How can I write Platform specific code in a Flutter package? - flutter

I have a code, which I want to make available as a pub or a package to other Flutter projects. But this code makes use of some native android code in Kotlin.
In a Flutter application, we have both iOS and Android folders, so we can easily write native code there. But in case of a plugin or a package, there are no iOS and Android folders, so I'm confused how can we implement native code in a package.

Related

How to add dependencies to Flutter plugin

I'm trying to implement new Flutter plugin to wrap my native SDKs and use my native SDK directly and return the result.
I already finished the Android part by adding my library using maven and use it inside my Android module, but now I'm stuck on iOS part as the plugin code is just a pod that will be used at the end so how I can add my dependence via Swift Package Manager to the plugin pod and use it instead of going and add vendor frameworks. Is there any way to do that?
Currently you likely need to switch to CocoaPods.
Flutter does not support Swift Package Manager. See https://github.com/flutter/flutter/issues/33850

Is it possible to get flutter SDK version during application runtime?

I'm using fvm, so multiple flutter SDK versions are installed and I want to be able to get, if possible, flutter SDK version during application runtime to verify that correct version was used during build, for example, when I compile manually in Xcode.

New Flutter Project on Android Studio

Can you guys tell me what all these different projects means?
New Flutter Project
Because I can't find the documentation anywhere
So if you can find the reference it will help me
Flutter Application: A fully-functional standalone Flutter application.
Flutter Plugin: A plugin is a kind of bridge that you develop between a native feature like camera API in Android and iOS.
Flutter Package: A package is a flutter application written solely using Dart. It doesn't have much to do with the Native functionalities.
Flutter Module: A module is a set of functionalities that you want to use in your app. It is a custom code that does a specific task but can be used for other apps in the future. So, you keep it handy. In other words, this module can be integrated in other apps too.

What is the difference between flutter plugin and flutter module?

I am new to flutter plugin development, I have read Developing packages & plugins and Writing a good Flutter plugin, but I am confused as a beginner, I have developed Flutter Application based on webview_flutter and a JavaScript library to work offline. I want to extend it as a module or a plugin.
Webview renders some stuff.
JavaScript library is being attached from assets.
I am not calling any Platform API directly from my code but my code depends on another plugin.
How do I proceed this? As a plugin or as a module?
A plugin is about making native functionality available to Flutter.
A module is about integrating Flutter with an existing native application.
Perhaps what you actually want is a reusable Pub package that you can publish to pub.dartlang.org (a plugin is also a Pub package, just a special one that additionally utilizes access to the native platform)
See also
https://flutter.io/docs/development/packages-and-plugins/developing-packages
https://www.dartlang.org/guides/libraries/create-library-packages
A "library package" is a Pub package in contrary to a plain Dart "application package" which is usually not published to pub.dartlang.org.
A pure Dart Pub package (library package) that does not depend on dart:html, dart:ui (Flutter) and is not a Flutter plugin, can be used on any platform (server, command line, Flutter, browser).
If your package has one of the named dependencies, it is limited to a specific platform.
pub.dartlang.org shows labels to categorize published packages accordingly (FLUTTER,WEB,OTHER)
Flutter plugins:
In short: Native related developments.
Flutter plugin is the wrapper of the native code like android( Kotlin or java) and iOS(swift or objective c). ... Flutter can do anything that a native application can through the use of Platform Channels and Message Passing. Flutter instructs the native iOS/Android code to perform an action and returns the result to Dart.
Flutter packages or modules:
In short: Make the development faster by using code from util libraries.
Flutter supports using shared packages contributed by other developers to the Flutter and Dart ecosystems. This allows quickly building an app without having to develop everything from scratch.

Can I create a library like a cocoapod or framework file for iOS or an aar file or gradle dependency for Android with Flutter?

I have a library our partners use to drop our UI and flow into their apps. Can I make a cocoapod or framework file or an aar file or gradle dependency with a flutter project?
Yes! For general information, see https://flutter.dev/docs/development/add-to-app
To create an AAR from a Flutter module that other Android apps can use without any direct dependency on Flutter, see Option A - Depend on the Android Archive (AAR)
To create a Framework from a Flutter module that other iOS apps can use without any direct dependency on Flutter, see Option B - Embed frameworks in Xcode
You can also find samples at
https://github.com/flutter/samples/tree/master/experimental/add_to_app, refer to the respective samples: android_using_prebuilt_module and ios_using_prebuilt_module
Now, if you are talking about integrating Flutter into an existing library (AAR or Framwork), then no, this is currently not supported, but is being explored:
https://github.com/flutter/flutter/issues/39027
note that this would be termed “add-to-library” as opposed to "add-to-app"
also mentioned, flutter/add-to-app:
Packing a Flutter library into another sharable library or packing multiple Flutter libraries into an application isn’t supported.