SwiperJS Navigation not showing

Solution 1:

nextEl / prevEl :String with CSS selector or HTML element of the element that will work like "next/prev" button after click on it. https://swiperjs.com/swiper-api#navigation

Mistakes in your code:

1/2. The value should be a string

JavaScript Strings variables are written inside double or single quotes.

Correct:

nextEl: '.swiper-button-next',

Wrong:

nextEl: .swiper-button-next,

2/2. The string represent CSSSelector -or- HTMLElement (Selectors)

This is not appendChild behavior. Use class -or- id -or- data attribute or html-element selector.

Correct Examples:

2.1: Select by class:

 navigation={
    nextEl: `.some_class_selector`,
 }

2.2: By id:

 navigation={
    nextEl: `#next_btn`,
 }

2.3: By attribute:

 navigation={
    nextEl: `[data-next-btn]`,
 }

2.4: By HTML element (Less usefull):

 navigation={
    nextEl: `hgroup`,
 }

Your html:

<hgroup id="next-btn" class="some_class_selector" data-next-btn>next</hgroup>

As react props:

navigation={{
   prevEl: ".some_class_prev_selector",
   nextEl: ".some_class_next_selector"
}}

Wrong (The code below will not add <div>next</div> node to the DOM):

 navigation={
    nextEl: `<div>next</div>`, /* not appendChild*/
 }

SUM: "hello world" demo

**No way to show react Demo because swiper react available only as NPM

• Step 1: Add next/prev buttons nodes to the DOM.

• Step 2: Select the next/prev nodes.

<!-- Initialize Swiper -->
const swiper = new Swiper('.swiper-container', {
  loop: true,
  navigation: {
    nextEl: '.custom_next_btn',
    prevEl: '.custom_prev_btn',
  },
});

html,
body {
  position: relative;
  height: 100%;
}

body {
  background: #eee;
  font-family: Helvetica Neue, Helvetica, Arial, sans-serif;
  font-size: 14px;
  color: #000;
  margin: 0;
  padding: 0;
}

.swiper-container {
  width: 100%;
  height: 100%;
}

.swiper-slide {
  text-align: center;
  font-size: 18px;
  background: #fff;
  /* Center slide text vertically */
  display: flex;
  justify-content: center;
  align-items: center;
}

<link rel="stylesheet" href="https://unpkg.com/swiper/swiper-bundle.min.css">

<button class="custom_prev_btn">Custom Prev</button>
<button class="custom_next_btn">Custom Next</button>

<!-- Swiper -->
<div class="swiper-container">
  <div class="swiper-wrapper">
    <div class="swiper-slide">Slide 1</div>
    <div class="swiper-slide">Slide 2</div>
    <div class="swiper-slide">Slide 3</div>
    <div class="swiper-slide">Slide 4</div>
  </div>
</div>


<script src="https://unpkg.com/swiper/swiper-bundle.min.js"></script>

React code example:

/* index.js */
import React from "react";
import "./style.css";

// import Swiper core and required modules
import SwiperCore, { Navigation, Pagination, Scrollbar, A11y } from "swiper";

import { Swiper, SwiperSlide } from "swiper/react";
// Import Swiper styles
import "swiper/swiper.scss";
import "swiper/components/navigation/navigation.scss";
import "swiper/components/pagination/pagination.scss";
import "swiper/components/scrollbar/scrollbar.scss";

// install Swiper modules
SwiperCore.use([Navigation, Pagination, Scrollbar, A11y]);

export default function App() {
  return (
    <div>
      <button class="custom_next">Custom Next Btn</button>
      <button class="custom_prev">Custom Next Btn</button>
      <Swiper
        spaceBetween={50}
        slidesPerView={3}
        navigation={{
          nextEl: ".custom_next",
          prevEl: ".custom_prev"
        }}
      >
        <SwiperSlide>Slide 1</SwiperSlide>
        <SwiperSlide>Slide 2</SwiperSlide>
        <SwiperSlide>Slide 3</SwiperSlide>
        <SwiperSlide>Slide 4</SwiperSlide>
      </Swiper>
    </div>
  );
}