Flutter扩展功能插件dart_extensionz的使用

当然，以下是一个关于如何在Flutter项目中使用dart_extensionz插件的示例。dart_extensionz是一个允许你从Dart代码中调用本地（原生）代码的插件。尽管这个插件的具体名称和可用性可能有所变化，但以下示例展示了如何在Flutter中集成和使用Dart扩展插件的一般步骤。

1. 添加依赖

首先，在你的pubspec.yaml文件中添加dart_extensionz（或类似功能的插件）的依赖。注意，由于dart_extensionz可能不是一个真实存在的插件，这里我们将使用假设的插件名flutter_native_extensions作为示例。

dependencies:
  flutter:
    sdk: flutter
  flutter_native_extensions: ^0.1.0  # 假设的版本号

2. 获取平台特定的代码

你需要为Android和iOS平台编写原生代码，并通过Dart扩展来调用这些代码。

Android

在android/app/src/main/kotlin/.../MainActivity.kt（或Java目录，如果你使用Java）中，你可以定义一个原生方法：

package com.example.yourapp

import io.flutter.embedding.android.FlutterActivity
import io.flutter.embedding.engine.FlutterEngine
import io.flutter.plugin.common.MethodCall
import io.flutter.plugin.common.MethodChannel
import io.flutter.plugins.GeneratedPluginRegistrant

class MainActivity: FlutterActivity() {
    private val CHANNEL = "com.example.yourapp/channel"

    override fun configureFlutterEngine(flutterEngine: FlutterEngine) {
        super.configureFlutterEngine(flutterEngine)
        GeneratedPluginRegistrant.registerWith(flutterEngine)

        MethodChannel(flutterEngine.dartExecutor.binaryMessenger, CHANNEL).setMethodCallHandler {
            call, result ->
            if (call.method == "getBatteryLevel") {
                // 这里调用Android API获取电池电量
                val batteryManager = getSystemService(Context.BATTERY_SERVICE) as BatteryManager
                val batteryLevel = batteryManager.intProperty(BatteryManager.BATTERY_PROPERTY_CAPACITY)

                // 将结果发送回Dart
                result.success(batteryLevel)
            } else {
                result.notImplemented()
            }
        }
    }
}

iOS

在ios/Runner/AppDelegate.swift中，添加Swift代码来处理Dart调用：

import UIKit
import Flutter

@UIApplicationMain
@objc class AppDelegate: FlutterAppDelegate {
  override func application(
    _ application: UIApplication,
    didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?
  ) -> Bool {
    GeneratedPluginRegistrant.register(with: self)

    let controller : FlutterViewController = window?.rootViewController as! FlutterViewController
    let channel = FlutterMethodChannel(name: "com.example.yourapp/channel", binaryMessenger: controller.binaryMessenger)
    channel.setMethodCallHandler({
      (call: FlutterMethodCall, result: @escaping FlutterResult) in
      if call.method == "getBatteryLevel" {
        UIDevice.current.isBatteryMonitoringEnabled = true
        let batteryLevel = UIDevice.current.batteryLevel
        result(batteryLevel)
      } else {
        result(FlutterMethodNotImplemented)
      }
    })
    return super.application(application, didFinishLaunchingWithOptions: launchOptions)
  }
}

3. Dart代码调用原生方法

在你的Dart代码中，你可以通过MethodChannel来调用上面定义的原生方法：

import 'package:flutter/services.dart';

class BatteryLevel {
  static const MethodChannel _channel = MethodChannel('com.example.yourapp/channel');

  static Future<double> getBatteryLevel() async {
    final double batteryLevel = await _channel.invokeMethod('getBatteryLevel');
    return batteryLevel;
  }
}

void main() {
  runApp(MyApp());
}

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: Scaffold(
        appBar: AppBar(
          title: const Text('Battery Level'),
        ),
        body: Center(
          child: FutureBuilder<double>(
            future: BatteryLevel.getBatteryLevel(),
            builder: (context, snapshot) {
              if (snapshot.hasData) {
                return Text('Battery Level: ${snapshot.data}%');
              } else if (snapshot.hasError) {
                return Text('${snapshot.error}');
              }
              return CircularProgressIndicator();
            },
          ),
        ),
      ),
    );
  }
}

这个示例展示了如何在Flutter项目中集成和使用Dart扩展插件来调用原生平台特定的功能。请根据你实际使用的插件和API调整代码。