准备
1、nav端（ios、android）调试原生实现。
2、flutter_app(一个), 调试插件。
3、flutter_plugin(一个), 写插件。
三种Channel
BasicMessageChannel：用于传递字符串和半结构化的信息
MethodChannel：用于传递方法调用（method invocation）
EventChannel：用于数据流（event streams）的通信
BinaryMessage.png
Flutter端对三种Channel的书写
1、定义
//字符串需和原生保持一致
MethodChannel _methodChannel = MethodChannel("flutter/live/methodChannel");
EventChannel _eventChannel = EventChannel("flutter/live/eventChannel");
BasicMessageChannel _messageChannel = BasicMessageChannel("flutter/live/messageChannel", StandardMessageCodec());
2、原生调用Flutter
_methodChannel.setMethodCallHandler((call) async {
print('_methodChannel 收到：' + call.toString());
});
_eventChannel.receiveBroadcastStream().listen((event) {
print('_eventChannel 收到：' + event);
});
_messageChannel.setMessageHandler((message) async {
print('_messageChannel 收到：' + message);
});
3、Flutter调用原生
_methodChannel.invokeMethod("startLive",{"url" : "rtmp://192.168.101.164"});
Map msg = {"startLive":"rtmp://192.168.101.164"};
_messageChannel.send(msg);
原生端实现书写
两种方案
1、创建flutter plugin项目。
- 1.1 上传https://pub.flutter-io.cn/ 或github，在Flutter项目中引用
dio: ^3.0.6
- 1.2 本地引用
flutter_ijkplayer:
path:
plugins/flutter_ijkplayer
2、直接在Flutter项目文件夹下的iOS文件夹和Android文件夹中写实现逻辑，所以这种方案只能在本项目使用。
iOS端对三种Channel的书写
1、创建
- (void)createMethodChannel:(NSObject<FlutterPluginRegistrar>*)registrar {
FlutterMethodChannel* methodChannel = [FlutterMethodChannel
methodChannelWithName:@"flutter/live/methodChannel"
binaryMessenger:[registrar messenger]];
[registrar addMethodCallDelegate:self channel:methodChannel];
}
- (void)createEventChannel:(NSObject<FlutterPluginRegistrar>*)registrar {
FlutterEventChannel *eventChannel = [FlutterEventChannel eventChannelWithName:@"flutter/live/eventChannel" binaryMessenger:[registrar messenger]];
[eventChannel setStreamHandler:self];
}
- (void)createMessageChannel:(NSObject<FlutterPluginRegistrar>*)registrar {
FlutterBasicMessageChannel *messageChannel = [FlutterBasicMessageChannel messageChannelWithName:@"flutter/live/messageChannel" binaryMessenger:[registrar messenger]];
[messageChannel setMessageHandler:^(id _Nullable message, FlutterReply _Nonnull callback) {
NSLog(@"MessageChannel 收到：%@",message);
// NSString *method=message[@"method"];
// if ([method isEqualToString:@"startLive"]) {
// NSLog(@"Flutter MessageChannel 收到:startLive");
// }
}];
}
2、监听回调
1、MethodChannel
- (void)handleMethodCall:(FlutterMethodCall*)call result:(FlutterResult)result {
if ([call.method isEqualToString:@"startLive"]) {
NSLog(@"Flutter MethodChannel 收到:startLive");
}
else {
result(FlutterMethodNotImplemented);
}
}
2、EventChannel，通过绑定FlutterEventSink，让eventSink来发送消息
@property (nonatomic) FlutterEventSink eventSink;
- (FlutterError * _Nullable)onCancelWithArguments:(id _Nullable)arguments {
_eventSink = nil;
return nil;
}
- (FlutterError * _Nullable)onListenWithArguments:(id _Nullable)arguments eventSink:(nonnull FlutterEventSink)events {
_eventSink = events;
return nil;
}
3、BasicMessageChannel 创建的时候绑定
注意事项：
如果直接在Flutter项目中直接写plugin，每次运行都会更新GeneratedPluginRegistrant这个类，是按podfile的描述重新生成，所以不要在GeneratedPluginRegistrant里边写。
1、可以直接在AppDelegate里写
2、可以封装FlutterChannelPlugin工具类，在AppDelegate入口函数调用
- (BOOL)application:(UIApplication *)application
didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
[GeneratedPluginRegistrant registerWithRegistry:self];
[FlutterChannelPlugin registerWithRegistrar:[self registrarForPlugin:@"FlutterChannelPlugin"]];
}
2.1、FlutterChannelPlugin需遵循代理（FlutterPlugin,FlutterStreamHandler）
2.2、FlutterChannelPlugin需实现FlutterPlugin代理的类方法，作为入口
+ (void)registerWithRegistrar:(NSObject<FlutterPluginRegistrar>*)registrar {
FlutterChannelPlugin *plugin = [[FlutterChannelPlugin alloc] init];
[plugin createMethodChannel:registrar];
[plugin createEventChannel:registrar];
[plugin createMessageChannel:registrar];
}
3、如果需要跳转原生页面则需拿到当前控制器
可通过下面方法实现
@property(strong, nonatomic) UIViewController *viewController;
+ (void)registerWithRegistrar:(NSObject<FlutterPluginRegistrar>*)registrar {
FlutterMethodChannel* channel = [FlutterMethodChannel
methodChannelWithName:@"flutter_rtmp_plugin"
binaryMessenger:[registrar messenger]];
UIViewController *viewController =
[UIApplication sharedApplication].delegate.window.rootViewController;
FlutterRtmpPlugin* instance = [[FlutterRtmpPlugin alloc] initWithViewController:viewController];
[registrar addMethodCallDelegate:instance channel:channel];
}
- (instancetype)initWithViewController:(UIViewController *)viewController {
self = [super init];
if (self) {
self.viewController = viewController;
}
return self;
}
- (void)handleMethodCall:(FlutterMethodCall*)call result:(FlutterResult)result {
if ([call.method isEqualToString:@"startLive"]) {
NSDictionary * dict = call.arguments;
NSLog(@"流地址是 %@",dict[@"url"]);
LFViewController *liveVC = [[LFViewController alloc] init];
liveVC.liveUrl = dict[@"url"];
liveVC.modalPresentationStyle = UIModalPresentationFullScreen;
[self.viewController presentViewController:liveVC animated:YES completion:nil];
}
else {
result(FlutterMethodNotImplemented);
}
}
Android端的书写
MethodChannel, 另外两种Channel参照iOS，两者类似
1、入口函数中创建MethodChannel
public void onAttachedToEngine(@NonNull FlutterPluginBinding flutterPluginBinding) {
final MethodChannel channel = new MethodChannel(flutterPluginBinding.getFlutterEngine().getDartExecutor(), "flutterplugintemp");
channel.setMethodCallHandler(this);
}
2、遵循两个协议
implements FlutterPlugin, MethodCallHandler
3、实现协议方法，在方法中写代码实现。
public void onMethodCall(@NonNull MethodCall call, @NonNull Result result) {
if(call.method.equals("startLive")){
Intent intent = new Intent(context,LivingActivity.class);
String url = call.argument("url");
intent.putExtra("url",url);
intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK );
context.startActivity(intent);
} else {
result.notImplemented();
}
注意事项
flutter 1.12版本之前的入口函数是
public static void registerWith(Registrar registrar) {
flutter 1.12版本以后是
public void onAttachedToEngine(@NonNull FlutterPluginBinding flutterPluginBinding) {
若果写错会收不到Flutter的方法回调
2、若果要跳转原生页面则需要拿到app的当前context或activity
可通过这种写法获取
//
private Context context;
public void onAttachedToEngine(@NonNull FlutterPluginBinding flutterPluginBinding) {
FlutterRtmpPlugin plugin = new FlutterRtmpPlugin();
plugin.context = flutterPluginBinding.getApplicationContext();
final MethodChannel channel = new MethodChannel(flutterPluginBinding.getFlutterEngine().getDartExecutor(), "flutter_rtmp_plugin");
channel.setMethodCallHandler(plugin);
}
public void onMethodCall(@NonNull MethodCall call, @NonNull Result result) {
if(call.method.equals("startLive")){
Intent intent = new Intent(context,LivingActivity.class);
String url = call.argument("url");
intent.putExtra("url",url);
intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK );
context.startActivity(intent);
} else {
result.notImplemented();
}
}
总结：
以上是plugin的基本使用，要想应付各种复杂的场景还需多参考google官方插件源码，来汲取养分。
比如 camera
