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Can't access prop in another component?

I'm getting myself confused with React here (total newbie). I have a simple component that fetches some data that always returns {"score":100}:
import React, { useEffect, useState } from "react";
import Graph from "./Graph.js";
const UsingFetch = () => {
const [results, setResults] = useState({"score": null}); // initially set score to null
const fetchData = () => {
fetch("https://myapi.com/id=1")
.then((response) => {
return response.json();
})
.then((data) => {
setResults(data); // update results with integer score
});
};
useEffect(() => {
fetchData();
}, []);
console.log(results)
return (
<div>
<Graph results={results.score}></Graph>
</div>
);
};
export default UsingFetch;
My Graph.js looks like the following:
import { React } from 'react'
export default function Graph({results}) {
console.log(results)
return (
<div>
<h1>{results}</h1>
</div>
)
}
Why doesn't the score render on the page? I've confirmed that the data returns correctly, I just can't seem to access it right.
Here's the console output:

Results is an array.
<h1>{results.map((result) => (result.score)}</h1>

How to wait for server response before calling Apollo Graph QL Query?

I'm attempting to call a Graph QL Query after receiving data from my useEffect hook. I need the data from the response to use in the Query. Hooks however cannot be called conditionally. If I take away the condition however, loadedAnime will be undefined. How do I get around this restraint?
import React, { useEffect, useState } from "react";
import { useParams } from "react-router-dom";
import AnimeBanner from "../components/AnimeBanner";
import { useHttpClient } from "../Hooks/http-hook";
import { GetAnimeData } from "../GraphQLFunctions";
import { useQuery } from "#apollo/react-hooks";
import gql from "graphql-tag";
const GET_ANIME_INFO = gql`
query GetAnimeInfo($name: String!) {
Media(search: $name) {
title {
romaji
english
native
userPreferred
}
episodes
id
bannerImage
}
}
`;
const Anime = (props) => {
//Logic for getting anime data from mongoDB (episodes, name, cover image)
const { isLoading, error, sendRequest } = useHttpClient();
const [loadedAnime, setloadedAnime] = useState();
const URLTitle = useParams().URLTitle;
useEffect(() => {
const fetchAnime = async () => {
try {
const responseData = await sendRequest(
"http://localhost:5000/api/anime/" + URLTitle
);
setloadedAnime(responseData.animeData[0]);
} catch (err) {
console.log(err);
}
};
fetchAnime();
}, [sendRequest, URLTitle]);
if (isLoading || error) {
return null;
}
//Logic for getting anime data from anilist (Descriptions, tags, banner, trailer, etc.)
const { apiData, apiLoading, apiError } = useQuery(GET_ANIME_INFO, {
variables: {
name: loadedAnime.anime_name,
},
});
if (apiLoading || apiError) {
return null;
}
return <AnimeBanner src={apiData.Media.bannerImage} />;
};
export default Anime;

Short Answer: You can checkout useLazyQuery instead of useQuery.
Documentation link: https://www.apollographql.com/docs/react/data/queries/#executing-queries-manually
When React mounts and renders a component that calls the useQuery hook, Apollo Client automatically executes the specified query. But what if you want to execute a query in response to a different event, such as a user clicking a button?
The useLazyQuery hook is perfect for executing queries in response to events other than component rendering. This hook acts just like useQuery, with one key exception: when useLazyQuery is called, it does not immediately execute its associated query. Instead, it returns a function in its result tuple that you can call whenever you're ready to execute the query
import React, { useState } from 'react';
import { useLazyQuery } from '#apollo/client';
function DelayedQuery() {
const [dog, setDog] = useState(null);
const [getDog, { loading, data }] = useLazyQuery(GET_DOG_PHOTO);
if (loading) return <p>Loading ...</p>;
if (data && data.dog) {
setDog(data.dog);
}
return (
<div>
{dog && <img src={dog.displayImage} />}
<button onClick={() => getDog({ variables: { breed: 'bulldog' } })}>
Click me!
</button>
</div>
);
}

You can either call the query after the await finishes or you can call your query in another useEffect once you update state after your api call. In general, something like this,
const [state, setState] = useState({})
useEffect(async () => {
const result = await get('/api/blah-blah-blah')
// run your query here now that the await has resolved
}, [someDependency])
or
const [state, setState] = useState({})
useEffect(async () => {
const result = await get('/api/blah-blah-blah')
setState(result)
}, [someDependency])
useEffect(() => {
if(state.id) {
// run the query
}
}, [state.someProp])

React Hooks/Context & Elastictic UI. Problem with fetched data (REST) in function Component

I'm quite new to React Hooks/Context so I'd appreciate some help. Please don' t jump on me with your sharp teeth. I Checked other solutions and some ways i've done this before but can't seem to get it here with the 'pick from the list' way.
SUMMARY
I need to get the municipios list of names inside of my const 'allMunicipios'(array of objects) inside of my Search.js and then display a card with some data from the chosen municipio.
TASK
Get the data from eltiempo-net REST API.
Use Combobox async element from Elastic UI to choose from list of municipios.
Display Card (from elastic UI too) with some info of chosen municipio.
It has to be done with function components / hooks. No classes.
I'd please appreciate any help.
WHAT I'VE DONE
I've created my reducer, context and types files in a context folder to fecth all data with those and then access data from the component.
I've created my Search.js file. Then imported Search.js in App.js.
I've accesed the REST API and now have it in my Search.js
PROBLEM
Somehow I'm not beeing able to iterate through the data i got.
Basically i need to push the municipios.NOMBRE from api to the array const allMunicipios in my search.js component. But when i console log it it gives me undefined. Can;t figure out why.
I'll share down here the relevant code/components. Thanks a lot for whoever takes the time.
municipiosReducer.js
import {
SEARCH_MUNICIPIOS,
CLEAR_MUNICIPIOS,
GET_MUNICIPIO,
GET_WEATHER,
} from "./types";
export default (state, action) => {
switch (action.type) {
case SEARCH_MUNICIPIOS:
return {
...state,
municipios: action.payload,
};
case GET_MUNICIPIO:
return {
...state,
municipio: action.payload,
};
case CLEAR_MUNICIPIOS:
return {
...state,
municipios: [],
};
case GET_WEATHER: {
return {
...state,
weather: action.payload,
};
}
default:
return state;
}
};
municipiosContext.js
import { createContext } from "react";
const municipiosContext = createContext();
export default municipiosContext;
MunicipiosState.js
import React, { createContext, useReducer, Component } from "react";
import axios from "axios";
import MunicipiosContext from "./municipiosContext";
import MunicipiosReducer from "./municipiosReducer";
import {
SEARCH_MUNICIPIOS,
CLEAR_MUNICIPIOS,
GET_MUNICIPIO,
GET_WEATHER,
} from "./types";
const MunicipiosState = (props) => {
const initialState = {
municipios: [],
municipio: {},
};
const [state, dispatch] = useReducer(MunicipiosReducer, initialState);
//Search municipios
//In arrow functions 'async' goes before the parameter.
const searchMunicipios = async () => {
const res = await axios.get(
`https://www.el-tiempo.net/api/json/v2/provincias/08/municipios`
// 08 means barcelona province. This should give me the list of all its municipios
);
dispatch({
type: SEARCH_MUNICIPIOS,
payload: res.data.municipios,
});
};
//Get Municipio
const getMunicipio = async (municipio) => {
const res = await axios.get(
`https://www.el-tiempo.net/api/json/v2/provincias/08/municipios/${municipio.CODIGOINE}`
//CODIGOINE is in this REST API kind of the ID for each municipio.
//I intent to use this later to get the weather conditions from each municipio.
);
dispatch({ type: GET_MUNICIPIO, payload: res.municipio });
};
const dataMunicipiosArray = [searchMunicipios];
//Clear Municipios
const clearMunicipios = () => {
dispatch({ type: CLEAR_MUNICIPIOS });
};
return (
<MunicipiosContext.Provider
value={{
municipios: state.municipios,
municipio: state.municipio,
searchMunicipios,
getMunicipio,
clearMunicipios,
dataMunicipiosArray,
}}
>
{props.children}
</MunicipiosContext.Provider>
);
};
export default MunicipiosState;
Search.js
import "#elastic/eui/dist/eui_theme_light.css";
import "#babel/polyfill";
import MunicipiosContext from "../contexts/municipiosContext";
import MunicipiosState from "../contexts/MunicipiosState";
import { EuiComboBox, EuiText } from "#elastic/eui";
import React, { useState, useEffect, useCallback, useContext } from "react";
const Search = () => {
const municipiosContext = useContext(MunicipiosContext);
const { searchMunicipios, municipios } = MunicipiosState;
useEffect(() => {
return municipiosContext.searchMunicipios();
}, []);
const municipiosFromContext = municipiosContext.municipios;
const bringOneMunicipio = municipiosContext.municipios[0];
let municipiosNames = municipiosFromContext.map((municipio) => {
return { label: `${municipio.NOMBRE}` };
});
console.log(`municipiosFromContext`, municipiosFromContext);
console.log(`const bringOneMunicipio:`, bringOneMunicipio);
console.log(`municipiosNames:`, municipiosNames);
const allMunicipios = [
{ label: "santcugat" },
{ label: "BARCELONETA" },
{ label: "BARCE" },
];
const [selectedOptions, setSelected] = useState([]);
const [isLoading, setLoading] = useState(false);
const [options, setOptions] = useState([]);
let searchTimeout;
const onChange = (selectedOptions) => {
setSelected(selectedOptions);
};
// combo-box
const onSearchChange = useCallback((searchValue) => {
setLoading(true);
setOptions([]);
clearTimeout(searchTimeout);
// eslint-disable-next-line react-hooks/exhaustive-deps
searchTimeout = setTimeout(() => {
// Simulate a remotely-executed search.
setLoading(false);
setOptions(
municipiosNames.filter((option) =>
option.label.toLowerCase().includes(searchValue.toLowerCase())
)
);
}, 1200);
}, []);
useEffect(() => {
// Simulate initial load.
onSearchChange("");
}, [onSearchChange]);
return (
<div>
<EuiComboBox
placeholder="Search asynchronously"
async
options={options}
selectedOptions={selectedOptions}
isLoading={isLoading}
onChange={onChange}
onSearchChange={onSearchChange}
/>
<button>Lista de municipios</button>
</div>
);
};
export default Search;
also the
Home.js
import React, { useState } from "react";
import { EuiComboBox, EuiText } from "#elastic/eui";
// import { DisplayToggles } from "../form_controls/display_toggles";
import "#babel/polyfill";
import "#elastic/eui/dist/eui_theme_light.css";
import Search from "./Search";
import MunicipioCard from "./MunicipioCard";
const Home = () => {
return (
<div>
<EuiText grow={false}>
<h1>Clima en la provincia de Barcelona</h1>
<h2>Por favor seleccione un municipio</h2>
</EuiText>
<Search />
<MunicipioCard />
</div>
);
};
export default Home;
App.js
import "#babel/polyfill";
import "#elastic/eui/dist/eui_theme_light.css";
import { EuiText } from "#elastic/eui";
import React from "react";
import Home from "./components/Home";
import MunicipiosState from "./contexts/MunicipiosState";
import "./App.css";
function App() {
return (
<MunicipiosState>
<div className="App">
<EuiText>
<h1>App Component h1</h1>
</EuiText>
<Home />
</div>
</MunicipiosState>
);
}
export default App;

You are using forEach and assigning the returned value to a variable, however forEach doesn't return anything. You should instead use map
let municipiosNames = municipiosFromContext.map((municipio) => {
return `label: ${municipio.NOMBRE}`;
});
As per your comment:
you data is loaded asynchronously, so it won't be available on first render and since functional components depend on closures, you onSearchChange function takes the value from the closure at the time of creation and even if you have a setTimeout within it the updated value won't reflect
The solution here is to add municipiosFromContext as a dependency to useEffect
const onSearchChange = useCallback((searchValue) => {
setLoading(true);
setOptions([]);
clearTimeout(searchTimeout);
// eslint-disable-next-line react-hooks/exhaustive-deps
searchTimeout = setTimeout(() => {
// Simulate a remotely-executed search.
setLoading(false);
setOptions(
municipiosNames.filter((option) =>
option.label.toLowerCase().includes(searchValue.toLowerCase())
)
);
}, 1200);
}, [municipiosFromContext]);
useEffect(() => {
// Simulate initial load.
onSearchChange("");
}, [onSearchChange]);

I can't save data inside a Hook

I'm learning Hooks with React and I'm trying to do a simple fetch to an API then I'm trying to save that data inside a Hook but It has not been possible for me.
import React, { useState, useEffect } from "react";
function useDogs() {
const [dogs, setDogs] = useState({
data: {}
});
useEffect(() => {
const fectData = async () => {
const data = await fetch("https://dog.ceo/api/breeds/image/random");
setDogs({ data: data.url });
console.log(data.url);
};
fectData();
}, []);
}
function Dogs() {
const dogs = useDogs();
console.log("dogs", dogs);
return <ul>{dogs} dogy</ul>;
}
export default Dogs;
In component Dogs() I'm having dogs as undefined

You aren't returning dogs from your useDogs hook.
(Also, to get at the response data, you need to await on .json() from the fetch response.)
import React, { useState, useEffect } from "react";
function useDogs() {
const [dogs, setDogs] = useState({
data: {},
});
useEffect(() => {
const getData = async () => {
const resp = await fetch("https://dog.ceo/api/breeds/image/random");
const data = await resp.json(); // <-- this
setDogs({ data });
console.log(resp, data);
};
getData();
}, []);
return dogs; // <-- this
}
function Dogs() {
const dogs = useDogs();
console.log("dogs", dogs);
return <ul>{dogs} dogy</ul>;
}
export default Dogs;

Custom Hooks are just javascript functions if you want to assign them to a variable you need to return something in your custom hook,
In some situations you need to set Something into your custom hook which you can do that by returning both value and setValue functions, for example in your case like below:
import React, { useState, useEffect } from "react";
function useDogs() {
const [dogs, setDogs] = useState({
data: {},
});
useEffect(() => {
const getData = async () => {
const resp = await fetch("https://dog.ceo/api/breeds/image/random");
const data = await resp.json(); // <-- this
setDogs({ data });
console.log(resp, data);
};
getData();
}, []);
return [dogs, setDogs]; // <-- this
}
and when you want to use it you just destructure it like this:
function Dogs() {
const [dogs, setDogs] = useDogs();
console.log("dogs", dogs);
return <ul>{dogs} dogy</ul>;
}
export default Dogs;
now you can read the data and also in future cases if you'ld like you can set the data too,

Easy Peasy state managment - How to fetch and pass data correctly?

I am using Easy Peasy State management for React. I would like to create multiple Axios call from one store location and import it in each page there where I need to show the correct data. I am trying to fetch a JSON placeholder data for example and use that inside a component to push it to the state using Hooks.
But I get the following error:
model.js:14 Uncaught (in promise) TypeError: actions.setTodos is not a function
at model.js:14
Can someone help me out? What am I doing wrong?
My code for the store (model.js):
import { thunk } from 'easy-peasy';
export default {
todos: [],
fetchTodos: thunk(async actions => {
const res = await fetch(
'https://jsonplaceholder.typicode.com/todos?_limit=10'
);
const todos = res.json();
actions.setTodos(todos);
}),
};
My Page component Contact:
import React, { useState, useEffect } from 'react';
import { useStoreActions } from 'easy-peasy';
import ReactHtmlParser from 'react-html-parser';
import { API_URL } from 'constants/import';
// import axios from 'axios';
const Contact = () => {
const [contactPage, setContactPage] = useState([]);
const { page_title, page_content, page_featured_image } = contactPage;
const fetchTodos = useStoreActions(actions => actions.fetchTodos);
useEffect(() => {
fetchTodos();
}, []);
return (
<section className="contact">
<div className="page">
<div className="row">
<div className="col-xs-12">
<h3 className="section__title">{page_title}</h3>
{ReactHtmlParser(page_content)}
{page_featured_image && (
<img src={API_URL + page_featured_image.path} />
)}
</div>
</div>
</div>
</section>
);
};
export default Contact;

You need to use action.
import { action, thunk } from "easy-peasy";
export default {
fetchTodos: thunk(async (actions, payload) => {
const res = await fetch(
"https://jsonplaceholder.typicode.com/todos?_limit=10"
);
const todos = res.json();
actions.setTodos(todos);
}),
todos: [],
setTodos: action((state, payload) => {
console.log("---->>> payload!")
state.todos = payload
}),
};
I usually use it like this, it works perfectly for me.