Define shortcuts for Save & Discard buttons of message box that appea…

…rs when closing a document

src/Gui/Document.cpp

@@ -24,10 +24,12 @@
 #include "PreCompiled.h"
 
 #ifndef _PreComp_
+# include <QAbstractButton>
 # include <qapplication.h>
 # include <qdir.h>
 # include <qfileinfo.h>
 # include <QGLWidget>
+# include <QKeySequence>
 # include <qmessagebox.h>
 # include <qstatusbar.h>
 # include <boost/signals.hpp>
@@ -1203,6 +1205,22 @@ bool Document::canClose ()
         box.setInformativeText(QObject::tr("If you don't save, your changes will be lost."));
         box.setStandardButtons(QMessageBox::Discard | QMessageBox::Cancel | QMessageBox::Save);
         box.setDefaultButton(QMessageBox::Save);
+        box.setEscapeButton(QMessageBox::Cancel);
+
+        // add shortcuts
+        QAbstractButton* saveBtn = box.button(QMessageBox::Save);
+        if (saveBtn->shortcut().isEmpty()) {
+            QString text = saveBtn->text();
+            text.prepend(QLatin1Char('&'));
+            saveBtn->setShortcut(QKeySequence::mnemonic(text));
+        }
+
+        QAbstractButton* discardBtn = box.button(QMessageBox::Discard);
+        if (discardBtn->shortcut().isEmpty()) {
+            QString text = discardBtn->text();
+            text.prepend(QLatin1Char('&'));
+            discardBtn->setShortcut(QKeySequence::mnemonic(text));
+        }
 
         switch (box.exec())
         {