---
id: 65a609f6e23f3b06c608fb57
title: Step 30
challengeType: 0
dashedName: step-30
---
# --description--
The `sort()` method accepts a compare callback function that defines the sort order.
In this example, the first condition `(a.name < b.name)` checks if the name of the first fruit is less than the name of the second fruit. If so, the first fruit is sorted before the second fruit.
Strings are compared lexicographically which means they are compared character by character. For example, `"Apples"` is less than `"Bananas"` because `"A"` comes before `"B"` in the alphabet.
The reason why this example is returning numbers is because the `sort()` method is expecting a number to be returned. If you return a negative number, the first item is sorted before the second item.
```js
const fruits = [
{ name: "Apples", price: 0.99 },
{ name: "Blueberries", price: 1.49 },
{ name: "Grapes", price: 2.99 },
];
fruits.sort((a, b) => {
if (a.name < b.name) {
return -1;
}
if (a.name > b.name) {
return 1;
}
return 0;
});
```
Inside your callback function, add an `if` statement to check if `a.title` is less than `b.title`. If so, return `-1`.
# --hints--
You should have an `if` statement inside your callback function.
```js
assert.match(code, /if\s*\(/);
```
Your `if` statement should check if `a.title` is less than `b.title`.
```js
assert.match(code, /if\s*\(\s*a\.title\s*<\s*b\.title\s*\)/);
```
Your `if` statement should return `-1` if `a.title` is less than `b.title`.
```js
assert.match(code, /if\s*\(\s*a\.title\s*<\s*b\.title\s*\)\s*{\s*return\s*-1\s*;?\s*}|if\s*\(\s*a\.title\s*<\s*b\.title\s*\)\s*return\s*-1\s*;?/);
```
# --seed--
## --seed-contents--
```html
Learn Basic String and Array Methods by Building a Music Player App
```
```css
:root {
/* colors */
--primary-color: #dfdfe2;
--secondary-color: #ffffff;
--app-background-color: #4d4d62;
--background-color: #1b1b32;
--foreground-color: #3b3b4f;
--highlight-color: #f1be32;
/* font sizes */
--root-font-size: 16px;
font-size: var(--root-font-size);
/* font-families */
--font-headline: "Roboto Mono", monospace;
--font-family: "Lato", sans-serif;
}
*,
*::after,
*::before {
box-sizing: border-box;
}
body {
background-color: var(--app-background-color);
color: var(--primary-color);
font-family: var(--font-family);
}
h1 {
font-size: 1.125rem;
line-height: 1.6;
}
h2 {
font-size: var(--root-font-size);
}
ul {
margin: 0;
}
.container {
margin-top: 10px;
display: flex;
flex-direction: column;
justify-content: center;
align-items: center;
row-gap: 5px;
}
.player,
.playlist {
width: 450px;
background-color: var(--background-color);
border: 3px solid var(--foreground-color);
}
.player {
height: 260px;
padding: 10px;
display: flex;
flex-direction: column;
align-items: center;
row-gap: 10px;
}
.player-bar,
.playlist-bar {
display: flex;
justify-content: space-between;
align-items: center;
padding: 0 5px;
width: 100%;
height: 30px;
background-color: var(--foreground-color);
}
.parallel-lines {
display: flex;
flex-wrap: wrap;
row-gap: 6px;
padding: 0 5px;
}
.parallel-lines > div {
height: 2px;
width: 100%;
min-width: 75px;
background-color: var(--highlight-color);
}
.fcc-title,
.playlist-title {
color: var(--secondary-color);
margin: 0 10px;
font-family: var(--font-headline);
}
.player-content {
display: flex;
background-color: var(--foreground-color);
width: 430px;
height: 200px;
column-gap: 13px;
align-items: center;
justify-content: center;
}
#player-album-art {
background-color: var(--secondary-color);
border: 6px solid var(--background-color);
}
#player-album-art img {
width: 150px;
display: block;
}
.player-display {
display: flex;
flex-direction: column;
row-gap: 20px;
padding: 14px;
background-color: var(--background-color);
height: 153px;
width: 226px;
}
.player-display-song-artist {
height: 80px;
}
.player-buttons svg {
fill: var(--primary-color);
}
.playing > svg {
fill: var(--highlight-color);
}
.player-buttons {
display: flex;
justify-content: space-around;
}
button {
background: transparent;
border: none;
color: var(--primary-color);
cursor: pointer;
font-size: var(--root-font-size);
outline-color: var(--highlight-color);
text-align: center;
}
.playlist-song {
outline-color: var(--highlight-color);
}
.playlist li:not(:last-child) {
border-bottom: 1px solid var(--background-color);
}
button:focus,
.playlist-song:focus {
outline-style: dashed;
outline-width: 2px;
}
/* Playlist */
.playlist {
height: auto;
padding: 10px;
display: flex;
flex-direction: column;
align-items: center;
row-gap: 10px;
}
#playlist-songs {
width: 430px;
height: 100%;
background-color: var(--foreground-color);
display: flex;
flex-direction: column;
row-gap: 8px;
padding: 8px 9px;
visibility: visible;
justify-content: start;
list-style: none;
}
.playlist-song {
display: flex;
height: 55px;
justify-content: space-between;
align-items: center;
padding: 5px;
}
[aria-current="true"] {
background-color: var(--background-color);
}
[aria-current="true"] p {
color: var(--highlight-color);
}
.playlist-song-info {
height: 100%;
display: flex;
flex-direction: row;
align-items: center;
justify-content: space-around;
column-gap: 7px;
padding: 5px 0;
font-family: var(--font-family);
}
#player-song-title,
#player-song-artist {
margin: 0;
}
#player-song-artist {
color: var(--highlight-color);
font-size: 0.75rem;
}
#player-song-title {
font-size: 1.125rem;
}
.playlist-song-title {
font-size: 0.85rem;
width: 241px;
text-align: left;
}
.playlist-song-artist {
font-size: 0.725rem;
width: 80px;
}
.playlist-song-duration {
font-size: 0.725rem;
margin: auto;
font-family: var(--font-headline);
width: 30px;
}
.playlist-song-delete {
padding: 0;
width: 20px;
height: 20px;
}
.playlist-song-delete,
.playlist-song-delete {
fill: var(--foreground-color);
}
.playlist-song-delete:hover circle,
.playlist-song-delete:focus circle {
fill: #ff0000;
}
@media (max-width: 700px) {
.player,
.playlist {
width: 300px;
}
.player {
height: 340px;
}
#playlist-songs {
height: 280px;
padding: 5px 6px;
overflow-y: scroll;
overflow-x: hidden;
scrollbar-color: var(--background-color) var(--secondary-color);
scrollbar-width: thin;
}
#playlist-songs::-webkit-scrollbar {
width: 5px;
}
#playlist-songs::-webkit-scrollbar-track {
background: var(--background-color);
}
#playlist-songs::-webkit-scrollbar-thumb {
background: var(--secondary-color);
}
h1 {
font-size: 0.813rem;
}
h2 {
font-size: 0.75rem;
}
.player-bar,
.playlist-bar,
.player-content,
#playlist-songs {
width: 280px;
}
.playlist-song {
justify-content: space-between;
}
.playlist-song-title {
width: 140px;
}
.playlist-song-artist {
width: 40px;
}
.playlist-song-duration > button {
padding: 0;
}
.player-content {
display: inline;
position: relative;
justify-items: center;
height: 100%;
}
#player-album-art {
z-index: -100;
height: 280px;
box-shadow: none;
background: #000;
}
#player-album-art img {
width: 100%;
opacity: 0.6;
}
.player-display-song-artist {
padding: 0 10px;
}
.player-display-song-artist > p {
white-space: pre-wrap;
}
.player-display {
position: absolute;
width: 100%;
z-index: 1000;
background-color: transparent;
top: 0;
height: 280px;
justify-content: space-between;
text-align: center;
}
}
```
```js
const playlistSongs = document.getElementById("playlist-songs");
const playButton = document.getElementById("play");
const pauseButton = document.getElementById("pause");
const nextButton = document.getElementById("next");
const previousButton = document.getElementById("previous");
const shuffleButton = document.getElementById("shuffle");
const allSongs = [
{
id: 0,
title: "Scratching The Surface",
artist: "Quincy Larson",
duration: "4:25",
src: "https://cdn.freecodecamp.org/curriculum/js-music-player/scratching-the-surface.mp3",
},
{
id: 1,
title: "Can't Stay Down",
artist: "Quincy Larson",
duration: "4:15",
src: "https://cdn.freecodecamp.org/curriculum/js-music-player/can't-stay-down.mp3",
},
{
id: 2,
title: "Still Learning",
artist: "Quincy Larson",
duration: "3:51",
src: "https://cdn.freecodecamp.org/curriculum/js-music-player/still-learning.mp3",
},
{
id: 3,
title: "Cruising for a Musing",
artist: "Quincy Larson",
duration: "3:34",
src: "https://cdn.freecodecamp.org/curriculum/js-music-player/cruising-for-a-musing.mp3",
},
{
id: 4,
title: "Never Not Favored",
artist: "Quincy Larson",
duration: "3:35",
src: "https://cdn.freecodecamp.org/curriculum/js-music-player/never-not-favored.mp3",
},
{
id: 5,
title: "From the Ground Up",
artist: "Quincy Larson",
duration: "3:12",
src: "https://cdn.freecodecamp.org/curriculum/js-music-player/from-the-ground-up.mp3",
},
{
id: 6,
title: "Walking on Air",
artist: "Quincy Larson",
duration: "3:25",
src: "https://cdn.freecodecamp.org/curriculum/js-music-player/walking-on-air.mp3",
},
{
id: 7,
title: "Can't Stop Me. Can't Even Slow Me Down.",
artist: "Quincy Larson",
duration: "3:52",
src: "https://cdn.freecodecamp.org/curriculum/js-music-player/cant-stop-me-cant-even-slow-me-down.mp3",
},
{
id: 8,
title: "The Surest Way Out is Through",
artist: "Quincy Larson",
duration: "3:10",
src: "https://cdn.freecodecamp.org/curriculum/js-music-player/the-surest-way-out-is-through.mp3",
},
{
id: 9,
title: "Chasing That Feeling",
artist: "Quincy Larson",
duration: "2:43",
src: "https://cdn.freecodecamp.org/curriculum/js-music-player/chasing-that-feeling.mp3",
},
];
const audio = new Audio();
let userData = {
songs: [...allSongs],
currentSong: null,
songCurrentTime: 0,
};
const renderSongs = (array) => {
const songsHTML = array
.map((song)=> {
return `
${song.title}
${song.artist}
${song.duration}
`;
})
.join("");
playlistSongs.innerHTML = songsHTML;
};
const sortSongs = () => {
--fcc-editable-region--
userData?.songs.sort((a,b) => {
});
--fcc-editable-region--
};
renderSongs(userData?.songs);
```
