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Start your free trialJames Crosslin
Full Stack JavaScript Techdegree Graduate 16,882 PointsIf you chose to try this course with React hooks, it can start to get tricky here. My solution if you're struggling
I did change a little, like putting in an empty array in anticipation of having to empty it anyway later. I also disliked the index method of locating which player to remove, so I used the players unique ids which feels safer to me.
App.js
import React, { useState } from "react";
import Header from "./Header";
import Player from "./Player";
import AddPlayerForm from "./AddPlayerForm";
function App() {
const [players, setPlayers] = useState([]);
const [playerId, setPlayerId] = useState(0);
const handleScoreChange = (id, addend) => {
setPlayers((players) => {
const clone = [...players];
clone.find((player) => player.id === id).score += addend;
return clone;
});
};
const handleRemovePlayer = (id) =>
setPlayers((players) => players.filter((playerObj) => playerObj.id !== id));
const createId = () => {
setPlayerId((id) => id + 1);
return playerId;
};
const handleAddPlayer = (name) =>
setPlayers((players) => {
const playerObj = {
name,
id: createId(),
score: 0,
};
return [...players, playerObj];
});
return (
<div className="scoreboard">
<Header
title="Scoreboard"
totalPlayers={players.length}
totalScore={[...players].reduce((acc, player) => acc + player.score, 0)}
/>
{/* Players List */}
{players.map((player) => (
<Player
{...player}
key={player.id.toString()}
removePlayer={handleRemovePlayer}
changeScore={handleScoreChange}
/>
))}
<AddPlayerForm addPlayer={handleAddPlayer} />
</div>
);
}
export default App;
AddPlayerForm.js
import React, { useState } from "react";
function AddPlayerForm(props) {
const [nameField, setNameField] = useState("");
const {addPlayer} = props;
const handleNameFieldChange = (e) => setNameField(e.target.value);
const handleSubmit = (e) => {
e.preventDefault();
addPlayer(nameField)
setNameField("");
};
return (
<form onSubmit={ handleSubmit }>
<input
type="text"
value={nameField}
onChange={handleNameFieldChange}
placeholder="Enter a player's name"
/>
<input type="submit" value="Add Player" />
</form>
);
}
export default AddPlayerForm;