JSFiddle - React, Tailwind, and code Playground
[ASSIGNMENT] Close Frontend Application Quiz
by touqeer_shakeel
HTML
<script src="https://unpkg.com/react@16/umd/react.development.js"></script>
<script src="https://unpkg.com/react-dom@16/umd/react-dom.development.js"></script>
<div id="root"></div>
CSS
.List {
margin: 16px;
display: grid;
grid-template-columns: repeat(auto-fill, minmax(150px, 1fr));
grid-auto-rows: 60px;
grid-gap: 16px;
}
.List__item {
line-height: 60px;
text-align: center;
color: white;
text-shadow: 1px 1px rgba(0, 0, 0, 0.5);
box-shadow: 0px 1px 1px 0px rgba(0, 0, 0, 0.05);
}
/* Taken from https://clrs.cc/ */
.List__item--navy {
background-color: #001f3f;
}
.List__item--blue {
background-color: #0074d9;
}
.List__item--aqua {
background-color: #7fdbff;
}
.List__item--teal {
background-color: #39cccc;
}
.List__item--olive {
background-color: #3d9970;
}
.List__item--green {
background-color: #2ecc40;
}
.List__item--lime {
background-color: #01ff70;
}
.List__item--yellow {
background-color: #ffdc00;
}
.List__item--orange {
background-color: #ff851b;
}
.List__item--red {
background-color: #ff4136;
}
.List__item--maroon {
background-color: #85144b;
}
.List__item--fuchsia {
background-color: #f012be;
}
.List__item--purple {
background-color: #b10dc9;
}
.List__item--black {
background-color: #111111;
}
.List__item--gray {
background-color: #aaaaaa;
}
.List__item--silver {
background-color: #dddddd;
}
.List__item--selected {
border: 3px solid red;
}
.SelectedItems {
list-style: decimal;
margin: 16px;
display: grid;
grid-template-columns: repeat(auto-fill, minmax(150px, 1fr));
grid-auto-rows: 20px;
grid-gap: 8px;
}
React
const { Fragment, useState, useCallback, useMemo } = React;
// Implement a feature to allow item selection with the following requirements:
// 1. Clicking an item selects/unselects it.
// 2. Multiple items can be selected at a time.
// 3. Make sure to avoid unnecessary re-renders of each list item in the big list (performance).
// 4. Currently selected items should be visually highlighted.
// 5. Currently selected items' names should be shown at the top of the page.
//
// Feel free to change the component structure at will.
const List = React.memo(({ items }) => {
const [selectedItems, setSelectedItems] = useState([]);
const handleItemClick = useCallback(
(item) => {
if (selectedItems.includes(item)) {
setSelectedItems(selectedItems.filter((selectedItem) => selectedItem !== item));
} else {
setSelectedItems([...selectedItems, item]);
}
},
[selectedItems]
);
const isItemSelected = useCallback((item) => selectedItems.includes(item), [selectedItems]);
const selectedItemsMemo = useMemo(
() =>
selectedItems.map((item) => (
<li key={item.name} className={`SelectedItems__item SelectedItems__item--${item.color}`}>
{item.name}
</li>
)),
[selectedItems]
);
const listItemsMemo = useMemo(
() =>
items.map((item) => (
<li
key={item.name}
className={`List__item List__item--${item.color} ${isItemSelected(item) ? 'List__item--selected' : ''}`}
onClick={() => handleItemClick(item)}
>
{item.name}
</li>
)),
[items, isItemSelected, handleItemClick]
);
return (
<Fragment>
<ol className="List SelectedItems">{selectedItemsMemo}</ol>
<ul className="List">{listItemsMemo}</ul>
</Fragment>
);
});
// ---------------------------------------
// Do NOT change anything below this line.
// ---------------------------------------
const sizes = ['tiny', 'small', 'medium',...