Flutter混合开发-通信
参考：https://www.jianshu.com/p/1a131deeee75
参考：https://www.jianshu.com/p/1770ded8f50f
一.混编
1.咸鱼模式
Flutter打包成aar嵌入到原生工程
2.Google模式，Flutter页面嵌入原生
public class MyFlutterActivity extends FragmentActivity {
FlutterFragment flutterFragment;
@Override
protected void onCreate(@Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_my_flutter);
initFlutterEngine();
attachFlutterFragment();
}
String ENGINE_ID = "a";
private FlutterEngine initFlutterEngine() {
FlutterEngine flutterEngine = FlutterEngineCache.getInstance().get(ENGINE_ID);
if (null == flutterEngine) {
flutterEngine = new FlutterEngine(this);
flutterEngine.getNavigationChannel().setInitialRoute("/");
flutterEngine.getDartExecutor().executeDartEntrypoint(DartExecutor.DartEntrypoint.createDefault());
FlutterEngineCache
.getInstance()
.put(ENGINE_ID, flutterEngine);
messageChannelFunction(this,flutterEngine);
}
return flutterEngine;
}
private void attachFlutterFragment() {
if (null == flutterFragment) {
flutterFragment =
FlutterFragment.withCachedEngine(ENGINE_ID)
.shouldAttachEngineToActivity(true)
.build();
}
getSupportFragmentManager()
.beginTransaction()
.add(R.id.container, flutterFragment)
.commit();
}
}
二.通信
1.BasicMessageChannel 方式
跨Native，Flutter发送消息可接收消息
1.1Flutter端给原生发消息
//Flutter 端
//创建 BasicMessageChannel
// flutter_and_native_100 为通信标识
// StandardMessageCodec() 为参数传递的 编码方式
static const messageChannel = const BasicMessageChannel(
'flutter_and_native_100', StandardMessageCodec());
//发送消息
Future<Map> sendMessage(Map arguments) async {
Map reply = await messageChannel.send(arguments);
//解析 原生发给 Flutter 的参数
int code = reply["code"];
String message = reply["message"];
//更新 Flutter 中页面显示
setState(() {
_counter = "code:$code message:$message";
});
return reply;
}
//原生端
private BasicMessageChannel<Object> mMessageChannel;
private void messageChannelFunction(Context mContext, FlutterEngine flutterEngine) {
//消息接收监听
//BasicMessageChannel （主要是传递字符串和一些半结构体的数据）
//创建通
mMessageChannel = new BasicMessageChannel<Object>(flutterEngine.getDartExecutor(), "flutter_and_native_100", StandardMessageCodec.INSTANCE);
// 接收消息监听
mMessageChannel.setMessageHandler(new BasicMessageChannel.MessageHandler<Object>() {
@Override
public void onMessage(Object o, BasicMessageChannel.Reply<Object> reply) {
Map<Object, Object> arguments = (Map<Object, Object>) o;
//方法名标识
String lMethod = (String) arguments.get("method");
//测试 reply.reply()方法 发消息给Flutter
if (lMethod.equals("test")) {
Toast.makeText(mContext, "flutter 调用到了 android test", Toast.LENGTH_SHORT).show();
//回调Flutter
Map<String, Object> resultMap = new HashMap<>();
resultMap.put("message", "reply.reply 返回给flutter的数据");
resultMap.put("code", 200);
//回调 此方法只能使用一次
reply.reply(resultMap);
} else if (lMethod.equals("test2")) {
//测试 mMessageChannel.send 发消息给Flutter
//Android 可通过这个方法来主动向 Flutter中发送消息
//只有Flutter 中注册了消息监听 才能接收到这个方法向 Flutter 中发送的消息
// channelSendMessage();
} else if (lMethod.equals("test3")) {
//测试通过Flutter打开Android Activity
Toast.makeText(mContext, "flutter 调用到了 android test3", Toast.LENGTH_SHORT).show();
Intent lIntent = new Intent(MyFlutterActivity.this, TestBasicMessageActivity.class);
mContext.startActivity(lIntent);
}
}
});
}
1.2 原生给Flutter发消息
//原生端
private void channelSendMessage() {
mMessageChannel = new BasicMessageChannel<Object>(initFlutterEngine().getDartExecutor(), "flutter_and_native_100", StandardMessageCodec.INSTANCE);
Toast.makeText(this, "flutter 调用到了 android test", Toast.LENGTH_SHORT).show();
//构建参数
Map<String, Object> resultMap = new HashMap<>();
resultMap.put("message", "reply.reply 返回给flutter的数据");
resultMap.put("code", 200);
//向 Flutter 中发送消息
//参数 二可以再次接收到 Flutter 中的回调
//也可以直接使用 mMessageChannel.send(resultMap）
mMessageChannel.send(resultMap, new BasicMessageChannel.Reply<Object>() {
@Override
public void reply(Object o) {
Log.d("mMessageChannel", "mMessageChannel send 回调 " + o); //消息没有收到？？？
}
});
}
//Fluttrer 端
void messageChannelFunction(){
messageChannel.setMessageHandler((message) async {
print('message: $message');
return '返回Native端的数据001';//这是native端的响应 ，执行了
});
}
2.MethodChannel 方式
直接跨Native，Flutter调用方法
2.1 Native端 发送 + 监听接收
/**
* 设置MethodChannel 监听
*
* @param flutterEngine
*/
private void setMethodChannel(FlutterEngine flutterEngine) {
MethodChannel channel = new MethodChannel(flutterEngine.getDartExecutor(), "study_3/methodChannel");
channel.setMethodCallHandler(new MethodChannel.MethodCallHandler() {
@Override
public void onMethodCall(MethodCall methodCall, MethodChannel.Result result) {
switch (methodCall.method) {
// case NATIVE_METHOD_LOGIN:
// login(context, (String) methodCall.argument("phone"), (String) methodCall.argument("code"));
// break;
}
}
});
}
private void invokeMethodChannel(FlutterEngine flutterEngine) {
MethodChannel channel = new MethodChannel(flutterEngine.getDartExecutor(), "cn.withflutter.plugins.flutter");
//在Android端调用Flutter中的getInputParams方法，参数是以Json的格式传递。这里是无参方法使用null
channel.invokeMethod("getInputParams", "{'arg1':'来自Native'}", new MethodChannel.Result() {
@Override
public void success(@Nullable Object result) {
}
@Override
public void error(String errorCode, @Nullable String errorMessage, @Nullable Object errorDetails) {
}
@Override
public void notImplemented() {
}
});
}
2.2 Flutter端 发送+监听接收
class PluginChannel {
static const _methodChannelName = "study_3/methodChannel";
static const _methodChannel = MethodChannel(_methodChannelName);
static void invokeMethod() {
_methodChannel.invokeMethod("getAge", {"name": "lili"}).then((result) {
print('flutter receive response:$result');
});
}
static void listenMethod() {
_methodChannel.setMethodCallHandler((methodCall) async {
print('flutter listen:$methodCall');
return "男";
});
}
}
3.EventChannel 模式
EventChannel并没有分别提供发送和收听消息的方法，它只提供了一个receiveBroadcastStream方法，用于发送消息，同时返回一个流（Stream），用于监听平台插件成功返回的所有事件信息，这个流可以被监听不止一次。因此我们可以用于native端需要持续传递数据到flutter的情况，比如监听电量，调用摄像头等等
flutter:
class PluginChannel {
static const _eventChannelName = "study_3/eventChannel";
static const _eventChannel = EventChannel(_eventChannelName);
static void event() {
_eventChannel.receiveBroadcastStream("event arg")
.listen((result) {
print('flutter listen:$result');
});
}
}
android：
private void eventChannelDemo(FlutterEngine flutterEngine){
EventChannel channel = new EventChannel(flutterEngine.getDartExecutor(),"study_3/methodChannel");
channel.setStreamHandler(new EventChannel.StreamHandler() {
@Override
public void onListen(Object arguments, EventChannel.EventSink events) {
events.success(1);
events.success(2);
events.success(3);
events.success(4);
events.endOfStream();
}
@Override
public void onCancel(Object arguments) {
}
});
}
