Protect QGeoMap pointer with QPointer

m_map inside QDeclarativeGeoMap is created, but also destroyed, by the
engine.
In some cases (dynamic QML object creation/destruction) the engine may
disappear before the Map.
This patch introduces a QPointer to prevent a dangling pointer

Change-Id: Ice3c57b4dbeb96ee8d7e4d401654b9085c105dec
Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>
Reviewed-by: Alex Blasche <alexander.blasche@qt.io>

4 files changed, 18 insertions, 17 deletions

diff --git a/src/location/declarativemaps/qdeclarativegeomap.cpp b/src/location/declarativemaps/qdeclarativegeomap.cpp
index ff34f1ea..35520227 100644
--- a/src/location/declarativemaps/qdeclarativegeomap.cpp
+++ b/src/location/declarativemaps/qdeclarativegeomap.cpp
@@ -278,17 +278,17 @@ void QDeclarativeGeoMap::onMapChildrenChanged()
 
             copyrights = m_copyrights.data();
 
-            connect(m_map, SIGNAL(copyrightsChanged(QImage)),
+            connect(m_map.data(), SIGNAL(copyrightsChanged(QImage)),
                     copyrights, SLOT(copyrightsChanged(QImage)));
-            connect(m_map, SIGNAL(copyrightsChanged(QImage)),
+            connect(m_map.data(), SIGNAL(copyrightsChanged(QImage)),
                     this,  SIGNAL(copyrightsChanged(QImage)));
 
-            connect(m_map, SIGNAL(copyrightsChanged(QString)),
+            connect(m_map.data(), SIGNAL(copyrightsChanged(QString)),
                     copyrights, SLOT(copyrightsChanged(QString)));
-            connect(m_map, SIGNAL(copyrightsChanged(QString)),
+            connect(m_map.data(), SIGNAL(copyrightsChanged(QString)),
                     this,  SIGNAL(copyrightsChanged(QString)));
 
-            connect(m_map, SIGNAL(copyrightsStyleSheetChanged(QString)),
+            connect(m_map.data(), SIGNAL(copyrightsStyleSheetChanged(QString)),
                     copyrights, SLOT(onCopyrightsStyleSheetChanged(QString)));
 
             connect(copyrights, SIGNAL(linkActivated(QString)),
@@ -724,7 +724,7 @@ void QDeclarativeGeoMap::onCameraCapabilitiesChanged(const QGeoCameraCapabilitie
 */
 void QDeclarativeGeoMap::mappingManagerInitialized()
 {
-    m_map = m_mappingManager->createMap(this);
+    m_map = QPointer<QGeoMap>(m_mappingManager->createMap(this));
 
     if (!m_map)
         return;
@@ -759,23 +759,23 @@ void QDeclarativeGeoMap::mappingManagerInitialized()
     m_copyrights = new QDeclarativeGeoMapCopyrightNotice(this);
     m_copyrights->onCopyrightsStyleSheetChanged(m_map->copyrightsStyleSheet());
 
-    connect(m_map, SIGNAL(copyrightsChanged(QImage)),
+    connect(m_map.data(), SIGNAL(copyrightsChanged(QImage)),
             m_copyrights.data(), SLOT(copyrightsChanged(QImage)));
-    connect(m_map, SIGNAL(copyrightsChanged(QImage)),
+    connect(m_map.data(), SIGNAL(copyrightsChanged(QImage)),
             this,  SIGNAL(copyrightsChanged(QImage)));
 
-    connect(m_map, SIGNAL(copyrightsChanged(QString)),
+    connect(m_map.data(), SIGNAL(copyrightsChanged(QString)),
             m_copyrights.data(), SLOT(copyrightsChanged(QString)));
-    connect(m_map, SIGNAL(copyrightsChanged(QString)),
+    connect(m_map.data(), SIGNAL(copyrightsChanged(QString)),
             this,  SIGNAL(copyrightsChanged(QString)));
 
-    connect(m_map, SIGNAL(copyrightsStyleSheetChanged(QString)),
+    connect(m_map.data(), SIGNAL(copyrightsStyleSheetChanged(QString)),
             m_copyrights.data(), SLOT(onCopyrightsStyleSheetChanged(QString)));
 
     connect(m_copyrights.data(), SIGNAL(linkActivated(QString)),
             this, SIGNAL(copyrightLinkActivated(QString)));
-    connect(m_map, &QGeoMap::sgNodeChanged, this, &QQuickItem::update);
-    connect(m_map, &QGeoMap::cameraCapabilitiesChanged, this, &QDeclarativeGeoMap::onCameraCapabilitiesChanged);
+    connect(m_map.data(), &QGeoMap::sgNodeChanged, this, &QQuickItem::update);
+    connect(m_map.data(), &QGeoMap::cameraCapabilitiesChanged, this, &QDeclarativeGeoMap::onCameraCapabilitiesChanged);
 
     // set visibility of copyright notice
     m_copyrights->setCopyrightsVisible(m_copyrightsVisible);
diff --git a/src/location/declarativemaps/qdeclarativegeomap_p.h b/src/location/declarativemaps/qdeclarativegeomap_p.h
index da430ce5..f08998e2 100644
--- a/src/location/declarativemaps/qdeclarativegeomap_p.h
+++ b/src/location/declarativemaps/qdeclarativegeomap_p.h
@@ -248,7 +248,7 @@ private:
     QList<QDeclarativeGeoMapType *> m_supportedMapTypes;
     QList<QDeclarativeGeoMapItemView *> m_mapViews;
     QQuickGeoMapGestureArea *m_gestureArea;
-    QGeoMap *m_map;
+    QPointer<QGeoMap> m_map;
     QPointer<QDeclarativeGeoMapCopyrightNotice> m_copyrights;
     QList<QPointer<QDeclarativeGeoMapItemBase> > m_mapItems;
     QList<QPointer<QDeclarativeGeoMapItemGroup> > m_mapItemGroups;
diff --git a/src/location/declarativemaps/qquickgeomapgesturearea.cpp b/src/location/declarativemaps/qquickgeomapgesturearea.cpp
index 412e33a1..3511226c 100644
--- a/src/location/declarativemaps/qquickgeomapgesturearea.cpp
+++ b/src/location/declarativemaps/qquickgeomapgesturearea.cpp
@@ -506,7 +506,7 @@ QQuickGeoMapGestureArea::QQuickGeoMapGestureArea(QDeclarativeGeoMap *map)
 /*!
     \internal
 */
-void QQuickGeoMapGestureArea::setMap(QGeoMap *map)
+void QQuickGeoMapGestureArea::setMap(QPointer<QGeoMap> map)
 {
     if (m_map || !map)
         return;
diff --git a/src/location/declarativemaps/qquickgeomapgesturearea_p.h b/src/location/declarativemaps/qquickgeomapgesturearea_p.h
index 13278651..320c0fbe 100644
--- a/src/location/declarativemaps/qquickgeomapgesturearea_p.h
+++ b/src/location/declarativemaps/qquickgeomapgesturearea_p.h
@@ -50,6 +50,7 @@
 
 #include <QtLocation/private/qlocationglobal_p.h>
 
+#include <QtCore/QPointer>
 #include <QtQuick/QQuickItem>
 #include <QTouchEvent>
 #include <QDebug>
@@ -175,7 +176,7 @@ public:
     void setMaximumZoomLevel(qreal max);
     qreal maximumZoomLevel() const;
 
-    void setMap(QGeoMap *map);
+    void setMap(QPointer<QGeoMap> map);
 
     bool preventStealing() const;
     void setPreventStealing(bool prevent);
@@ -264,7 +265,7 @@ private:
     void updateFlickParameters(const QPointF &pos);
 
 private:
-    QGeoMap *m_map;
+    QPointer<QGeoMap> m_map;
     QDeclarativeGeoMap *m_declarativeMap;
     bool m_enabled;