混合开发

static const platform = const MethodChannel('samples.flutter.dev/battery');
    try {
      final int result = await platform.invokeMethod('getBatteryLevel');
      batteryLevel = 'Battery level at $result % .';
    } on PlatformException catch (e) {
      batteryLevel = "Failed to get battery level: '${e.message}'.";
    }

class MainActivity() : FlutterActivity() {
  private val CHANNEL = "samples.flutter.dev/battery"

  override fun onCreate(savedInstanceState: Bundle?) {
    super.onCreate(savedInstanceState)

    GeneratedPluginRegistrant.registerWith(this)
    MethodChannel(flutterView, CHANNEL).setMethodCallHandler { call, result ->
      // Note: this method is invoked on the main thread.
      if (call.method == "getBatteryLevel") {
        val batteryLevel = getBatteryLevel()//android平台api调用获取
        if (batteryLevel != -1) {
          result.success(batteryLevel)
        } else {
          result.error("UNAVAILABLE", "Battery level not available.", null)
        }
      } else {
        result.notImplemented()
      }
    }

//从安卓原生页面跳转到FlutterDemoActivity页面使用如下方法将routeName传递过去：
Intent intent = new Intent(this, FlutterDemoActivity.class);
Bundle bundle = new Bundle();
bundle.putString("routeName", "first");
intent.putExtras(bundle);
startActivity(intent);

//flutter_host_android工程的java源码包下新建一个FlutterDemoActivity类，onCreate方法中的实现如下：
public static final String CHANNEL_NAME = "com.flutterbus/demo";
    @Override
    protected void onCreate(@Nullable Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        // 获取由上一个页面传过来的routeName
        String routeName = "";
        Intent intent = getIntent();
        if (intent != null && intent.getExtras() != null) {
            routeName = intent.getExtras().getString("routeName");
        }

         // 根据指定routeName创建FlutterView用来展示对应dart中的Widget
        FlutterView flutterView = Flutter.createView(this, this.getLifecycle(), routeName);

        // 创建Platform Channel用来和Flutter层进行交互
        new MethodChannel(flutterView, CHANNEL_NAME).setMethodCallHandler(new MethodChannel.MethodCallHandler() {
            @Override
            public void onMethodCall(MethodCall methodCall, MethodChannel.Result result) {
                methodCall(methodCall, result);
            }
        });
        setContentView(flutterView);
    }

    /**
     * 处理dart层传来的方法调用
     */
    private void methodCall(MethodCall call, MethodChannel.Result result) {
        if (call.method.equals("gotoNativePage")) {
            startActivity(new Intent(this, NativeActivity.class));
            result.success(true);
        } else {
            result.notImplemented();
        }
    }
    
    //routeName在Flutter端是如何起到作用的呢，可以看下Flutter module中dart代码:
void main() => runApp(_widgetForRoute(window.defaultRouteName));

Widget _widgetForRoute(String route) {
  switch (route) {
    case 'first':
      return MyApp();
    case 'second':
      return MyApp();
    default:
      return Center(
        child: Text('Unknown route: $route', textDirection: TextDirection.ltr),
      );
  }
}

static final String channelName = "com.flutterbus/demo";

Future<Null> jumpToNativePage() async {
    MethodChannel methodChannel = MethodChannel(channelName);
    await methodChannel.invokeMethod("gotoNativePage");
}

// With a new FlutterEngine.
val flutterFragment = FlutterFragment.withNewEngine()
    .initialRoute("myInitialRoute/")
    .build()

FlutterFragment flutterFragment = FlutterFragment.withNewEngine()
    .dartEntrypoint("mySpecialEntrypoint")
    .build();

@override
void initState() {
    super.initState();

    FlutterBoost.singleton.registerPageBuilders({
      'flutterbus://flutterFirstPage': (pageName, params, _) {
        print("first flutterPage params:$params");
        ...
        return FirstPage();
      },
      'flutterbus://flutterSecondPage': (pageName, params, _) {
        print("second flutterPage params:$params");
        ...
        return SecondPage();
      },
    });

    FlutterBoost.handleOnStartPage();
}

@override
Widget build(BuildContext context) {
    return MaterialApp(
        title: 'Flutter Boost example',
        builder: FlutterBoost.init(),
        home: Container());
}

    public static void init(final Application app) {
        //此处必须启动初始化，主要是载入Flutter引擎文件
        FlutterMain.startInitialization(app);

        FlutterBoostPlugin.init(new IPlatform() {
            @Override
            public Application getApplication() {
                return app;
            }

            @Override
            public Activity getMainActivity() {
                return MainActivity.sRef.get();
            }

            @Override
            public boolean isDebug() {
                return true;
            }

            @Override
            public boolean startActivity(Context context, String url, int requestCode) {
                Debuger.log("startActivity url="+url);

                return PageRouter.openPageByUrl(context,url,requestCode);
            }

            @Override
            public Map getSettings() {
                return null;
            }
        });
    }

FlutterBoost.singleton.openPage("flutterbus://nativeFirstPage", {
                "query": {"description": "大家好，我来自First Flutter页面!!!!!!!!"}
              });

FlutterBoost.singleton.openPage("flutterbus://flutterSecondPage", {});

Navigator.of(context).push(MaterialPageRoute(builder: (context){
                return SecondPage(enterType: 1,);
              }));

void exitPage(BuildContext context) {
    if (enterType == 0) {
      FlutterBoost.singleton.closePageForContext(context);
    } else {
      Navigator.pop(context);
    }
}