ref

src/Admin.js

-import React, { useState, useEffect } from 'react';
+import React, { useState, useEffect, useRef } from 'react';
 import AdminQuiz from './AdminQuiz'
 import AdminSetting from './AdminSetting'
 
 let QuizBtn = []
-let QnAadmins
+
 function Admin() {
 
     const [result, setresult] = useState('')
     const [QuizBtnCount, setQuizBtnCount] = useState(4)
-    const [n, setn] = useState(0)
+    const indexRef = useRef(0)
+    const dbRef = useRef([])
+
 
+    useEffect(() => {
+        if (JSON.parse(localStorage.getItem('QnA'))) {
+            dbRef.current=JSON.parse(localStorage.getItem('QnA'))
+        }
+    }, [])
 
     function handleClickSetting() {
         setresult(<AdminSetting />)
     }
 
     function handleClickQuiz(e) {
-        if (QnAadmins) {
-            let QnAadmins = []
-            setn(e.target.id)
-            setresult(<AdminQuiz quizNum={e.target.id} fn={handleClickSave} data={QnAadmins} />)
-        }
-        else {
-            setn(e.target.id)
-            // let QnAadmins = []
-            let QnAadmins = JSON.parse(localStorage.getItem('QnA'))
-            console.log(QnAadmins)
-            setresult(<AdminQuiz quizNum={e.target.id} fn={handleClickSave} data={QnAadmins[Number(n)]} />)
-        }
+        indexRef.current = Number(e.target.id) - 1
+        console.log(dbRef.current, indexRef.current)
+        setresult(<AdminQuiz quizNum={e.target.id} fn={handleClickSave} data={dbRef.current} />)
+
     }
 
     function handleClickAddQuiz() {
@@ -38,25 +37,27 @@ function Admin() {
     }
 
     function handleClickSave(QnAadmin) {
-        QnAadmins.splice(n, 0, QnAadmin)
-        localStorage.setItem('QnA', JSON.stringify(QnAadmins))
+        console.log(QnAadmin, indexRef.current)
+        dbRef.current[indexRef.current] = QnAadmin
+        localStorage.setItem('QnA', JSON.stringify(dbRef.current))
+
     }
 
     return (
         <>
-            <div className="container-fluid">
+            <div className="container-fluid bg-light">
                 <div className="row justify-content-md-center mt-5">
                     <div className="col-2 text-center border py-5 bg-white">
                         <div className="py-3 border-top border-bottom">
-                            <h5 className="font-weight-bold">ADMIN</h5>
+                            <h5 className="font-weight-bold">설정</h5>
                         </div>
                         <div className="border-bottom py-4">
                             <button type="button" className="btn btn-info" onClick={handleClickSetting}>Setting</button>
                         </div>
                         <div className="btn-group-vertical py-4">
-                            <button type="button" className="btn btn-outline-primary" id="1" onClick={handleClickQuiz}>Quiz 1</button>
-                            <button type="button" className="btn btn-outline-primary" id="2" onClick={handleClickQuiz}>Quiz 2</button>
-                            <button type="button" className="btn btn-outline-primary" id="3" onClick={handleClickQuiz}>Quiz 3</button>
+                            <button type="button" className="btn btn-outline-primary" id={1} onClick={handleClickQuiz}>Quiz 1</button>
+                            <button type="button" className="btn btn-outline-primary" id={2} onClick={handleClickQuiz}>Quiz 2</button>
+                            <button type="button" className="btn btn-outline-primary" id={3} onClick={handleClickQuiz}>Quiz 3</button>
                             {QuizBtn.map((element) => element)}
                             <button type="button" className="btn btn-outline-primary" onClick={handleClickAddQuiz}>+</button>
 

src/AdminQuiz.js

-import React, { useState, useEffect} from 'react';
+import React, { useState} from 'react';
 
 let list = []
 let QnAadmin = {}
@@ -53,7 +53,7 @@ function AdminQuiz(props) {
         }
         else {
             QnAadmin['Choose'] = Object.values(savechoose)
-            QnAadmin['N'] = String(props.QuizNum)
+            QnAadmin['N'] = String(props.quizNum)
             props.fn(QnAadmin)
             QnAadmin = {}
             alert('입력이 완료되었습니다.')
@@ -65,7 +65,7 @@ function AdminQuiz(props) {
 
     return (
         <div className="" id="Quiz1">
-            <h2 className="p-3 border text-center">{String(props.quizNum)}번 문제만들기</h2>
+            <h2 className="p-3 border text-center bg-white">{String(props.quizNum)}번 문제만들기</h2>
             <div className="p-3 borber">
                 <div className="p-3 ">
                     <span className="font-weight-bold mr-2 h3">1. 문제 입력하기</span>

src/AdminSetting.js

@@ -47,19 +47,19 @@ function AdminSetting() {
 
     }
     return (
-        <div className="col-8">
-            <h2 className="p-3 border text-center">관리자 설정 변경 창</h2>
-            <div className="p-3 border">
+        <div className="">
+            <h2 className="p-3 border text-center bg-white">관리자 설정 변경 창</h2>
+            <div className="p-3 border bg-white">
                 <h4>변경할 비밀번호를 입력하세요</h4>
                 <input type="text" onChange={handleChangePassword} placeholder="New Password" />
 
             </div>
-            <div className="p-3 border">
+            <div className="p-3 border bg-white">
                 <h4>변경할 관리자 비밀번호를 입력하세요</h4>
                 <input type="text" onChange={handleChangeAdminPassword} placeholder="New Admin Password" />
 
             </div>
-            <div className="p-3 border">
+            <div className="p-3 border bg-white">
                 <h4>타이머를 설정하세요(초단위)</h4>
                 <input type="text" onChange={handleChangeTime} placeholder="Set Time" />
 

src/App.js

@@ -10,9 +10,9 @@ function App() {
   return (
     <Router>
       <div className="container-fluid vh-100 bg-light">
-        <header className="border-bottom">
+        <header className="border-bottom bg-white">
           <Link to="/">
-            <button className="ml-3 btn btn-light btn-lg font-weight-bold text-info">Home</button>
+            <button className="ml-3 btn btn-white btn-lg font-weight-bold text-info">Home</button>
           </Link>
         </header>
         <Switch>