Merge branch 'main' of http://git.mcxa.cn:88/LiXiaoqi/roslib_dart

lib/core/topic.dart

@@ -119,33 +119,43 @@ class Topic {
     }
   }
 
+  
+
   /// Unsubscribe from the topic.
   Future<void> unsubscribe() async {
     if (subscribeId != null) {
       // Send the request and reset the subscription variables.
-      await safeSend(Request(
+      await safeSend(unsubscribeReq());
-        op: 'unsubscribe',
-        id: subscribeId,
-        topic: name,
-      ));
       // await ros.requestUnsubscribe(id);
       subscription = null;
       subscribeId = null;
     }
   }
 
+  Request unsubscribeReq() {
+    return Request(
+      op: 'unsubscribe',
+      id: subscribeId,
+      topic: name,
+    );
+  }
+
   /// Publish a [message] to the topic.
   Future<void> publish(dynamic message) async {
     // Advertise the topic and then send the publish request.
     await advertise();
     publishId = ros.requestPublisher(name);
-    await safeSend(Request(
+    await safeSend(publishReq(message));
+  }
+
+  Request publishReq(dynamic message) {
+    return Request(
       op: 'publish',
       topic: name,
       id: publishId,
       msg: message,
       latch: latch,
-    ));
+    );
   }
 
   /// Advertise the topic.
@@ -153,17 +163,21 @@ class Topic {
     if (!isAdvertised) {
       // Send the advertisement request.
       advertiseId = ros.requestAdvertiser(name);
-      await safeSend(Request(
+      await safeSend(advertiseReq());
+      // If the ROS connection closes show that we're not advertising anymore.
+      watchForClose();
+    }
+  }
+
+  Request advertiseReq() {
+    return Request(
       op: 'advertise',
       id: advertiseId,
       type: type,
       topic: name,
       latch: latch,
       queueSize: queueSize,
-      ));
+    );
-      // If the ROS connection closes show that we're not advertising anymore.
-      watchForClose();
-    }
   }
 
   /// Wait for the connection to close and then reset advertising variables.
@@ -187,6 +201,8 @@ class Topic {
     }
   }
 
+
+
   /// Safely send a [message] to ROS.
   Future<void> safeSend(Request message) async {
     // Send the message but if we're not connected and the [reconnectOnClose] flag