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How to Implement Infinite Scroll and Quick View in Shopify Using AJAX API

A seamless shopping experience often means faster browsing and fewer page reloads. Two key features that can dramatically improve your Shopify store's experience is infinite scroll and quick view.

Both features rely on the Shopify AJAX API, enabling dynamic content loading without requiring full-page refreshes. In this tutorial, we’ll explore how to implement both using JavaScript — enhancing your store’s speed, engagement, and conversion rates.

1. Why Infinite Scroll and Quick View Matter

Traditional pagination interrupts user flow, while pop-ups that load slowly can frustrate shoppers, and quick view helps solve these problems:

  • Infinite Scroll: Loads more products automatically as users reach the bottom of a collection page.
  • Quick View: Opens product details (price, images, variants) in a modal without leaving the current page.

These features create a smoother, app-like browsing experience that encourages users to explore for longer.

2. Prerequisites

Before starting, make sure you have:

  • A published Shopify Online Store 2.0 theme.
  • Access to edit your theme.liquid, collection.liquid, and JavaScript files.
  • Basic understanding of HTML, Liquid, and JavaScript

You don’t need any external libraries — everything is handled through Shopify’s native AJAX endpoints.

3. Setting Up Infinite Scroll

Infinite Scroll replaces pagination with automated product loading. Here’s how to add it safely.

Step 1: Add the Markup
Ensure your collection template wraps products in a parent container:

<div class="product-grid">
  {% for product in collection.products %}
    {% render 'product-card', product: product %}
  {% endfor %}
</div>
<div class="load-status">Loading more products…</div>
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The .product-grid class will be used to append new items dynamically.

Step 2: Create JavaScript Logic
Add this script to your theme’s main.js or a new file included in theme.liquid:

let currentPage = 1;
let loading = false;

window.addEventListener("scroll", () => {
  if (window.innerHeight + window.scrollY >= document.body.offsetHeight - 200) {
    if (!loading) {
      loading = true;
      loadMoreProducts();
    }
  }
});

function loadMoreProducts() {
  currentPage++;
  fetch(`${window.location.pathname}?page=${currentPage}`)
    .then(res => res.text())
    .then(html => {
      const parser = new DOMParser();
      const doc = parser.parseFromString(html, "text/html");
      const newProducts = doc.querySelectorAll(".product-grid .product-card");
      if (newProducts.length > 0) {
        document.querySelector(".product-grid").append(...newProducts);
        loading = false;
      } else {
        document.querySelector(".load-status").innerText = "No more products";
      }
    })
    .catch(err => console.error("Infinite scroll error:", err));
}
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This code detects when the user scrolls near the page bottom, requests the next product page, and appends new product cards seamlessly.

4. Implementing The Quick View Feature

Quick View allows shoppers to preview product details instantly without leaving the collection page.

Step 1: Add a Quick View Button
Inside your product-card.liquid snippet, include a trigger:

<button class="quick-view-btn" data-handle="{{ product.handle }}">
  Quick View
</button>
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Step 2: Create a Modal Structure
Place this near the footer of your theme:

<div class="quick-view-modal">
  <div class="modal-content">
    <span class="close-modal">&times;</span>
    <h3 class="quick-view-title"></h3>
    <img class="quick-view-image" src="" alt="">
    <p class="quick-view-price"></p>
    <button class="add-to-cart">Add to Cart</button>
  </div>
</div>
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Style it using CSS:

.quick-view-modal { display:none; position:fixed; inset:0; background:rgba(0,0,0,0.6); justify-content:center; align-items:center; }
.quick-view-modal.active { display:flex; }
.modal-content { background:#fff; padding:20px; border-radius:8px; width:90%; max-width:400px; }
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Step 3: Fetch Product Data via AJAX

Use Shopify’s product endpoint: /products/{handle}.js

document.querySelectorAll(".quick-view-btn").forEach(btn => {
  btn.addEventListener("click", () => {
    const handle = btn.dataset.handle;
    openQuickView(handle);
  });
});

function openQuickView(handle) {
  fetch(`/products/${handle}.js`)
    .then(res => res.json())
    .then(product => {
      document.querySelector(".quick-view-title").innerText = product.title;
      document.querySelector(".quick-view-image").src = product.images[0];
      document.querySelector(".quick-view-price").innerText = `$${(product.price / 100).toFixed(2)}`;
      document.querySelector(".quick-view-modal").classList.add("active");

      document.querySelector(".add-to-cart").onclick = () => addToCart(product.variants[0].id);
    })
    .catch(err => console.error("Quick view error:", err));
}

function addToCart(variantId) {
  fetch("/cart/add.js", {
    method: "POST",
    headers: { "Content-Type": "application/json" },
    body: JSON.stringify({ id: variantId, quantity: 1 })
  })
  .then(() => alert("Item added to cart!"))
  .catch(err => console.error("Add to cart error:", err));
}

document.querySelector(".close-modal").addEventListener("click", () => {
  document.querySelector(".quick-view-modal").classList.remove("active");
});
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This fetches the product JSON, updates modal content dynamically, and even supports instant “Add to Cart” functionality using the Shopify AJAX cart endpoint.

5. Performance Optimization Tips

  • Use Lazy Loading for Images: Defer image loading for new products to improve page speed.
  • Throttle Scroll Events: For large collections, wrap your scroll listener in a debounce function to avoid excessive API calls.
  • Cache Product Data: Save fetched products locally to minimize repeated API requests.
  • Prefetch Next Page: When users reach 70% of the page, start loading the next set in the background.

6. Error Handling and Testing

Always handle edge cases:

  • Network Failures: Display a retry button if fetching fails.
  • Empty Collections: Show a “No more products” message.
  • Accessibility: Ensure modals are keyboard-navigable and focus-trapped.

Use browser DevTools to verify that the AJAX requests are returning valid HTML and JSON. Also, test in incognito mode to check caching behavior and mobile responsiveness.

7. When to Involve Professionals

If you’re building advanced features or managing multiple themes, partnering with a Shopify Expert Agency can accelerate the process. Such teams specialize in performance optimization, dynamic storefronts, and complex AJAX-based customizations. They ensure your store remains fast, scalable, and compatible with Shopify’s latest APIs.

For store owners who want to implement infinite scrolling, quick view modals, or advanced AJAX carts but lack in-house expertise, it’s often best to Hire Shopify Developers. Experienced developers can create modular, maintainable scripts that integrate seamlessly with your existing theme and third-party apps.

8. Conclusion

With the Shopify AJAX API, you can build highly interactive features like Infinite Scroll and Quick View without relying on external plugins. These techniques make product browsing faster and smoother — a must for modern eCommerce stores.

By combining asynchronous data fetching, dynamic DOM rendering, and clean user interface design, you’ll significantly improve engagement and reduce friction during shopping.

Once implemented, test performance across mobile and desktop, monitor analytics for bounce rate improvements, and continuously refine. If executed properly, these features can turn a standard Shopify store into a polished, app-like experience that customers love.

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