这行不通。相反，您应该将加载变量设置为在 API 返回数据后更新的 redux 变量。

loadEstad(estadId).then(() => { setIsLoading(false); });

react-native - 无法使用 UseCallback 内部的参数访问函数

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