add serviceLost callback

android/src/main/java/eu/sndr/fluttermdnsplugin/FlutterMdnsPlugin.java

@@ -13,6 +13,7 @@
 import eu.sndr.fluttermdnsplugin.handlers.DiscoveryRunningHandler;
 import eu.sndr.fluttermdnsplugin.handlers.ServiceDiscoveredHandler;
 import eu.sndr.fluttermdnsplugin.handlers.ServiceResolvedHandler;
+import eu.sndr.fluttermdnsplugin.handlers.ServiceLostHandler;
 import io.flutter.plugin.common.EventChannel;
 import io.flutter.plugin.common.MethodCall;
 import io.flutter.plugin.common.MethodChannel;
@@ -48,6 +49,10 @@ public static void registerWith(Registrar registrar) {
     mResolvedHandler = new ServiceResolvedHandler();
     serviceResolved.setStreamHandler(mResolvedHandler);
 
+    EventChannel serviceLost = new EventChannel(r.messenger(), NAMESPACE + "/lost");
+    mLostHandler = new ServiceLostHandler();
+    serviceLost.setStreamHandler(mLostHandler);
+
     EventChannel discoveryRunning = new EventChannel(r.messenger(), NAMESPACE + "/running");
     mDiscoveryRunningHandler = new DiscoveryRunningHandler();
     discoveryRunning.setStreamHandler(mDiscoveryRunningHandler);
@@ -59,6 +64,7 @@ public static void registerWith(Registrar registrar) {
   private DiscoveryRunningHandler mDiscoveryRunningHandler;
   private ServiceDiscoveredHandler mDiscoveredHandler;
   private ServiceResolvedHandler mResolvedHandler;
+  private ServiceLostHandler mLostHandler;
 
   @Override
   public void onMethodCall(MethodCall call, Result result) {
@@ -147,6 +153,7 @@ public void onServiceResolved(NsdServiceInfo nsdServiceInfo) {
       @Override
       public void onServiceLost(NsdServiceInfo nsdServiceInfo) {
         Log.d(TAG, "Lost Service : " + nsdServiceInfo.toString());
+        mLostHandler.onServiceLost(ServiceToMap(nsdServiceInfo));
       }
     };
 

android/src/main/java/eu/sndr/fluttermdnsplugin/handlers/ServiceLostHandler.java

@@ -0,0 +1,23 @@
+package eu.sndr.fluttermdnsplugin.handlers;
+
+import java.util.Map;
+
+import io.flutter.plugin.common.EventChannel;
+
+public class ServiceLostHandler implements EventChannel.StreamHandler {
+
+    EventChannel.EventSink sink;
+    @Override
+    public void onListen(Object o, EventChannel.EventSink eventSink) {
+        sink = eventSink;
+    }
+
+    @Override
+    public void onCancel(Object o) {
+
+    }
+
+    public void onServiceLost(Map<String, Object> serviceInfoMap){
+        sink.success(serviceInfoMap);
+    }
+}

ios/Classes/FlutterMdnsPlugin.m

@@ -2,12 +2,14 @@
 #import "FlutterMdnsPlugin.h"
 #import "ServiceDiscoveredHandler.h"
 #import "ServiceResolvedHandler.h"
+#import "ServiceLostHandler.h"
 #import "DiscoveryRunningHandler.h"
 
 @interface FlutterMdnsPlugin ()
 
 @property(nonatomic, retain) ServiceDiscoveredHandler *serviceDiscoveredHandler;
 @property(nonatomic, retain) ServiceResolvedHandler *serviceResolvedHandler;
+@property(nonatomic, retain) ServiceLostHandler *serviceLostHandler;
 @property(nonatomic, retain) DiscoveryRunningHandler *discoveryRunningHandler;
 
 @property(nonatomic, retain) NSNetServiceBrowser *serviceBrowser;
@@ -38,6 +40,13 @@ + (void)registerWithRegistrar:(NSObject<FlutterPluginRegistrar>*)registrar {
     instance.serviceResolvedHandler = [[ServiceResolvedHandler alloc] init];
     [serviceResolved setStreamHandler:instance.serviceResolvedHandler];
 
+    FlutterEventChannel *serviceLost = [[FlutterEventChannel alloc]
+            initWithName:@"eu.sndr.mdns/lost"
+         binaryMessenger:registrar.messenger
+                   codec:[FlutterStandardMethodCodec sharedInstance]];
+    instance.serviceLostHandler = [[ServiceLostHandler alloc] init];
+    [serviceLost setStreamHandler:instance.serviceLostHandler];
+
     FlutterEventChannel *discoveryRunning = [[FlutterEventChannel alloc]
             initWithName:@"eu.sndr.mdns/running"
          binaryMessenger:registrar.messenger
@@ -158,6 +167,10 @@ - (void)netServiceBrowser:(NSNetServiceBrowser *)aNetServiceBrowser didFindServi
 - (void)netServiceBrowser:(NSNetServiceBrowser *)netServiceBrowser didRemoveService:(NSNetService *)aNetService moreComing:(BOOL)moreServicesComing
 {
     [self.services removeObject:aNetService];
+
+    [self.serviceLostHandler onServiceLost:
+        [self serviceToDictionary:aNetService]
+    ];
 }
 
 - (NSDictionary *) serviceToDictionary:(NSNetService *)aNetService withAddress:(NSString *)address  {

ios/Classes/ServiceLostHandler.h

@@ -0,0 +1,12 @@
+//
+// Created by brouwer on 23-11-18.
+//
+
+#import <Foundation/Foundation.h>
+#import <Flutter/Flutter.h>
+
+@interface ServiceLostHandler : NSObject <FlutterStreamHandler>
+- (void)onServiceLost:(NSDictionary *)serviceInfoMap;
+
+- (BOOL)isReady;
+@end

ios/Classes/ServiceLostHandler.m

@@ -0,0 +1,28 @@
+//
+// Created by brouwer on 23-11-18.
+//
+
+#import "ServiceLostHandler.h"
+
+@implementation ServiceLostHandler {
+    FlutterEventSink _eventSink;
+}
+
+- (FlutterError *_Nullable)onListenWithArguments:(id _Nullable)arguments eventSink:(FlutterEventSink)events {
+    _eventSink = events;
+    return nil;
+}
+
+- (FlutterError *_Nullable)onCancelWithArguments:(id _Nullable)arguments {
+    return nil;
+}
+
+- (void) onServiceLost:(NSDictionary *)serviceInfoMap {
+    _eventSink(serviceInfoMap);
+}
+
+- (BOOL) isReady {
+    return nil != _eventSink;
+}
+
+@end

lib/flutter_mdns_plugin.dart

@@ -60,11 +60,13 @@ class DiscoveryCallbacks{
   VoidCallback onDiscoveryStopped;
   ServiceInfoCallback onDiscovered;
   ServiceInfoCallback onResolved;
+  ServiceInfoCallback onLost;
   DiscoveryCallbacks({
     this.onDiscoveryStarted,
     this.onDiscoveryStopped,
     this.onDiscovered,
     this.onResolved,
+    this.onLost,
   });
 }
 
@@ -80,6 +82,9 @@ class FlutterMdnsPlugin {
   final EventChannel _serviceResolvedChannel =
   const EventChannel("$NAMESPACE/resolved");
 
+  final EventChannel _serviceLostChannel =
+  const EventChannel("$NAMESPACE/lost");
+
   final EventChannel _discoveryRunningChannel =
   const EventChannel("$NAMESPACE/running");
 
@@ -99,6 +104,11 @@ class FlutterMdnsPlugin {
         discoveryCallbacks.onDiscovered(ServiceInfo.fromMap(data));
       });
 
+      _serviceLostChannel.receiveBroadcastStream().listen((data) {
+        print("Service lost ${data.toString()}");
+        discoveryCallbacks.onLost(ServiceInfo.fromMap(data));
+      });
+
       _discoveryRunningChannel.receiveBroadcastStream().listen((running) {
         print("Discovery Running? $running");
         if (running && discoveryCallbacks.onDiscoveryStarted != null) {