handle missing ROS for VideoStream

src/VideoStream/index.js

@@ -13,11 +13,13 @@ class VideoStream extends Component {
             url: hasUrl ? this.props.url : this.defaultImage
         };
 
-        this.props.ros.getTopics(function(infos){
-            if (undefined !== infos.topics.find(elem => elem === this.topic)) {
-                this.setState({url: 'http://localhost:8081/stream?topic=' + this.topic});
-            }
-          }.bind(this))
+        if (this.props.ros) {
+            this.props.ros.getTopics(function(infos){
+                if (undefined !== infos.topics.find(elem => elem === this.topic)) {
+                    this.setState({url: 'http://localhost:8081/stream?topic=' + this.topic});
+                }
+            }.bind(this))
+        }
     }
 
     handleSettingsChange(event) {