108 lines
2.0 KiB
Svelte
108 lines
2.0 KiB
Svelte
<script>
|
|
import { spring } from 'svelte/motion';
|
|
|
|
let count = 0;
|
|
|
|
const displayed_count = spring();
|
|
$: displayed_count.set(count);
|
|
$: offset = modulo($displayed_count, 1);
|
|
|
|
/**
|
|
* @param {number} n
|
|
* @param {number} m
|
|
*/
|
|
function modulo(n, m) {
|
|
// handle negative numbers
|
|
return ((n % m) + m) % m;
|
|
}
|
|
</script>
|
|
|
|
<div class="counter">
|
|
<button on:click={() => (count -= 1)} aria-label="Decrease the counter by one">
|
|
<svg aria-hidden="true" viewBox="0 0 1 1">
|
|
<path d="M0,0.5 L1,0.5" />
|
|
</svg>
|
|
</button>
|
|
|
|
<div class="counter-viewport">
|
|
<div class="counter-digits" style="transform: translate(0, {100 * offset}%)">
|
|
<strong class="hidden" aria-hidden="true">{Math.floor($displayed_count + 1)}</strong>
|
|
<strong>{Math.floor($displayed_count)}</strong>
|
|
</div>
|
|
</div>
|
|
|
|
<button on:click={() => (count += 1)} aria-label="Increase the counter by one">
|
|
<svg aria-hidden="true" viewBox="0 0 1 1">
|
|
<path d="M0,0.5 L1,0.5 M0.5,0 L0.5,1" />
|
|
</svg>
|
|
</button>
|
|
</div>
|
|
|
|
<style>
|
|
.counter {
|
|
display: flex;
|
|
border-top: 1px solid rgba(0, 0, 0, 0.1);
|
|
border-bottom: 1px solid rgba(0, 0, 0, 0.1);
|
|
margin: 1rem 0;
|
|
}
|
|
|
|
.counter button {
|
|
width: 2em;
|
|
padding: 0;
|
|
display: flex;
|
|
align-items: center;
|
|
justify-content: center;
|
|
border: 0;
|
|
background-color: transparent;
|
|
touch-action: manipulation;
|
|
color: var(--text-color);
|
|
font-size: 2rem;
|
|
}
|
|
|
|
.counter button:hover {
|
|
background-color: var(--secondary-color);
|
|
}
|
|
|
|
svg {
|
|
width: 25%;
|
|
height: 25%;
|
|
}
|
|
|
|
path {
|
|
vector-effect: non-scaling-stroke;
|
|
stroke-width: 2px;
|
|
stroke: var(--text-color);
|
|
}
|
|
|
|
.counter-viewport {
|
|
width: 8em;
|
|
height: 4em;
|
|
overflow: hidden;
|
|
text-align: center;
|
|
position: relative;
|
|
}
|
|
|
|
.counter-viewport strong {
|
|
position: absolute;
|
|
display: flex;
|
|
width: 100%;
|
|
height: 100%;
|
|
font-weight: 400;
|
|
color: var(--accent-color);
|
|
font-size: 4rem;
|
|
align-items: center;
|
|
justify-content: center;
|
|
}
|
|
|
|
.counter-digits {
|
|
position: absolute;
|
|
width: 100%;
|
|
height: 100%;
|
|
}
|
|
|
|
.hidden {
|
|
top: -100%;
|
|
user-select: none;
|
|
}
|
|
</style>
|