Defer joystick probe until after MainWindow is created

src/Joystick/JoystickManager.cc

@@ -53,7 +53,10 @@ void JoystickManager::setToolbox(QGCToolbox *toolbox)
     _multiVehicleManager = _toolbox->multiVehicleManager();
 
     QQmlEngine::setObjectOwnership(this, QQmlEngine::CppOwnership);
+}
 
+void JoystickManager::discoverJoysticks()
+{
 #ifdef __sdljoystick__
     _name2JoystickMap = JoystickSDL::discover(_multiVehicleManager);
 #elif defined(__android__)

src/Joystick/JoystickManager.h

@@ -48,6 +48,9 @@ public:
     // Override from QGCTool
     virtual void setToolbox(QGCToolbox *toolbox);
 
+public slots:
+    void discoverJoysticks();
+
 signals:
     void activeJoystickChanged(Joystick* joystick);
     void activeJoystickNameChanged(const QString& name);

src/QGCApplication.cc

@@ -429,6 +429,9 @@ bool QGCApplication::_initForNormalAppBoot(void)
     // Load known link configurations
     toolbox()->linkManager()->loadLinkConfigurationList();
 
+    // Probe for joysticks - TODO: manage on a timer or use events to deal with hotplug
+    toolbox()->joystickManager()->discoverJoysticks();
+
     if (_settingsUpgraded) {
         settings.clear();
         settings.setValue(_settingsVersionKey, QGC_SETTINGS_VERSION);