From b36686e5867803beda8fc1539373eb1c6f20a61b Mon Sep 17 00:00:00 2001
From: wmayer <wmayer@users.sourceforge.net>
Date: Mon, 17 Jul 2017 11:11:58 +0200
Subject: [PATCH] calling close() causes the MDI view to get deleted as soon as
 possible while deleteLater() waits until the GUI is responsive

---
 src/Gui/Document.cpp |  2 ++
 src/Gui/MDIView.cpp  | 11 +++++++----
 2 files changed, 9 insertions(+), 4 deletions(-)

diff --git a/src/Gui/Document.cpp b/src/Gui/Document.cpp
index dbee2e6e24d1..a8869dfe6aea 100644
--- a/src/Gui/Document.cpp
+++ b/src/Gui/Document.cpp
@@ -1204,6 +1204,8 @@ bool Document::isLastView(void)
  */
 bool Document::canClose ()
 {
+    if (d->_isClosing)
+        return true;
     if (!getDocument()->isClosable()) {
         QMessageBox::warning(getActiveView(),
             QObject::tr("Document not closable"),
diff --git a/src/Gui/MDIView.cpp b/src/Gui/MDIView.cpp
index c069717035ea..6bf2aef74a48 100644
--- a/src/Gui/MDIView.cpp
+++ b/src/Gui/MDIView.cpp
@@ -92,10 +92,13 @@ void MDIView::deleteSelf()
     // #0001023: Crash when quitting after using Windows > Tile
     // Use deleteLater() instead of delete operator.
     QWidget* parent = this->parentWidget();
-    if (qobject_cast<QMdiSubWindow*>(parent))
-        parent->deleteLater();
-    else
-        this->deleteLater();
+    if (qobject_cast<QMdiSubWindow*>(parent)) {
+        // https://forum.freecadweb.org/viewtopic.php?f=22&t=23070
+        parent->close();
+    }
+    else {
+        this->close();
+    }
 
     // detach from document
     if (_pcDocument)