인프런 커뮤니티 질문&답변

// Home.js

import { useState, useContext, useEffect } from "react";
import { DiaryStateContext } from "../App";

import MyButton from "./../components/MyButton";
import MyHeader from "./../components/MyHeader";
import DiaryList from "./../components/DiaryList";

const Home = () => {
  const diaryList = useContext(DiaryStateContext);

  const [data, setData] = useState([]);
  const [curDate, setCurDate] = useState(new Date());
  const headText = `${curDate.getFullYear()}년 ${curDate.getMonth() + 1}월`;

  useEffect(() => {
    if (diaryList.length >= 1) {
      const firstDay = new Date(
        curDate.getFullYear(),
        curDate.getMonth(),
        1
      ).getTime();

      const lastDay = new Date(
        curDate.getFullYear(),
        curDate.getMonth() + 1,
        0
      ).getTime();

      setData(
        diaryList.filter((it) => firstDay <= it.date && it.date <= lastDay)
      );
    }
  }, [diaryList, curDate]);

  useEffect(() => {
    console.log(data);
  }, [data]);

  const increaseMonth = () => {
    setCurDate(
      new Date(curDate.getFullYear(), curDate.getMonth() + 1, curDate.getDate())
    );
  };

  const decreaseMonth = () => {
    setCurDate(
      new Date(curDate.getFullYear(), curDate.getMonth() - 1, curDate.getDate())
    );
  };

  return (
    <div>
      <MyHeader
        headText={headText}
        leftChild={<MyButton text={"<"} onClick={decreaseMonth} />}
        rightChild={<MyButton text={">"} onClick={increaseMonth} />}
      />
      <DiaryList diaryList={data} />
    </div>
  );
};

export default Home;

// DiaryList.js

import { useState } from "react";

const sortOptionList = [
  { value: "latest", name: "최신순" },
  { value: "oldest", name: "오래된 순" },
];

const ControlMenu = ({ value, onChange, optionList }) => {
  return (
    <select value={value} onChange={(e) => onChange(e.target.value)}>
      {optionList.map((it, idx) => (
        <option key={idx} value={it.value}>
          {it.name}
        </option>
      ))}
    </select>
  );
};

const DiaryList = ({ diaryList }) => {
  const [sortType, setSortType] = useState("lastest");

  return (
    <div>
      <ControlMenu
        value={sortType}
        onChange={setSortType}
        optionList={sortOptionList}
      />
      {diaryList.map((it) => (
        <div key={it.id}>{it.content}</div>
      ))}
    </div>
  );
};

DiaryList.defaultProps = {
  diaryList: [],
};

export default DiaryList;

// App.js

import React, { useReducer, useRef } from "react";

import "./App.css";
import { BrowserRouter, Routes, Route } from "react-router-dom";

import Home from "./pages/Home";
import New from "./pages/New";
import Edit from "./pages/Edit";
import Diary from "./pages/Diary";

const reducer = (state, action) => {
  let newState = [];
  switch (action.type) {
    case "INIT": {
      return action.data;
    }
    case "CREATE": {
      const newItem = {
        ...action.data,
      };
      newState = [newItem, ...state];
      break;
    }
    case "REMOVE": {
      newState = state.filter((it) => it.id !== action.targetId);
      break;
    }
    case "EDIT": {
      newState = state.map((it) =>
        it.id === action.data.id ? { ...action.data } : it
      );
      break;
    }
    default:
      return state;
  }
  return newState;
};

export const DiaryStateContext = React.createContext();
export const DiaryDispatchContext = React.createContext();

const dummyData = [
  {
    id: 1,
    emotion: 1,
    content: "오늘의일기 1번",
    date: 1704809815768,
  },
  {
    id: 2,
    emotion: 2,
    content: "오늘의일기 2번",
    date: 1704809815769,
  },
  {
    id: 3,
    emotion: 3,
    content: "오늘의일기 3번",
    date: 1704809815770,
  },
  {
    id: 4,
    emotion: 4,
    content: "오늘의일기 4번",
    date: 1704809815771,
  },
  {
    id: 5,
    emotion: 5,
    content: "오늘의일기 5번",
    date: 1704809815772,
  },
];

function App() {
  const [data, dispatch] = useReducer(reducer, dummyData);

  console.log(new Date().getTime());

  const dataId = useRef(0);
  // CREATE
  const onCreate = (date, content, emotion) => {
    dispatch({
      type: "CREATE",
      data: {
        id: dataId.current,
        date: new Date(Date).getTime(),
        content,
        emotion,
      },
    });
    dataId.current += 1;
  };
  // REMOVE
  const onRemove = (targetId) => {
    dispatch({ type: "REMOVE", targetId });
  };
  // EDIT
  const onEdit = (targetId, date, content, emotion) => {
    dispatch({
      type: "EDIT",
      data: {
        id: targetId,
        date: new Date(Date).getTime(),
        content,
        emotion,
      },
    });
  };
  return (
    <DiaryStateContext.Provider value={data}>
      <DiaryDispatchContext.Provider value={{ onCreate, onEdit, onRemove }}>
        <BrowserRouter>
          <div className="App">
            <Routes>
              <Route path="/" element={<Home />} />
              <Route path="/new" element={<New />} />
              <Route path="/edit" element={<Edit />} />
              <Route path="/diary/:id" element={<Diary />} />
            </Routes>
          </div>
        </BrowserRouter>
      </DiaryDispatchContext.Provider>
    </DiaryStateContext.Provider>
  );
}

export default App;

해당 강의 23분경부터 계속 막힙니다.

아무리 정렬을 바꿔도 정렬이 변경되지 않아요. 따라친다고 따라쳤는데 어디가 틀린지 잘 모르겠습니다.