如何在反应原生 mobx 中设置数组值？

Posted 2023-02-16

【中文标题】如何在反应原生 mobx 中设置数组值？

【英文标题】：How to set array value in react native mobx?

【发布时间】：2022-01-01 13:03:00

【问题描述】：

我有 favoriteStore，而且我是 mobx 的新手，我想将数组从 bookmarkapi 设置为 petList 数组，但我遇到了错误。

错误；

[Unhandled promise rejection: TypeError: undefined is not an object (evaluating '_this2.userId')]

代码；

import  observable, computed, action, makeObservable, configure  from "mobx";
import  bookmarkApi, petApi  from '../../constants/apiURL';
import AsyncStorage from '@react-native-async-storage/async-storage';

configure(
    enforceActions: "never",
)

class Favorites 
    userId = 0;
    petList = [];

    constructor() 
        makeObservable(this, 
            userId: observable,
            petList: observable,
            bookMarkList: action
        )
    

    bookMarkList = async () => 
        const value = await AsyncStorage.getItem('userId')
        if (value != null) 
            this.userId = value;
            console.log(this.userId);
        

        bookmarkApi.get('/').then(function (responseJson) 
            this.petList = responseJson.data.filter(data => data.userId == this.userId)
        )
    


export const favoriteStore = new Favorites();

【参考方案1】：

回调函数丢失上下文，只需使用箭头函数进行bookmarkApi.get回调。