flutter-plugins（Flutter plugins 命令行）

flutter-plugin-generator

Goal

Scaffolds and configures Flutter plugin packages, handling standard method channels, FFI integrations, and federated plugin architectures. It configures platform-specific native code environments, implements Android v2 embedding lifecycle interfaces, and establishes platform interface packages.

Decision Logic

Use the following decision tree to determine the plugin architecture and template:

1. Does the plugin require C/C++ native code via dart:ffi?

- Yes: Use --template=plugin_ffi. - *Note:* FFI plugins support bundling native code and method channel registration, but *not* method channels themselves. - No: Proceed to step 2.

1. Does the plugin require BOTH dart:ffi and Method Channels?

- Yes: Use --template=plugin (Non-FFI). You must configure FFI manually within the standard plugin structure. - No: Proceed to step 3.

1. Will the plugin be developed by multiple teams or require highly decoupled platform implementations?

- Yes: Implement a Package-Separated Federated Plugin (App-facing package, Platform Interface package, Platform Implementation packages). - No: Implement a standard monolithic plugin.

Instructions

1. Gather Plugin Requirements STOP AND ASK THE USER:

- What is the plugin name? - What is the organization name (reverse domain notation, e.g., com.example)? - Which platforms should be supported (comma-separated: android,ios,web,linux,macos,windows)? - Do you need an FFI plugin or a standard Method Channel plugin? - Do you prefer Java or Kotlin for Android? Objective-C or Swift for iOS? - Should this be a federated plugin?

1. Generate the Plugin Package Execute the Flutter CLI command based on the user's parameters. *Standard Plugin Example:* flutter create --org com.example --template=plugin --platforms=android,ios,macos -a kotlin -i swift my_plugin *FFI Plugin Example:* flutter create --template=plugin_ffi my_ffi_plugin
2. Configure Federated Plugin Architecture (If Applicable) If the user requested a federated plugin, configure the pubspec.yaml of the app-facing package to endorse the platform implementations. # App-facing pubspec.yaml flutter: plugin: platforms: android: default_package: my_plugin_android windows: default_package: my_plugin_windows dependencies: my_plugin_android: ^1.0.0 my_plugin_windows: ^1.0.0 For the platform implementation packages, define the implements key: # Platform implementation pubspec.yaml (e.g., my_plugin_windows) flutter: plugin: implements: my_plugin platforms: windows: pluginClass: MyPlugin
3. Prepare Native Environments for Editing Before modifying native code, you MUST build the example app to resolve dependencies and generate necessary files. cd my_plugin/example flutter build apk --config-only # For Android flutter build ios --no-codesign --config-only # For iOS flutter build windows # For Windows
4. Implement Android v2 Embedding Lifecycle Modify the Android plugin class (e.g., android/src/main/kotlin/com/example/my_plugin/MyPlugin.kt). Extract logic from registerWith() into a private method shared with onAttachedToEngine(). Implement ActivityAware or ServiceAware if context is needed. package com.example.my_plugin import androidx.annotation.NonNull import io.flutter.embedding.engine.plugins.FlutterPlugin import io.flutter.embedding.engine.plugins.activity.ActivityAware import io.flutter.embedding.engine.plugins.activity.ActivityPluginBinding import io.flutter.plugin.common.MethodCall import io.flutter.plugin.common.MethodChannel import io.flutter.plugin.common.MethodChannel.MethodCallHandler import io.flutter.plugin.common.MethodChannel.Result class MyPlugin: FlutterPlugin, MethodCallHandler, ActivityAware {private lateinit var channel: MethodChannel override fun onAttachedToEngine(@NonNull flutterPluginBinding: FlutterPlugin.FlutterPluginBinding) {setupChannel(flutterPluginBinding.binaryMessenger)} // Shared private method for v1 and v2 embedding compatibility private fun setupChannel(messenger: BinaryMessenger) {channel = MethodChannel(messenger, "my_plugin") channel.setMethodCallHandler(this)} override fun onMethodCall(@NonNull call: MethodCall, @NonNull result: Result) {if (call.method == "getPlatformVersion") {result.success("Android ${android.os.Build.VERSION.RELEASE}")} else {result.notImplemented()}} override fun onDetachedFromEngine(@NonNull binding: FlutterPlugin.FlutterPluginBinding) {channel.setMethodCallHandler(null)} override fun onAttachedToActivity(binding: ActivityPluginBinding) {// Handle Activity attachment} override fun onDetachedFromActivityForConfigChanges() {} override fun onReattachedToActivityForConfigChanges(binding: ActivityPluginBinding) {} override fun onDetachedFromActivity() {}}
5. Validate and Fix Run the plugin tests and analyzer to ensure the generated code is valid. cd my_plugin flutter analyze flutter test *If the analyzer reports missing dependencies or unresolved native symbols, verify that step 4 (building the example app) was executed successfully. Fix any missing imports in the native code blocks.*

Constraints

• Never attempt to use Method Channels inside a package created with --template=plugin_ffi. If both are required, use --template=plugin.
• Always build the example project (flutter build <platform>) at least once before attempting to edit or analyze native Android (build.gradle), iOS (.xcworkspace), or Windows (.sln) files.
• Never leave public members undocumented in the Dart API (lib/<package_name>.dart).
• Always use the v2 Android embedding (FlutterPlugin). Do not rely solely on the deprecated PluginRegistry.Registrar.
• Never edit the .android or .ios directories inside a Flutter module; only edit the native code inside the plugin's android/ or ios/ directories.