我正在构建一个React Native应用程序。 我的应用程序有5个屏幕:主页(initialRouteName),DeckPage,QuestionPage,NewCardPage,NewDeckPage。 (按此顺序) 我正在使用Redux进行状态管理。状态正在从AsyncStorage更新。 通过派遣componentDidMount中的“获取”功能,完成获取的组件就是类组件“主页”。
组件NewCardPage,NewDeckPAge还通过在按下按钮时分派与Home相同的提取功能来用新内容更新状态。
当我想从DeckPage父组件内部删除Deck组件时出现我的问题。完成此任务的功能具有以下功能:从AsyncStorage删除项目后,更新STATE,然后移回Screen HOME。问题是,当我返回HOME组件时,状态不会使用AsyncStorage的最新信息进行更新。 当我在其他2个组件NewCardPage,NewDeckPage中执行相同的操作时,情况并非如此。
我将粘贴以下代码:
import React, { Component } from "react";
import { connect } from "react-redux";
import { View, Text, StyleSheet, FlatList } from "react-native";
import Header from "../components/Header";
import AddDeckButton from "../components/AddDeckButton";
import DeckInList from "../components/DeckInList";
import { receiveItemsAction } from "../redux/actions";
class Home extends Component {
componentDidMount() {
this.props.getAsyncStorageContent();
}
renderItem = ({ item }) => {
return <DeckInList {...item} />;
};
render() {
const { items } = this.props;
// console.log(items);
const deckNumber = Object.keys(items).length;
return (
<View style={styles.container}>
<Header />
<View style={styles.decksInfoContainer}>
<View style={styles.deckNumber}>
<View style={{ marginRight: 50 }}>
<Text style={styles.deckNumberText}>{deckNumber} Decks</Text>
</View>
<AddDeckButton />
</View>
<View style={{ flex: 0.9 }}>
<FlatList
data={Object.values(items)}
renderItem={this.renderItem}
keyExtractor={(item) => item.title}
/>
</View>
</View>
</View>
);
}
}
const mapStateToProps = (state) => {
return {
items: state.items,
};
};
const mapDispatchToProps = (dispatch) => {
return {
getAsyncStorageContent: () => dispatch(receiveItemsAction()),
};
};
----------- DECKPAGE组件------------
import React from "react";
import { View, StyleSheet } from "react-native";
import Deck from "../components/Deck";
import { useSelector, useDispatch } from "react-redux";
import { removeItemAction, receiveItemsAction } from "../redux/actions";
import AsyncStorage from "@react-native-community/async-storage";
const DeckPage = ({ route, navigation }) => {
const { title, date } = route.params;
const questions = useSelector((state) => state.items[title].questions);
const state = useSelector((state) => state.items);
const dispatch = useDispatch();
// const navigation = useNavigation();
const handleRemoveIcon = async () => {
await AsyncStorage.removeItem(title, () => {
dispatch(receiveItemsAction());
navigation.goBack();
});
};
console.log(state);
return (
<View style={styles.deckPageContainer}>
<Deck
handleRemoveIcon={handleRemoveIcon}
title={title}
questions={questions}
date={date}
/>
</View>
);
};
-----------这是我的ACTIONS文件----------
import AsyncStorage from "@react-native-community/async-storage";
export const RECEIVE_ITEMS = "RECEIVE_ITEMS";
// export const REMOVE_ITEM = "REMOVE_ITEM";
export const receiveItemsAction = () => async (dispatch) => {
const objectValues = {};
try {
const keys = await AsyncStorage.getAllKeys();
if (keys.length !== 0) {
const jsonValue = await AsyncStorage.multiGet(keys);
if (jsonValue != null) {
for (let element of jsonValue) {
objectValues[element[0]] = JSON.parse(element[1]);
}
dispatch({
type: RECEIVE_ITEMS,
payload: objectValues,
});
} else {
return null;
}
}
} catch (e) {
console.log(e);
}
};
-----这是我的REDUCERS文件----
import { RECEIVE_ITEMS, REMOVE_ITEM } from "./actions";
const initialState = {
};
const items = (state = initialState, action) => {
switch (action.type) {
case RECEIVE_ITEMS:
return {
...state,
...action.payload,
};
// case REMOVE_ITEM:
// return {
// ...state,
// ...action.payload,
// };
default:
return state;
}
}
export default items;
-----这是我的UTILS文件----
import AsyncStorage from "@react-native-community/async-storage";
export const removeDeckFromAsyncStorage = async (title)=>{
try{
await AsyncStorage.removeItem(title);
}
catch(e){
console.log(`Error trying to remove deck from AsyncStorage ${e}`);
}
}