when param widget is loaded we only want to re-request the whole param list if we don't already have one

src/uas/UASParameterCommsMgr.cc

@@ -60,6 +60,15 @@ void UASParameterCommsMgr::loadParamCommsSettings()
 }
 
 
+void UASParameterCommsMgr::requestParameterListIfEmpty()
+{
+    int totalOnboard = paramDataModel->countOnboardParams();
+    if (totalOnboard < 2) { //TODO arbitrary constant, maybe 0 is OK?
+        requestParameterList();
+    }
+}
+
+
 
 /**
  * Send a request to deliver the list of onboard parameters

src/uas/UASParameterCommsMgr.h

@@ -72,6 +72,8 @@ public slots:
 
     /** @brief Request list of parameters from MAV */
     virtual void requestParameterList();
+    /** @brief Request a list of params onboard the MAV if the onboard param list we have is empty */
+    virtual void requestParameterListIfEmpty();
 
     /** @brief Check for missing parameters */
     virtual void retransmissionGuardTick();

src/uas/UASParameterDataModel.cc

@@ -20,15 +20,28 @@ UASParameterDataModel::UASParameterDataModel(QObject *parent) :
 
 int UASParameterDataModel::countPendingParams()
 {
-    int totalPending = 0;
+    int total = 0;
     QMap<int, QMap<QString, QVariant>*>::iterator i;
     for (i = pendingParameters.begin(); i != pendingParameters.end(); ++i) {
         // Iterate through the parameters of the component
         QMap<QString, QVariant>* paramList = i.value();
-        totalPending += paramList->count();
+        total += paramList->count();
     }
 
-    return totalPending;
+    return total;
+}
+
+int UASParameterDataModel::countOnboardParams()
+{
+    int total = 0;
+    QMap<int, QMap<QString, QVariant>*>::iterator i;
+    for (i = onboardParameters.begin(); i != onboardParameters.end(); ++i) {
+        // Iterate through the parameters of the component
+        QMap<QString, QVariant>* paramList = i.value();
+        total += paramList->count();
+    }
+
+    return total;
 }
 
 

src/uas/UASParameterDataModel.h

@@ -69,8 +69,10 @@ public:
    }
 
     /** @brief return a count of all pending parameters */
-    int countPendingParams();
+    virtual int countPendingParams();
 
+    /** @brief return a count of all onboard parameters we've received */
+    virtual int countOnboardParams();
 
     virtual void writeOnboardParamsToStream(QTextStream &stream, const QString& uasName);
     virtual void readUpdateParamsFromStream(QTextStream &stream);

src/ui/QGCPX4VehicleConfig.cc

@@ -802,7 +802,7 @@ void QGCPX4VehicleConfig::loadConfig()
     }
     doneLoadingConfig = true;
     //Config is finished, lets do a parameter request to ensure none are missed if someone else started requesting before we were finished.
-    mav->getParamCommsMgr()->requestParameterList();
+    paramCommsMgr->requestParameterListIfEmpty();
 }
 
 void QGCPX4VehicleConfig::setActiveUAS(UASInterface* active)

src/ui/QGCVehicleConfig.cc

@@ -791,7 +791,7 @@ void QGCVehicleConfig::loadConfig()
     mav->getParamManager()->setParamDescriptions(paramTooltips);
     doneLoadingConfig = true;
     //Config is finished, lets do a parameter request to ensure none are missed if someone else started requesting before we were finished.
-    mav->getParamCommsMgr()->requestParameterList();
+    mav->getParamCommsMgr()->requestParameterListIfEmpty();
 }
 
 void QGCVehicleConfig::setActiveUAS(UASInterface* active)