Plugin structure
- Flutter course
- Expert
- Lesson 16/39
- 4 min
Learn the Dart and native parts of a Flutter plugin.
Plugin structure
A Flutter plugin consists of two sides: the Dart side talks to the app, the native side (Android/iOS) communicates with the system. The two sides are connected via a MethodChannel.
// lib/my_plugin.dart
class MyPlugin {
static const _channel = MethodChannel('my_plugin');
static Future<String> getVersion() async {
return await _channel.invokeMethod('getVersion');
}
}MethodChannel bridge
MethodChannel is the bridge between Dart and native. Dart sends a message to native with invokeMethod, and native replies via MethodCall. The channel name must be the same on both sides.
Practice MyPlugin Dart class
Define a class named MyPlugin. Set static const _channel = MethodChannel('my_plugin'). The static Future<String> getVersion() async method should return _channel.invokeMethod('getVersion'). In main, print MyPlugin.
Starter code
import 'package:flutter/services.dart';
// MyPlugin sınıfını tanımla
// static const _channel'a 'my_plugin' adlı MethodChannel ata
// version getiren bir static async metod yaz (invokeMethod ile)
void main() {
// MyPlugin yazdır
}Sample solution
import 'package:flutter/services.dart';
class MyPlugin {
static const _channel = MethodChannel('my_plugin');
static Future<String> getVersion() async {
return await _channel.invokeMethod('getVersion');
}
}
void main() {
print(MyPlugin);
}Expected output
MyPlugin
Questions and answers
Review the lesson questions together with their answers. To test yourself, solve the lesson interactively.
1 Which two sides does a Flutter plugin consist of?
- Frontend and backend
- iOS and only iOS
- Dart and native Correct answer
- Web and mobile
Explanation: The plugin's Dart side talks to the app, the native side (Android/iOS) talks to the system; the two are bridged via MethodChannel.
2 Create a MethodChannel
static const _channel = ____('my_plugin');static const _channel = MethodChannel('my_plugin');Explanation: MethodChannel is used for Dart-native method calls; EventChannel is for streams, BasicMessageChannel for low-level messages, and BinaryMessenger is the transport layer.
3 Plugin structure matches
| Term | Meaning |
|---|---|
plugin |
Two-sided package |
Dart |
App side |
native |
System side |
MethodChannel |
Bridge |