From 4db83230ce94b966efdfe07553d368be68a6e893 Mon Sep 17 00:00:00 2001
From: Brad Davis <bdavis@saintandreas.org>
Date: Fri, 27 Apr 2018 08:09:31 -0700
Subject: [PATCH] Fix bad virtual cast on qml surface destruction

---
 libraries/ui/src/ui/OffscreenQmlSurface.cpp | 23 +++++++++++++--------
 libraries/ui/src/ui/OffscreenQmlSurface.h   |  4 +++-
 2 files changed, 17 insertions(+), 10 deletions(-)

diff --git a/libraries/ui/src/ui/OffscreenQmlSurface.cpp b/libraries/ui/src/ui/OffscreenQmlSurface.cpp
index 43b573a169..b3c1c486e9 100644
--- a/libraries/ui/src/ui/OffscreenQmlSurface.cpp
+++ b/libraries/ui/src/ui/OffscreenQmlSurface.cpp
@@ -223,6 +223,17 @@ void AudioHandler::run() {
     qDebug() << "QML Audio changed to " << _newTargetDevice;
 }
 
+OffscreenQmlSurface::~OffscreenQmlSurface() {
+    clearFocusItem();
+}
+
+void OffscreenQmlSurface::clearFocusItem() {
+    if (_currentFocusItem) {
+        disconnect(_currentFocusItem, &QObject::destroyed, this, &OffscreenQmlSurface::focusDestroyed);
+    }
+    _currentFocusItem = nullptr;
+}
+
 void OffscreenQmlSurface::initializeEngine(QQmlEngine* engine) {
     Parent::initializeEngine(engine);
     new QQmlFileSelector(engine);
@@ -545,17 +556,15 @@ bool OffscreenQmlSurface::handlePointerEvent(const PointerEvent& event, class QT
 }
 
 void OffscreenQmlSurface::focusDestroyed(QObject* obj) {
-    if (_currentFocusItem) {
-        disconnect(_currentFocusItem, &QObject::destroyed, this, &OffscreenQmlSurface::focusDestroyed);
-    }
-    _currentFocusItem = nullptr;
+    clearFocusItem();
 }
 
 void OffscreenQmlSurface::onFocusObjectChanged(QObject* object) {
+    clearFocusItem();
+
     QQuickItem* item = static_cast<QQuickItem*>(object);
     if (!item) {
         setFocusText(false);
-        _currentFocusItem = nullptr;
         return;
     }
 
@@ -563,10 +572,6 @@ void OffscreenQmlSurface::onFocusObjectChanged(QObject* object) {
     qApp->sendEvent(object, &query);
     setFocusText(query.value(Qt::ImEnabled).toBool());
 
-    if (_currentFocusItem) {
-        disconnect(_currentFocusItem, &QObject::destroyed, this, 0);
-    }
-
     // Raise and lower keyboard for QML text fields.
     // HTML text fields are handled in emitWebEvent() methods - testing READ_ONLY_PROPERTY prevents action for HTML files.
     const char* READ_ONLY_PROPERTY = "readOnly";
diff --git a/libraries/ui/src/ui/OffscreenQmlSurface.h b/libraries/ui/src/ui/OffscreenQmlSurface.h
index 9fa86f12a3..b95a8f117d 100644
--- a/libraries/ui/src/ui/OffscreenQmlSurface.h
+++ b/libraries/ui/src/ui/OffscreenQmlSurface.h
@@ -22,7 +22,8 @@ class OffscreenQmlSurface : public hifi::qml::OffscreenSurface {
     Q_OBJECT
     Q_PROPERTY(bool focusText READ isFocusText NOTIFY focusTextChanged)
 public:
-    
+    ~OffscreenQmlSurface();
+
     static void addWhitelistContextHandler(const std::initializer_list<QUrl>& urls, const QmlContextCallback& callback);
     static void addWhitelistContextHandler(const QUrl& url, const QmlContextCallback& callback) { addWhitelistContextHandler({ { url } }, callback); };
 
@@ -58,6 +59,7 @@ public slots:
     void sendToQml(const QVariant& message);
 
 protected:
+    void clearFocusItem();
     void setFocusText(bool newFocusText);
     void initializeEngine(QQmlEngine* engine) override;
     void onRootContextCreated(QQmlContext* qmlContext) override;