front: display simulation results only if a train is selected or get data is ready

Signed-off-by: Clara Ni <[email protected]>

Author: clarani

front/src/applications/operationalStudies/views/SimulationResults.tsx

@@ -116,6 +116,10 @@ const SimulationResults = ({
     }
   }, [extViewport]);
 
+  if (!selectedTrainSchedule && !projectionData) {
+    return null;
+  }
+
   return (
     <div className="simulation-results">
       {/* SIMULATION : STICKY BAR */}