The loop works only once and then nothing happens. I have three testimonials, and can go only once forward or backwords.Thanks for help!
const nextBtn = document.querySelector(".next-btn");
const prevBtn = document.querySelector(".prev-btn");
const testimonials = document.querySelectorAll(".testimonial");
let index = 0;
window.addEventListener("DOMContentLoaded", function () {
show(index);
});
function show(index) {
testimonials.forEach((testimonial) => {
testimonial.style.display = "none";
});
testimonials[index].style.display = "flex";
}
nextBtn.addEventListener("click", function () {
index++;
if (index > testimonials.length - 1) {
index = 0;
}
show(index);
});
prevBtn.addEventListener("click", function () {
index--;
if (index < 0) {
index = testimonials.length - 1;
}
show(index);
});
I would use a "hidden" class to hide the non-active testimonials instead of manipulating the element's style in-line. Also, your navigation logic can be simplified to a modulo operation.
The code your originally posted seemed to work out well, but it seems to cluttered with redundancy (code reuse). It also lacks structural flow (readability).
const
modulo = (n, m) => (m + n) % m,
moduloWithOffset = (n, m, o) => modulo(n + o, m);
const
nextBtn = document.querySelector('.next-btn'),
prevBtn = document.querySelector('.prev-btn'),
testimonials = document.querySelectorAll('.testimonial');
let index = 0;
const show = (index) => {
testimonials.forEach((testimonial, currIndex) => {
testimonial.classList.toggle('hidden', currIndex !== index)
});
}
const navigate = (amount) => {
index = moduloWithOffset(index, testimonials.length, amount);
show(index);
}
// Create handlers
const onLoad = (e) => show(index);
const onPrevClick = (e) => navigate(-1);
const onNextClick = (e) => navigate(1);
// Add handlers
window.addEventListener('DOMContentLoaded', onLoad);
nextBtn.addEventListener('click', onNextClick);
prevBtn.addEventListener('click', onPrevClick);.testimonial {
display: flex;
}
.testimonial.hidden {
display: none;
}<div>
<button class="prev-btn">Prev</button>
<button class="next-btn">Next</button>
</div>
<div>
<div class="testimonial">A</div>
<div class="testimonial">B</div>
<div class="testimonial">C</div>
<div class="testimonial">D</div>
<div class="testimonial">E</div>
<div class="testimonial">F</div>
</div>