Wait until parameter load complete for Mission Load

src/MissionManager/MissionManager.cc

@@ -45,8 +45,6 @@ MissionManager::MissionManager(Vehicle* vehicle)
     _ackTimeoutTimer->setInterval(_ackTimeoutMilliseconds);
     
     connect(_ackTimeoutTimer, &QTimer::timeout, this, &MissionManager::_ackTimeout);
-    
-    requestMissionItems();
 }
 
 MissionManager::~MissionManager()

src/Vehicle/Vehicle.cc

@@ -87,6 +87,7 @@ Vehicle::Vehicle(LinkInterface* link, int vehicleId, MAV_AUTOPILOT firmwareType,
     , _satelliteLock(0)
     , _updateCount(0)
     , _missionManager(NULL)
+    , _missionManagerInitialRequestComplete(false)
     , _armed(false)
     , _base_mode(0)
     , _custom_mode(0)
@@ -110,7 +111,8 @@ Vehicle::Vehicle(LinkInterface* link, int vehicleId, MAV_AUTOPILOT firmwareType,
     _firmwarePlugin = FirmwarePluginManager::instance()->firmwarePluginForAutopilot(_firmwareType, _vehicleType);
     _autopilotPlugin = AutoPilotPluginManager::instance()->newAutopilotPluginForVehicle(this);
     
-    connect(_autopilotPlugin, &AutoPilotPlugin::missingParametersChanged, this, &Vehicle::missingParametersChanged);
+    connect(_autopilotPlugin, &AutoPilotPlugin::parametersReadyChanged,     this, &Vehicle::_parametersReady);
+    connect(_autopilotPlugin, &AutoPilotPlugin::missingParametersChanged,   this, &Vehicle::missingParametersChanged);
 
     // Refresh timer
     connect(_refreshTimer, SIGNAL(timeout()), this, SLOT(_checkUpdate()));
@@ -1101,3 +1103,11 @@ void Vehicle::_mapTrajectoryStop()
 {
     _mapTrajectoryTimer.stop();
 }
+
+void Vehicle::_parametersReady(bool parametersReady)
+{
+    if (parametersReady && !_missionManagerInitialRequestComplete) {
+        _missionManagerInitialRequestComplete = true;
+        _missionManager->requestMissionItems();
+    }
+}

src/Vehicle/Vehicle.h

@@ -304,6 +304,7 @@ private slots:
     void _sendMessage(mavlink_message_t message);
     void _sendMessageMultipleNext(void);
     void _addNewMapTrajectoryPoint(void);
+    void _parametersReady(bool parametersReady);
 
     void _handleTextMessage                 (int newCount);
     /** @brief Attitude from main autopilot / system state */
@@ -409,7 +410,7 @@ private:
     int             _updateCount;
     
     MissionManager*     _missionManager;
-    QmlObjectListModel  _missionItems;
+    bool                _missionManagerInitialRequestComplete;
     
     bool    _armed;         ///< true: vehicle is armed
     uint8_t _base_mode;     ///< base_mode from HEARTBEAT