Flutter项目中与android原生交互

1、右击项目名称，new->module新建FlutterPlugin，添加android和flutter交互的桥梁 image.png

2、在pubspec.yaml中添加
hello_plugin:
path:填写路径

---

准备工作到这里结束，下面看下代码。

插件端
android端会生成HelloPlugin.java文件，示例代码：

/** HelloPlugin */
public class HelloPlugin implements MethodCallHandler {
  /** Plugin registration. */
  public static void registerWith(Registrar registrar) {
    final MethodChannel channel = new MethodChannel(registrar.messenger(), "hello_plugin");
    channel.setMethodCallHandler(new HelloPlugin());
  }

  @Override
  public void onMethodCall(MethodCall call, Result result) {
    if (call.method.equals("getPlatformVersion")) {
      result.success("Android " + android.os.Build.VERSION.RELEASE);
    } else {
      result.notImplemented();
    }
  }
}

这里我们可以注释掉registerWith方法里的代码，放到MainActivity中注册

new MethodChannel(getFlutterView(), "hello_plugin")
            .setMethodCallHandler((methodCall, result) -> {
              switch (methodCall.method){
                case "getPlatformVersion": {
                    result.success("Android " + android.os.Build.VERSION.RELEASE);
                    break;
                }
                default:result.notImplemented();
              }
            });

flutter端生成的hello_plugin.dart文件中 同样也会完成注册：

class FlutterPlugin {
  static const MethodChannel _channel =
      const MethodChannel('hello_plugin');

  static Future<String> get platformVersion async {
    final String version = await _channel.invokeMethod('getPlatformVersion');
    return version;
  }
 
}

接下来就是传值了（flutter->android）
hello_plugin中实现方法

static Future<void> dosetAAA(String data) async {
       await _channel.invokeMethod("dosetAAA", {"data":data});
  }

main.dart中调用该方法

await HelloPlugin.dosetAAA("hahahaha~");

MainActivity中的onMethodCall方法中判断call返回参数，处理相应逻辑

case "dosetAAA":
 String data = call.argument("data");  //拿到参数data

android->flutter参考示例platformVersion
方法回调：
hello_plugin.dart中注册EventChannel

static const EventChannel _eventChannel = EventChannel("startVideoEvent");

添加监听

static eventVideoStart(EventHandler onEvent, EventHandler onError) {
    _eventChannel.receiveBroadcastStream().listen(onEvent, onError: onError);

  }

main.dart中调用

HelloPlugin.eventVideoStart(videoStart,errorEvent);

MainActivity中实现StreamHandler，然后发射事件

new EventChannel(getFlutterView(), "startVideoEvent")
            .setStreamHandler(new EventChannel.StreamHandler() {
              @Override
              public void onListen(Object o, EventChannel.EventSink eventSink) {
                eventSink.success("true");
              }

              @Override
              public void onCancel(Object o) {

              }
            });

最后记录一下android小白一点点的学习结果：
activity和service通过Intent去传递数据，

Intent startIntent = new Intent(this,MainActivity.class);
        startIntent.putExtras(intent);
        startActivity(startIntent);

Intent intent = new Intent(MainActivity.this,RecMsgService.class);
intent.putExtra("method", "videoSuccess");
startService(intent);

Service启动后会调用onStartCommand方法