Last updated
Aug 5, 2024
8 mins read
Share on
Build 10x products in minutes by chatting with AI - beyond just a prototype.
Software Development Executive - II
A Flutter and iOS developer with 3+ years of experience. Looking forward to each new thing in tech. Wandering like Alice.
Software Development Executive - II
A Software Engineer passionate about crafting seamless mobile apps. Fueled by chai, transforming ideas into code with every sip. A lover of clean architecture, open-source, and late-night debugging marathons, blending creativity and tech to build solutions that make a difference.
If you've delved into the app development world, you certainly would have noticed the buzz around Flutter. Flutter, Google's open-source UI toolkit, is changing the game by enabling developers to create beautiful native mobile, web, and desktop applications using a single codebase. An essential part of this cross-platform solution is platform integration. Without thorough platform integration, a Flutter app would feel just as out of place as a fish on a bicycle.
Platform integration in Flutter allows developers to connect their app with its native services and APIs, such as GPS, sensors, and more. This often involves writing platform-specific code to tap into services that Flutter alone cannot access or are better handled by the native platform. A well-integrated Flutter app becomes as native as any other app developed using platform-specific code.
Platform integration may sound daunting, but thanks to Flutter’s intuitive architecture, it can be broken down into manageable concepts.
In essence, Platform Integration refers to the interaction of a Flutter app with the native features and services of the device's operating system. For instance, accessing the device camera, sending push notifications, reading device contacts, GPS, sensors, and similar tasks are made possible with platform integration.
Diving deeper, we use platform-specific code to leverage these native capabilities. The platform-specific code allows Flutter, a Dart-based framework, to communicate efficiently with native iOS or Android code. Throughout this process, platform integration develops channels for your Flutter app, like a well-constructed network of roads connecting different cities. This organized set of channels is known as platform channels.
With platform channels, your Flutter app can smoothly drive the native code's functionalities, taking your app’s user experience to the next level. However, to run this operation smoothly, we need well-defined platform channels for transmitting and receiving messages between the Flutter app and the native code.
The uniqueness of the Flutter toolkit lies in its Dart language foundation, allowing for single codebase app development. But even as Google stacked Dart with a comprehensive range of features, some platform-specific functionalities are left best to the native ecosystems. This necessity calls for platform-specific code.
Platform-specific code is nothing but native code that you write to tap into specific operating system resources that your Flutter app is running on. This native code could be Java/Kotlin for Android or Swift/Objective-C for iOS. Why not have Flutter equipped to handle every possible functionality instead?
The reason is the dynamic nature of native ecosystems. Android and iOS regularly update their APIs, add new features, and sometimes deprecate old ones. By allowing platform-specific code, Flutter allows developers to stay at the top of these changes, unburdening itself from the enormous task of maintaining up-to-date APIs.
As a result, you can adopt newer APIs and functionalities as they roll out, allowing you to stand out and deliver unique features to your end users. Platform-specific code becomes your magic wand, enabling every possibility, from tapping into new sensors to using the latest security protocols.
Now that we understand the significance of platform-specific code in a Flutter app, let's dig deeper into how a Flutter app communicates with the native code to perform these operations. The established communication mechanism is fulfilled through platform channels.
Platform channels act as a bridge that aids in synchronous and asynchronous message passing between your Flutter app and the native platform. It connects the Flutter code and the native code, enabling your features to run smoothly across the multiple platforms your app supports. It's a communication channel between the Dart code (Flutter side) and the native code through method calls.
Flutter supports three types of channels, MethodChannel, EventChannel, and BasicMessageChannel, each designed to support different types of data communication scenarios with the native code. With the help of these respective channels, a Flutter app can send messages, receive responses, and listen to events from the native side.
Understanding these platform channels and platform-specific code forms the crux of efficient platform integration and unlocks the potential for outstanding Flutter apps that can leverage platform-specific functionalities and APIs to the maximum.
Implementing platform channels might sound complex, but Flutter makes it relatively straightforward. The idea is to define a common channel (a MethodChannel, for instance) for your Flutter and platform-specific codes. This channel becomes responsible for passing messages back and forth.
The following steps give a brief idea of the process:
Start by defining a unique MethodChannel in your Flutter app.
Define a corresponding MethodChannel with the same channel name on your platform-specific code.
The Flutter code can now use this channel to invoke methods available on this channel.
In your platform-specific code, listen for these method calls on this MethodChannel and respond accordingly.
Adding some native code snippets to your Flutter project does not make it any less Flutter. On the contrary, it only starts to separate your app from the rest by enabling it to offer platform-specific features. This way, your app remains responsive and immediate, ensuring your users have the best experience no matter what device they use.
We've examined Platfom Integration and how to use Platform Channels effectively in a Flutter App. Let's now delve into the core element that allows this communication to happen seamlessly - the Flutter Platform Client.
The Flutter Platform Client acts as a mediator between the Native Code and the Flutter Code. The Flutter Platform Client connects the two ends - Flutter app (Dart Code) and the Native APIs. Here's where the platform-specific method calls are made and responses are received.
The platform-specific code defined at the Flutter Platform Client ensures that the corresponding native code is activated whenever a method call is made from the Dart side. In return, it diligently receives the native responses and returns them to the Flutter code.
Through this process, the platform client upholds the architecture's sanctity while efficiently passing the necessary data between the Dart and Native side. By enabling this, the Flutter Platform Client forms an integral part of Platform Integration, ensuring that your Flutter apps can utilize the benefits of native APIs while maintaining their cross-platform nature.
Understanding the nuts and bolts of Platform Integration and how to use Flutter Platform Client and Platform Channels sets a sound groundwork for your Flutter App development. Now, let's review the platforms that support Flutter Platform Integration.
Flutter, backed by Google, was initially designed keeping mobile application development in mind. Hence, Android and iOS are well-supported platforms for Flutter integration. But, with the power of platform-specific code and platform channels, Flutter's capabilities continue beyond there.
Over time, Flutter's relevance has rapidly spread across various platforms. It is now used for web application development, desktop application development (for Mac, Windows, and Linux), and even embedded systems. Imagine writing a platform-specific code in your Flutter App that can potentially rotate a car's tires!
While platform integration support for these platforms is still under work, there have been promising developments. For instance, you can now run platform-specific Dart code on the Web, and early-stage desktop support is available on the Flutter master channel.
Irrespective of the platform, the common denominator for making platform integration possible is the ability to write native code in the respective platforms' preferred languages – Kotlin/Java for Android, Swift/Objective-C for iOS, JavaScript for web, and so on.
To make our discussion more relatable, let's overview a real-world example that successfully used Flutter platform integration. Consider a Flutter app responsible for reporting the battery level of a mobile.
In this app, Flutter’s MethodChannel was used to establish a connection between the Dart side and the native side. A channel was created with a specific channel name on the Dart side. Correspondingly, on the native side (Android and iOS), channels are registered with the same channel name.
On the Dart side, the battery level was requested by calling a method ‘getBatteryLevel’ on this channel. Simultaneously, on the native side, a listener was set up for this channel to handle method calls.
Whenever ‘getBatteryLevel’ was invoked on the Dart side, the listener on the native side would trigger the corresponding native code - BatteryManager API on Android, and device.batteryLevel on iOS, which returned the battery level. This result was sent back to the Dart side through the MethodChannel and was displayed in the Flutter app.
With Flutter's rise in the app development world, Platform Integration represents a core attribute that underlines its popularity. Its role in smoothly translating Dart-based Flutter apps to the native platform while leveraging platform-specific features cannot be undermined.
In this post, we peeled back the layers of platform integration in Flutter - how platform-specific code translates into platform-specific functionalities, the power of platform channels, and the integral role of Flutter platform clients. We also examined a real-world example illustrating successful Flutter app platform integration.
The beauty of Flutter is that it offers you the canvas (Dart) to paint (write app) across multiple platforms, but it doesn't stop there. It goes beyond and allows you to choose your colors (platform-specific code) to paint your masterpiece (app).
