From 34edc2345c4ef1b6996800b294deb53d5fd0a18d Mon Sep 17 00:00:00 2001
From: volansystech <samir.thaker@volansys.com>
Date: Tue, 9 May 2017 22:07:32 +0530
Subject: [PATCH] Bug 4255: When you are in HMD and you go to file menu quit,
 it crashes and you have no menus when you come back. Fixed NPE of buttonProxy
 while doing addButtonProxyToQmlTablet on quitting the application.

---
 libraries/script-engine/src/TabletScriptingInterface.cpp | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/libraries/script-engine/src/TabletScriptingInterface.cpp b/libraries/script-engine/src/TabletScriptingInterface.cpp
index 139fe0552d..644f1e6f0c 100644
--- a/libraries/script-engine/src/TabletScriptingInterface.cpp
+++ b/libraries/script-engine/src/TabletScriptingInterface.cpp
@@ -250,6 +250,10 @@ static void addButtonProxyToQmlTablet(QQuickItem* qmlTablet, TabletButtonProxy*
     if (QThread::currentThread() != qmlTablet->thread()) {
         connectionType = Qt::BlockingQueuedConnection;
     }
+	if (buttonProxy == NULL){
+		qCCritical(scriptengine) << "TabletScriptingInterface addButtonProxyToQmlTablet buttonProxy is NULL";
+		return;
+	}
     bool hasResult = QMetaObject::invokeMethod(qmlTablet, "addButtonProxy", connectionType,
                                                Q_RETURN_ARG(QVariant, resultVar), Q_ARG(QVariant, buttonProxy->getProperties()));
     if (!hasResult) {