From 6f1fb20b1ccb4aa863135f45ab73199350b4d78c Mon Sep 17 00:00:00 2001
From: Klaus Basan <klaus.basan@klausbasan.de>
Date: Thu, 11 Apr 2019 02:07:44 +0200
Subject: [PATCH] Ref T596, do not call shutdown if close is called, as close
 already calls shutdown

---
 src/blackgui/guiapplication.cpp | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/src/blackgui/guiapplication.cpp b/src/blackgui/guiapplication.cpp
index ab42b7460..56c579a87 100644
--- a/src/blackgui/guiapplication.cpp
+++ b/src/blackgui/guiapplication.cpp
@@ -695,9 +695,14 @@ namespace BlackGui
         {
             // a close event might already trigger a shutdown
             if (!sGui || sGui->isShuttingDown()) { return; }
+            if (!this->mainApplicationWidget()) { return; }
             this->mainApplicationWidget()->close();
-            this->gracefulShutdown();
-        });
+
+            // T596, do not shutdown here, as close can be canceled
+            // if shutdown is called, there is no way back
+            // this->gracefulShutdown();
+        },
+        Qt::QueuedConnection);
         Q_ASSERT_X(c, Q_FUNC_INFO, "Connect failed");
         Q_UNUSED(c);
     }