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How to Implement Infinite Scroll in Flutter for Scalable Business Apps

Sukhrob Djumaev


July 19, 2024

Who says programming isn't creative? I love creating magical experiences in apps that surprise and engage users. But with over 2 million apps in mobile stores, standing out is a real challenge.

How do I create something unique and captivating? The answer lies in the awesome tools provided by Flutter. Previously, I talked about Flutter's magical animations, and today, I'll share how to make your app's content easily accessible with smooth and fast infinite scrolling.

Why Use Infinite Scrolling?

Imagine scrolling through your social media feed or an online store catalog without ever hitting a "next page" button. That's the magic of infinite scrolling—it keeps the content coming as you scroll, making the experience seamless and engaging.

  • Users can just keep scrolling without any fuss, making the app a total joy to use.
  • Content loads in bite-sized chunks, cutting down initial load times and supercharging overall performance.
  • Users see more content in one go, boosting the chances they'll interact with it.
  • Content loads based on what users do, keeping the app lively and engaging.
  • On mobile, infinite scrolling maximizes the limited screen space perfectly.
Why Infinite Scrolling is Essential for User Engagement and App Performance

There are loads of other reasons why Flutter rocks for building data-heavy apps. Get the lowdown in this article: Why Choose Flutter for Mobile App Development.

When to Use Infinite Scrolling in Your Business App

Infinite scrolling is an amazing feature that can elevate the user experience and handle large datasets with ease. But, it’s not a one-size-fits-all solution—it truly shines in specific scenarios. Let’s dive into when and why you should use this technique to get the most out of it.

Large Volume of Dynamic Content

Apps like Facebook, Instagram, and Twitter are constantly buzzing with new content, updating every second. Infinite scrolling is a game-changer here, letting users scroll smoothly through hundreds or even thousands of updates without any interruptions. If your app continuously adds new posts, photos, or videos, infinite scrolling is a perfect fit. It keeps the experience fluid and engaging, allowing users to stay in the flow and enjoy the content without hitting any barriers.

Content-Heavy Platforms

Sites or apps where users dive into a lot of content all at once, like news apps, blogs, or media sites such as BuzzFeed or Medium, are perfect for infinite scrolling. These platforms host hundreds of articles, videos, or posts that users want to explore seamlessly without interruptions.

E-commerce Stores

Online stores with extensive product catalogs, like Amazon or eBay, benefit greatly from infinite scrolling. This technique is effective for displaying large inventories, typically starting from hundreds of items, making browsing smooth and encouraging more purchases.

Photo and Video Galleries

Platforms showcasing a large number of visual content, such as Pinterest or YouTube, thrive with infinite scrolling. It allows users to effortlessly scroll through hundreds or thousands of images or videos, enhancing the browsing experience and keeping users engaged longer.

When to Implement Infinite Scrolling in Your Business App for Best Results

Real-Time Data Applications

Apps providing live updates and real-time information, like stock market apps or live sports scores, are ideal candidates for infinite scrolling. This feature is beneficial for apps where data points are frequently updated, ensuring users get the latest information instantly without refreshing or navigating to new pages.

If your app handles various data types, Flutter is still a top pick. We've compared it with another popular platform in this article: Flutter vs. Ionic in 2023: Which is Best for Your App.

How to Implement Infinite Scroll in Flutter for Efficient Data Loading

Studies show that 53% of mobile users bail if a site or app takes over 3 seconds to load. But apps with smooth data loading can boost content consumption by 20%.

So, this tutorial will help you dodge the first stat and hit that sweet +20% boost in no time.

Implementation Overview

We'll use the tmdb_api package to fetch movie data and flutter_bloc for state management.

First, you need to get an API key from TMDB. Follow the instructions on their website to obtain your key.

Here's the implementation of the MoviesBloc:

In this code, we define a MoviesBloc that fetches movie data and handles loading more data when requested.

Using Bloc Transformers for Efficient Data Fetching

To efficiently manage API calls and ensure smooth scrolling, we employed a custom Bloc transformer. Transformers in Bloc help control the flow of events, allowing us to implement patterns like throttling and debouncing.

Why Use Transformers?

When implementing infinite scroll, there's a risk of making too many API calls, especially if the user scrolls rapidly. This can lead to performance issues and hitting rate limits on the API. By using a transformer, we can control the frequency of these calls, ensuring our application remains responsive and within API limits.

Throttling with throttleDroppable

In our MoviesBloc, we used a custom transformer called throttleDroppable. This transformer combines throttling with the droppable pattern. Throttling ensures that events are processed at most once in a specified duration, while the droppable pattern ensures that only the latest event is processed, dropping any intermediate events.

Here’s the implementation:

Infinite Scroll Widget

Next, let's create a widget to display the movie list and handle infinite scrolling:

To display our movie list, we use the ListView.separated widget in Flutter. This widget is particularly beneficial for handling large data sets due to its efficient memory management. ListView.separated only keeps the widgets visible on the screen in memory, along with a few that are just outside the viewport. This significantly reduces the memory footprint compared to keeping all list items in memory.

Items are built lazily, meaning that the widget only builds the items that are visible or near the visible area, which improves performance and responsiveness.

To handle infinite scrolling, we use a custom widget called InfiniteListPagination. This widget is responsible for detecting when the user has scrolled to the end of the list and then triggering a function to load more data.

The widget listens to the scroll events of the ScrollController and determines when the user has reached the maximum scroll extent. It uses a configurable threshold to determine when to start loading more data, providing flexibility in how early the loading starts.

Handling large data sets efficiently in Flutter can significantly enhance the user experience. By implementing infinite scroll with flutter_bloc and a custom InfiniteListPagination widget, you can ensure smooth and responsive data loading. Leveraging transformers in Bloc for controlled event processing and using ListView.separated for efficient memory management further optimizes performance.

This approach can be adapted to various data sources and use cases, making it a valuable technique for any Flutter developer. By following these strategies, you can build applications that handle large amounts of data gracefully, providing a seamless and enjoyable experience for your users.

Full code is available at:

Future Trends in App Development

Today, with the new capabilities of AI, I wouldn't just stop at smooth scrolling. AI and machine learning can supercharge it! AI can analyze what users like and load content they'll love. Platforms like Instagram and Facebook already do this, keeping users hooked by showing content based on their likes and behavior.

Moreover, pairing infinite scrolling with AR and VR is a game-changer. Imagine scrolling endlessly in VR, exploring products or art in a 3D space. Or an AR app that displays tons of info just by pointing at a product, no clicks needed. This makes the experience interactive and massively boosts engagement. For instance, Meta's Quest Pro uses mixed reality to integrate real-world environments with digital objects, enhancing user immersion. Companies like Boeing and Porsche are already leveraging AR for tasks such as assembly and maintenance, highlighting its practical applications in industry settings.

For insights on safeguarding user data during app updates, don't miss our article on How to Protect User Data When Updating Apps with Flutter.

Boost Your Business App with Infinite Scrolling and Expert Flutter Development

Infinite scrolling, powered by AI, AR, and VR, can transform your app's user experience. But to leverage these advanced features effectively, you need a team that truly knows their stuff.

At Ptolemay, our Flutter experts each have over 5 years of experience in their specialized fields. We excel in integrating cutting-edge technologies to make your app stand out.

Ready to elevate your app? Contact the gurus at Ptolemay. Let’s build something amazing together.