Update README.md

Author: kavindaperera

README.md

@@ -129,6 +129,16 @@ You can either implement `ConnectionListener` interface or create an [`Anonymous
 // Anonymous Class
 ConnectionListener connectionListener = new ConnectionListener() {
 
+      @override
+      public void onStarted() {
+
+      }
+      
+      @override
+      public void onStartError(String message, int errorCode); {
+
+      }
+
       @override
       public void onDeviceDiscovered(Device device) {
 
@@ -168,6 +178,16 @@ MessageListener MessageListener = new MessageListener() {
       public void onBroadcastMessageReceived(Message message) {
 
       }
+      
+      @override
+      public void onMessageFailed(Message message, MessageException exception) {
+
+      }
+      
+      @override
+      public void onMessageSent(Message message) {
+
+      }
 
 }
 ```