From 8223ddb71047ef9c3802134617701e1f9b618448 Mon Sep 17 00:00:00 2001
From: Klaus Basan <klaus.basan@klausbasan.de>
Date: Thu, 28 Mar 2019 18:57:12 +0100
Subject: [PATCH] Checks to avoid crash during shutdown

---
 src/blackgui/components/logincomponent.cpp |  1 +
 src/blackgui/infoarea.cpp                  | 14 ++++++++------
 2 files changed, 9 insertions(+), 6 deletions(-)

diff --git a/src/blackgui/components/logincomponent.cpp b/src/blackgui/components/logincomponent.cpp
index 4ab729819..80899f5a3 100644
--- a/src/blackgui/components/logincomponent.cpp
+++ b/src/blackgui/components/logincomponent.cpp
@@ -671,6 +671,7 @@ namespace BlackGui
 
         void CLoginComponent::lookupOwnAircraftModel()
         {
+            if (!this->hasValidContexts()) { return; }
             if (!sGui->getIContextSimulator()->isSimulatorAvailable()) { return; }
             const CAircraftModel model(sGui->getIContextOwnAircraft()->getOwnAircraft().getModel());
             this->onSimulatorModelChanged(model);
diff --git a/src/blackgui/infoarea.cpp b/src/blackgui/infoarea.cpp
index 8a8279141..70cd22b1b 100644
--- a/src/blackgui/infoarea.cpp
+++ b/src/blackgui/infoarea.cpp
@@ -541,7 +541,7 @@ namespace BlackGui
             }
         }
 
-        emit changedWholeInfoAreaFloating(floating);
+        emit this->changedWholeInfoAreaFloating(floating);
     }
 
     void CInfoArea::tabifyAllWidgets()
@@ -601,9 +601,9 @@ namespace BlackGui
                 // South does not have any effect
                 m_tabBar->setShape(QTabBar::TriangularSouth);
 
-                // signals
-                connect(m_tabBar, &QTabBar::tabBarDoubleClicked, this, &CInfoArea::onTabBarDoubleClicked);
-                connect(m_tabBar, &QTabBar::currentChanged, this, &CInfoArea::onTabBarIndexChanged);
+                // signals, use Qt::QueuedConnection to avoid issues during shutdown
+                connect(m_tabBar, &QTabBar::tabBarDoubleClicked, this, &CInfoArea::onTabBarDoubleClicked, Qt::QueuedConnection);
+                connect(m_tabBar, &QTabBar::currentChanged,      this, &CInfoArea::onTabBarIndexChanged,  Qt::QueuedConnection);
             }
             else
             {
@@ -657,15 +657,16 @@ namespace BlackGui
 
     void CInfoArea::emitInfoAreaStatus()
     {
+        if (!sGui || sGui->isShuttingDown()) { return; } // avoid access to deleted components
         const int sia = this->getSelectedDockInfoAreaIndex();
         const QList<int> floating = this->getAreaIndexesDockedOrFloating(true);
         const QList<int> docked = this->getAreaIndexesDockedOrFloating(false);
-        emit changedInfoAreaStatus(sia, docked, floating);
+        emit this->changedInfoAreaStatus(sia, docked, floating);
     }
 
     void CInfoArea::onTabBarIndexChanged(int tabBarIndex)
     {
-        emit changedInfoAreaTabBarIndex(tabBarIndex);
+        emit this->changedInfoAreaTabBarIndex(tabBarIndex);
         emitInfoAreaStatus();
     }
 
@@ -804,6 +805,7 @@ namespace BlackGui
     {
         if (m_tabBar)
         {
+            if (!sGui || sGui->isShuttingDown()) { return; }
             const QString qss = sGui->getStyleSheetUtility().style(CStyleSheetUtility::fileNameDockWidgetTab());
             m_tabBar->setStyleSheet(qss);
         }