iOS ve Android için Özel Platform Eklentileri Yazma
Yerel Kotlin ve Swift API'lerini Dart'a açan federatif eklentiler yazın.
iOS ve Android için Özel Platform Eklentileri Yazma, CoddyKit'te ücretsiz bir Flutter Mobile Development dersidir. Bu, 4 dersinin 3. dersidir. Aşağıdan dersin tamamını ücretsiz okuyabilir, sonra tarayıcıda yerleşik kod editörü ve 7/24 yapay zeka koçu ile uygulamalı olarak pratik yapabilirsin. Bu, Flutter Mobile Development öğrenme yolunun bir parçasıdır ve ilerlemeniz web ve CoddyKit uygulaması arasında senkronize olur. Flutter Mobile Development kursu toplamda 4 dersten oluşur.
Bu dersin bazı bölümleri henüz çevrilmemiş olup İngilizce olarak gösterilmektedir.
Why Platform Plugins?
Dart cannot call native iOS or Android APIs directly. A platform plugin bridges that gap, exposing Swift/Objective-C and Kotlin/Java capabilities to your Dart code through a typed channel.
- Package: pure Dart, no native code.
- Plugin: Dart API plus platform-specific native implementations.
You write a plugin whenever you need hardware (sensors, BLE), OS services (notifications, keychain), or a native SDK that has no Dart equivalent. In this lesson we author a federated plugin that surfaces native Kotlin and Swift APIs to Dart.
Federated Plugin Architecture
A federated plugin splits responsibilities across several packages so different parties can own different platforms:
- app-facing package (
battery): the public Dart API developers import. - platform interface (
battery_platform_interface): an abstract contract all implementations must satisfy. - platform packages (
battery_android,battery_ios): concrete native implementations registered viapubspec.yaml.
This decoupling lets a third party add, say, a Windows implementation without touching the app-facing package. The interface package is the linchpin contract.
The Platform Interface Contract
The platform interface uses the plugin_platform_interface package. It declares an abstract base class with a MethodChannel-free contract, plus a default instance other packages override.
The PlatformInterface token-verification prevents implementers from extends-ing and breaking the contract; they must use implements guarded by verifyToken.
import 'package:plugin_platform_interface/plugin_platform_interface.dart';
abstract class BatteryPlatform extends PlatformInterface {
BatteryPlatform() : super(token: _token);
static final Object _token = Object();
static BatteryPlatform _instance = MethodChannelBattery();
static BatteryPlatform get instance => _instance;
static set instance(BatteryPlatform value) {
PlatformInterface.verifyToken(value, _token);
_instance = value;
}
Future<int> getBatteryLevel() {
throw UnimplementedError('getBatteryLevel() is not implemented.');
}
}MethodChannel: The Default Implementation
The default implementation talks to native code over a MethodChannel. Each channel has a unique name shared by Dart and native sides. invokeMethod serializes arguments using the standard message codec and awaits a native reply.
Keep channel names namespaced (reverse-DNS) to avoid collisions across plugins.
import 'package:flutter/services.dart';
import 'battery_platform_interface.dart';
class MethodChannelBattery extends BatteryPlatform {
final MethodChannel _channel =
const MethodChannel('com.example.battery/methods');
@override
Future<int> getBatteryLevel() async {
final level = await _channel.invokeMethod<int>('getBatteryLevel');
if (level == null) {
throw PlatformException(code: 'NO_LEVEL', message: 'Level unavailable');
}
return level;
}
}Android: Kotlin Plugin Registration
On Android the native side implements FlutterPlugin and MethodChannel.MethodCallHandler. In onAttachedToEngine you wire a MethodChannel with the same name used in Dart, then route incoming calls in onMethodCall.
result.success(value)resolves the Dart Future.result.error(code, msg, details)throws aPlatformExceptionin Dart.result.notImplemented()signals an unknown method.
This is Kotlin, not Dart, so it is illustrative only.
iOS: Swift Plugin Registration
On iOS you conform to FlutterPlugin and register in register(with:), creating a FlutterMethodChannel with the matching name. handle(_:result:) dispatches calls and replies via the FlutterResult callback.
For federated plugins the platform package declares its native entry point under flutter.plugin.platforms.ios in pubspec.yaml, pointing at the Swift class. The Dart registrant is wired automatically.
Declaring the Federated pubspec
The platform implementation packages announce themselves via flutter.plugin.platforms. The dartPluginClass is registered with the platform interface at startup, and pluginClass names the native class.
Crucially the app-facing package lists each platform package under default_package, so adding a platform is a pubspec change, not a code change.
Endorsing Platform Implementations
The app-facing package endorses implementations by depending on them in its pubspec.yaml. Endorsed packages are pulled in transitively, so app developers add one dependency and get every platform.
At runtime, each platform package's registerWith() sets the interface's instance to its own implementation. The Dart API then calls through BatteryPlatform.instance without knowing which platform answered.
// battery_android registers itself at startup
import 'battery_platform_interface.dart';
class BatteryAndroid extends BatteryPlatform {
/// Registered via dartPluginClass in pubspec.yaml.
static void registerWith() {
BatteryPlatform.instance = BatteryAndroid();
}
@override
Future<int> getBatteryLevel() {
// Delegates to the MethodChannel under the hood.
return MethodChannelBattery().getBatteryLevel();
}
}The App-Facing Dart API
The public package wraps the interface in an ergonomic, well-documented API. App developers never touch channels or platform classes — they call clean Dart methods.
Keep this layer thin: validation, convenience overloads, and documentation. All real work lives behind BatteryPlatform.instance.
import 'battery_platform_interface.dart';
class Battery {
/// Returns the current battery level as a percentage (0-100).
Future<int> get batteryLevel => BatteryPlatform.instance.getBatteryLevel();
/// Convenience: true when the device is critically low.
Future<bool> get isCritical async => (await batteryLevel) <= 15;
}Streaming Native Events with EventChannel
For continuous data (charging state, sensor streams) a single method call is not enough. Use an EventChannel: the native side pushes events through a StreamHandler/FlutterEventSink, and Dart exposes them as a Stream.
receiveBroadcastStream lazily starts the native listener on first subscription and tears it down on cancel.
import 'package:flutter/services.dart';
class BatteryStream {
final EventChannel _events =
const EventChannel('com.example.battery/charging');
Stream<bool> get onChargingChanged => _events
.receiveBroadcastStream()
.map((event) => event == 'charging');
}Type-Safe Channels with Pigeon
Hand-written channels are stringly-typed and error-prone. Pigeon generates type-safe Dart, Kotlin, and Swift bindings from a single Dart definition file, eliminating method-name typos and codec mismatches.
You annotate an abstract class with @HostApi() (Dart calls native) or @FlutterApi() (native calls Dart), run the Pigeon generator, and wire the generated classes — no manual invokeMethod strings.
import 'package:pigeon/pigeon.dart';
class BatteryInfo {
int? level;
bool? isCharging;
}
@HostApi()
abstract class BatteryHostApi {
BatteryInfo getBatteryInfo();
}
@FlutterApi()
abstract class BatteryFlutterApi {
void onLevelChanged(int level);
}Quick Check
You are publishing a Flutter plugin and want third parties to add new platform implementations (e.g. Windows) without modifying or forking your app-facing package. Which architecture and mechanism makes that possible?
Recap
You learned to author a federated platform plugin exposing native Kotlin and Swift APIs to Dart:
- Architecture: app-facing package, platform interface, and per-platform implementations.
- Contract: an abstract
PlatformInterfacewith token verification and a swappableinstance. - Channels:
MethodChannelfor request/response,EventChannelfor native event streams, with matching names on both sides. - Native sides: Kotlin
onMethodCalland Swifthandle(_:result:)resolving via success/error. - Endorsement: pubspec wires
dartPluginClassandpluginClassso platforms register themselves. - Pigeon: generates type-safe bindings to replace fragile string-based channels.
With this you can wrap any native SDK behind a clean, testable Dart API.
Sıkça Sorulan Sorular
“iOS ve Android için Özel Platform Eklentileri Yazma” dersi ücretsiz mi?
Evet — “iOS ve Android için Özel Platform Eklentileri Yazma” dersin tüm metni burada web'de ücretsiz olarak okunabilir. Etkileşimli olarak pratik yapmak (yerleşik kod editörü ve 7/24 yapay zeka koçu) ve Flutter Mobile Development kursunun geri kalanını açmak için CoddyKit PRO'ya yükselt. Flutter Mobile Development kursu toplamda 4 dersten oluşur.
“iOS ve Android için Özel Platform Eklentileri Yazma” dersinde ne öğreneceğim?
Yerel Kotlin ve Swift API'lerini Dart'a açan federatif eklentiler yazın. Flutter Mobile Development ile uygulamalı kodu tarayıcıda doğrudan çalıştırarak pratik yaparsın ve 7/24 yapay zeka koçu dersi çalışırken sorularını yanıtlar.
Flutter Mobile Development öğrenmeye başlamak için deneyim gerekli mi?
Önceden deneyim gerekmez. CoddyKit'te Flutter Mobile Development, başlangıçtan ileri seviyeye kadar yapılandırıldığı için buradan başlayabilir veya başından başlayıp kendi hızında ilerleme yapabilirsin. Bu, 4 dersinin 3. dersidir.
“iOS ve Android için Özel Platform Eklentileri Yazma” dersi ne kadar sürer?
Çoğu CoddyKit dersi yaklaşık 5–10 dakika sürer. Her biri kısa ve etkileşimli olduğu için sabit ilerleme yaparsın ve web ile uygulama arasında tam olarak bıraktığın yerden devam edebilirsin.
Bu Flutter Mobile Development dersinde kod yazıp çalıştırabilir miyim?
Evet. Her Flutter Mobile Development dersi yerleşik bir kod editörü içerir, bu sayede tarayıcıda gerçek kod yazıp çalıştırabilir ve anlık yapay zeka geri bildirimi alırsın — yerel kurulum gerekli değildir.
Bu kursun tüm dersleri
- dart:ffi ile C Kütüphanelerini Çağırma
- Pigeon ile Tür Güvenli Platform Kanalları
- iOS ve Android için Özel Platform Eklentileri Yazma
- Arka Plan İzolatları ve Yerel Bellek Yönetimi