Fix memory leak in QQC1

When repeatedly creating a QQuickView, loading a QML file that imports
QQC1 and deleting the view again, we would leak memory that was
allocated as a consequence of QML type registration in
initializeEngine() callbacks that were called on every iteration.

After the limitation of namespacing in the registerTypes() callback of
QML module plugins has been lifted, we can move the type registrations
into registerTypes() where they belong and which is called only once.

Change-Id: I1d21b18dd060e169a1ee1095f5c5af7341443492
Reviewed-by: J-P Nurmi <jpnurmi@qt.io>
Reviewed-by: Mitch Curtis <mitch.curtis@qt.io>
Reviewed-by: Michael Winkelmann <michael.winkelmann@qt.io>

3 files changed, 8 insertions, 16 deletions

diff --git a/src/controls/plugin.cpp b/src/controls/plugin.cpp
index f78098ec..4eb6c466 100644
--- a/src/controls/plugin.cpp
+++ b/src/controls/plugin.cpp
@@ -149,11 +149,6 @@ void QtQuickControls1Plugin::registerTypes(const char *uri)
     const QString filesLocation = fileLocation();
     for (int i = 0; i < int(sizeof(qmldir)/sizeof(qmldir[0])); i++)
         qmlRegisterType(QUrl(filesLocation + "/" + qmldir[i].type + ".qml"), uri, qmldir[i].major, qmldir[i].minor, qmldir[i].type);
-}
-
-void QtQuickControls1Plugin::initializeEngine(QQmlEngine *engine, const char *uri)
-{
-    Q_UNUSED(uri);
 
     // Register private API. Note that to use these types outside of the
     // Qt Quick Controls module, both the public and private imports must be used.
@@ -185,6 +180,14 @@ void QtQuickControls1Plugin::initializeEngine(QQmlEngine *engine, const char *ur
 
 #ifdef QT_WIDGETS_LIB
     qmlRegisterType<QQuickStyleItem1>(private_uri, 1, 0, "StyleItem");
+#endif
+}
+
+void QtQuickControls1Plugin::initializeEngine(QQmlEngine *engine, const char *uri)
+{
+    Q_UNUSED(uri);
+
+#ifdef QT_WIDGETS_LIB
     engine->addImageProvider("__tablerow", new QQuickTableRowImageProvider1);
 #endif
     engine->addImageProvider("desktoptheme", new QQuickDesktopIconProvider1);
diff --git a/src/extras/plugin.cpp b/src/extras/plugin.cpp
index 5133a4ac..68d6ca16 100644
--- a/src/extras/plugin.cpp
+++ b/src/extras/plugin.cpp
@@ -99,22 +99,12 @@ void QtQuickExtrasPlugin::registerTypes(const char *uri)
 #if QT_CONFIG(picture)
     qmlRegisterType<QQuickPicture>(uri, 1, 4, "Picture");
 #endif
-}
 
-void QtQuickExtrasPlugin::initializeEngine(QQmlEngine *engine, const char *uri)
-{
-    Q_UNUSED(uri);
-    Q_UNUSED(engine);
     qmlRegisterType<QQuickMouseThief>("QtQuick.Extras.Private.CppUtils", 1, 0, "MouseThief");
     qmlRegisterType<QQuickCircularProgressBar>("QtQuick.Extras.Private.CppUtils", 1, 1, "CircularProgressBar");
     qmlRegisterType<QQuickFlatProgressBar>("QtQuick.Extras.Private.CppUtils", 1, 1, "FlatProgressBar");
     qmlRegisterSingletonType<QQuickMathUtils>("QtQuick.Extras.Private.CppUtils", 1, 0, "MathUtils", registerMathUtilsSingleton);
 
-#ifndef QT_STATIC
-    const QString prefix = baseUrl().toString();
-#else
-    const QString prefix = "qrc:/qt-project.org/imports/QtQuick/Extras";
-#endif
     const char *private_uri = "QtQuick.Extras.Private";
     qmlRegisterType(QUrl(prefix + "/Private/CircularButton.qml"), private_uri, 1, 0, "CircularButton");
     qmlRegisterType(QUrl(prefix + "/Private/CircularButtonStyleHelper.qml"), private_uri, 1, 0, "CircularButtonStyleHelper");
diff --git a/src/extras/plugin.h b/src/extras/plugin.h
index 05855f49..5f0a380e 100644
--- a/src/extras/plugin.h
+++ b/src/extras/plugin.h
@@ -54,7 +54,6 @@ public:
     explicit QtQuickExtrasPlugin(QObject *parent = 0);
 
     void registerTypes(const char *uri);
-    void initializeEngine(QQmlEngine *engine, const char *uri);
 };
 
 QT_END_NAMESPACE