Flutter Web Speed Optimization and Removing the # from the URL

Flutter web offers a robust platform for building responsive web applications, but optimizing performance and ensuring clean URLs can enhance user experience. This article covers techniques to optimize Flutter web performance and remove the # (hash) from the URL.

1. Optimizing Flutter Web Performance

Web performance is critical for providing a smooth user experience. Below are some techniques to enhance the speed of your Flutter web application.

1.1 Preconnected and DNS Prefetching

Preconnected and DNS-prefetch help establish early connections to external resources, reducing latency when these resources are requested later.

<link rel="preconnect" >
<link rel="dns-prefetch" >        

1.2 Preloading Essential Scripts

Preload key resources like main.dart.js and flutter.js to ensure they load early in the page lifecycle.

<link rel="preload" href="main.dart.js" as="script">
<link rel="preload" href="flutter.js" as="script">        

1.3 Lazy Loading Non-Critical Assets

Only load critical assets initially. Defer loading of non-essential scripts until after the page has loaded, improving the initial load time.

1.4 Inline Critical CSS

Inlining critical CSS directly in the HTML minimizes the time it takes to render the first screen.

<style>
  body { margin: 0; font-family: Arial, sans-serif; background-color: #f4f4f4; }
/* Additional critical styles */
</style>        

1.5 Show a Loading Screen

Use a lightweight loading screen while the Flutter app is initializing, providing a better user experience during the loading phase.

<div id="loading">
  <div class="spinner"></div>
  <div id="loading-text">Loading your experience...</div>
</div>        

1.6 Minimize JavaScript Bundle Size

Reduce the size of your JavaScript bundle by tree-shaking and avoiding large dependencies. You can do this by:

• Analyzing the package sizes and removing unnecessary packages.
• Splitting code into smaller chunks that load only when necessary.

1.7 Efficiently Handle Images and Fonts

Optimize images and fonts by using formats like WebP for images and subsetting fonts to include only the required characters.

2. Removing the # from Flutter Web URL

By default, Flutter web apps use hash-based routing (/#/route). Removing the # from the URL makes it cleaner and more professional. Here’s how you can do it:

2.1 Using the UrlPathStrategy

In Flutter, you can remove the # by setting the URL strategy to PathUrlStrategy in your main.dart file:

import 'package:flutter/material.dart';
import 'package:flutter_web_plugins/flutter_web_plugins.dart';

void main() {
  setUrlStrategy(PathUrlStrategy());
  runApp(MyApp());
}        

2.2 Adding a base Tag in index.html

Ensure you add a <base> tag in your index.html to avoid broken links when the user navigates directly to a URL.

<base href="/">        

2.3 Configuring Web Server

Configure your web server to serve index.html for all routes. For instance, if you're using Apache, add the following in your .htaccess file:

<IfModule mod_rewrite.c>
  RewriteEngine On
  RewriteCond %{REQUEST_FILENAME} !-f
  RewriteCond %{REQUEST_FILENAME} !-d
  RewriteRule . /index.html [L]
</IfModule>        

For Nginx, use:

location / {
    try_files $uri $uri/ /index.html;
}        

Optimizing your Flutter web app for speed and removing the # from the URL will significantly improve user experience and professionalism. Implement these techniques to make your Flutter web apps load faster and have cleaner URLs, contributing to a more polished and efficient web application.

This article provides a comprehensive guide on optimizing Flutter web performance and cleaning up URLs. By applying these methods, you'll ensure that your web applications are both fast and user-friendly.

flutter build web --release