Fix unknow device bug

git-svn-id: https://redmine.imt-atlantique.fr/svn/xaal/code/Python/branches/fork@1806 b32b6428-25c9-4566-ad07-03861ab6144f

apps/dashboard/xaal/dashboard/core/sio.py

@@ -31,8 +31,11 @@ def query_attributes(sid,addr):
 def refresh_attributes(sid,addrs):
     for addr in addrs:
         dev = xaal_core.get_device(str(addr))
-        msg = { 'address': dev.address,'attributes':dev.attributes}
-        socket.emit('event_attributeChanges',msg,room=sid)
+        if dev:
+            msg = { 'address': dev.address,'attributes':dev.attributes}
+            socket.emit('event_attributeChanges',msg,room=sid)
+        else:
+            print("Unknow device: %s" % addr)
 
 @socket.on('debug')
 def debug(sid):