- const set< shared_ptr<SignalData> > visible_data = get_visible_data();
- for (const shared_ptr<SignalData>& d : visible_data) {
+
+ vector< shared_ptr<SignalData> > data;
+ if (signals_.size() == 0)
+ return make_pair(0, 0);
+
+ data.push_back(signals_.front()->data());
+
+ for (const shared_ptr<SignalData>& d : data) {