From 8c951842d81a73c1fd6712701723430584d1a497 Mon Sep 17 00:00:00 2001 From: Andrew den Exter Date: Wed, 28 Mar 2012 16:30:50 +1000 Subject: [PATCH] Improve detection of deleted VisualDataModel items. The data object for each delegate object has a pointer guard with a virtual objectDestroyed() function, that's a better tool for detecting deletion than the destructor of a child object. Change-Id: Iad1516e3daeb5e019ece6c3b2eb65da768cf43cb Reviewed-by: Bea Lam Reviewed-by: Martin Jones --- src/quick/items/qquickvisualdatamodel.cpp | 83 ++++++++++++++++------------- src/quick/items/qquickvisualdatamodel_p_p.h | 35 +++--------- 2 files changed, 54 insertions(+), 64 deletions(-) diff --git a/src/quick/items/qquickvisualdatamodel.cpp b/src/quick/items/qquickvisualdatamodel.cpp index 417d50e..7f80fa0 100644 --- a/src/quick/items/qquickvisualdatamodel.cpp +++ b/src/quick/items/qquickvisualdatamodel.cpp @@ -151,13 +151,15 @@ QQuickVisualDataModel::~QQuickVisualDataModel() Q_D(QQuickVisualDataModel); foreach (QQuickVisualDataModelItem *cacheItem, d->m_cache) { - // If the object holds the last reference to the cache item deleting it will also - // delete the cache item, temporarily increase the reference count to avoid this. - cacheItem->scriptRef += 1; - delete cacheItem->object; - cacheItem->scriptRef -= 1; + if (QObject *object = cacheItem->object()) { + // Clear the guard before deleting the object so it doesn't decrement scriptRef and + // potentially delete the cacheItem itself. + cacheItem->setObject(0); + cacheItem->scriptRef -= 1; + + delete object; + } cacheItem->objectRef = 0; - cacheItem->object = 0; if (!cacheItem->isReferenced()) delete cacheItem; } @@ -438,11 +440,12 @@ QQuickVisualDataModel::ReleaseFlags QQuickVisualDataModelPrivate::release(QObjec destroy(object); if (QQuickItem *item = qobject_cast(object)) emitDestroyingItem(item); - cacheItem->object = 0; + cacheItem->setObject(0); if (cacheItem->incubationTask) { releaseIncubator(cacheItem->incubationTask); cacheItem->incubationTask = 0; } + cacheItem->Dispose(); stat |= QQuickVisualModel::Destroyed; } else { stat |= QQuickVisualDataModel::Referenced; @@ -482,13 +485,14 @@ void QQuickVisualDataModel::cancel(int index) d->releaseIncubator(cacheItem->incubationTask); cacheItem->incubationTask = 0; } - if (cacheItem->object && !cacheItem->isObjectReferenced()) { - d->destroy(cacheItem->object); - if (QQuickPackage *package = qobject_cast(cacheItem->object)) + if (cacheItem->object() && !cacheItem->isObjectReferenced()) { + d->destroy(cacheItem->object()); + if (QQuickPackage *package = qobject_cast(cacheItem->object())) d->emitDestroyingPackage(package); - else if (QQuickItem *item = qobject_cast(cacheItem->object)) + else if (QQuickItem *item = qobject_cast(cacheItem->object())) d->emitDestroyingItem(item); - cacheItem->object = 0; + cacheItem->setObject(0); + cacheItem->Dispose(); } if (!cacheItem->isReferenced()) { d->m_compositor.clearFlags(Compositor::Cache, it.cacheIndex, 1, Compositor::CacheFlag); @@ -748,13 +752,14 @@ void QQuickVisualDataModelPrivate::incubatorStatusChanged(QVDMIncubationTask *in if (status == QQmlIncubator::Ready) { incubationTask->incubating = 0; releaseIncubator(incubationTask); - if (QQuickPackage *package = qobject_cast(cacheItem->object)) + if (QQuickPackage *package = qobject_cast(cacheItem->object())) emitCreatedPackage(cacheItem, package); - else if (QQuickItem *item = qobject_cast(cacheItem->object)) + else if (QQuickItem *item = qobject_cast(cacheItem->object())) emitCreatedItem(cacheItem, item); } else if (status == QQmlIncubator::Error) { delete incubationTask->incubatingContext; incubationTask->incubatingContext = 0; + cacheItem->scriptRef -= 1; if (!cacheItem->isReferenced()) { int cidx = m_cache.indexOf(cacheItem); if (cidx >= 0) { @@ -777,18 +782,18 @@ void QVDMIncubationTask::setInitialState(QObject *o) void QQuickVisualDataModelPrivate::setInitialState(QVDMIncubationTask *incubationTask, QObject *o) { QQuickVisualDataModelItem *cacheItem = incubationTask->incubating; - cacheItem->object = o; - QQml_setParent_noEvent(incubationTask->incubatingContext, cacheItem->object); + cacheItem->setObject(o); + QQml_setParent_noEvent(incubationTask->incubatingContext, cacheItem->object()); incubationTask->incubatingContext = 0; - cacheItem->attached = QQuickVisualDataModelAttached::properties(cacheItem->object); + cacheItem->attached = QQuickVisualDataModelAttached::properties(cacheItem->object()); cacheItem->attached->setCacheItem(cacheItem); new QQuickVisualDataModelAttachedMetaObject(cacheItem->attached, m_cacheMetaType); cacheItem->attached->emitChanges(); - if (QQuickPackage *package = qobject_cast(cacheItem->object)) + if (QQuickPackage *package = qobject_cast(cacheItem->object())) emitInitPackage(cacheItem, package); - else if (QQuickItem *item = qobject_cast(cacheItem->object)) + else if (QQuickItem *item = qobject_cast(cacheItem->object())) emitInitItem(cacheItem, item); } @@ -824,23 +829,23 @@ QObject *QQuickVisualDataModelPrivate::object(Compositor::Group group, int index // previously requested async - now needed immediately cacheItem->incubationTask->forceCompletion(); } - } else if (!cacheItem->object) { + } else if (!cacheItem->object()) { + cacheItem->scriptRef += 1; + QVDMIncubationTask *incubator = new QVDMIncubationTask(this, asynchronous ? QQmlIncubator::Asynchronous : QQmlIncubator::AsynchronousIfNested); cacheItem->incubationTask = incubator; QQmlContext *creationContext = m_delegate->creationContext(); - QQmlContext *rootContext = new QQuickVisualDataModelContext( - cacheItem, creationContext ? creationContext : m_context); + QQmlContext *rootContext = new QQmlContext(creationContext ? creationContext : m_context); QQmlContext *ctxt = rootContext; + ctxt->setContextObject(cacheItem); if (m_adaptorModel.hasProxyObject()) { if (QQuickVisualAdaptorModelProxyInterface *proxy = qobject_cast(cacheItem)) { + ctxt = new QQmlContext(ctxt, ctxt); ctxt->setContextObject(proxy->proxiedObject()); - ctxt = new QQuickVisualDataModelContext(cacheItem, ctxt, ctxt); } } - ctxt->setContextObject(cacheItem); - incubator->incubating = cacheItem; incubator->incubatingContext = rootContext; m_delegate->create(*incubator, ctxt, m_context); @@ -848,9 +853,9 @@ QObject *QQuickVisualDataModelPrivate::object(Compositor::Group group, int index if (index == m_compositor.count(group) - 1 && m_adaptorModel.canFetchMore()) QCoreApplication::postEvent(q, new QEvent(QEvent::UpdateRequest)); - if (cacheItem->object && reference) + if (cacheItem->object() && reference) cacheItem->referenceObject(); - return cacheItem->object; + return cacheItem->object(); } /* @@ -1119,13 +1124,14 @@ void QQuickVisualDataModelPrivate::itemsRemoved( } else { for (; cacheIndex < remove.cacheIndex + remove.count - removedCache; ++cacheIndex) { QQuickVisualDataModelItem *cacheItem = m_cache.at(cacheIndex); - if (remove.inGroup(Compositor::Persisted) && cacheItem->objectRef == 0 && cacheItem->object) { - destroy(cacheItem->object); - if (QQuickPackage *package = qobject_cast(cacheItem->object)) + if (remove.inGroup(Compositor::Persisted) && cacheItem->objectRef == 0 && cacheItem->object()) { + destroy(cacheItem->object()); + if (QQuickPackage *package = qobject_cast(cacheItem->object())) emitDestroyingPackage(package); - else if (QQuickItem *item = qobject_cast(cacheItem->object)) + else if (QQuickItem *item = qobject_cast(cacheItem->object())) emitDestroyingItem(item); - cacheItem->object = 0; + cacheItem->setObject(0); + cacheItem->scriptRef -= 1; } if (!cacheItem->isReferenced()) { m_compositor.clearFlags(Compositor::Cache, cacheIndex, 1, Compositor::CacheFlag); @@ -1281,7 +1287,7 @@ void QQuickVisualDataModelPrivate::emitChanges() QQuickVisualDataGroupPrivate::get(m_groups[i])->emitModelUpdated(reset); foreach (QQuickVisualDataModelItem *cacheItem, m_cache) { - if (cacheItem->object && cacheItem->attached) + if (cacheItem->object() && cacheItem->attached) cacheItem->attached->emitChanges(); } } @@ -1625,7 +1631,6 @@ v8::Handle QQuickVisualDataModelItemMetaType::get_index( QQuickVisualDataModelItem::QQuickVisualDataModelItem( QQuickVisualDataModelItemMetaType *metaType, int modelIndex) : QV8ObjectResource(metaType->v8Engine) - , object(0) , metaType(metaType) , attached(0) , objectRef(0) @@ -1641,7 +1646,7 @@ QQuickVisualDataModelItem::~QQuickVisualDataModelItem() { Q_ASSERT(scriptRef == 0); Q_ASSERT(objectRef == 0); - Q_ASSERT(!object); + Q_ASSERT(!object()); Q_ASSERT(indexHandle.IsEmpty()); Q_ASSERT(modelHandle.IsEmpty()); @@ -1670,6 +1675,12 @@ void QQuickVisualDataModelItem::Dispose() delete this; } +void QQuickVisualDataModelItem::objectDestroyed(QObject *) +{ + attached = 0; + Dispose(); +} + //--------------------------------------------------------------------------- QQuickVisualDataModelAttachedMetaObject::QQuickVisualDataModelAttachedMetaObject( @@ -2288,7 +2299,7 @@ void QQuickVisualDataGroup::resolve(QQmlV8Function *args) Q_ASSERT(model->m_cache.count() == model->m_compositor.count(Compositor::Cache)); } else { cacheItem->resolveIndex(model->m_adaptorModel, resolvedIndex); - if (cacheItem->object) + if (cacheItem->object()) cacheItem->attached->emitUnresolvedChanged(); } diff --git a/src/quick/items/qquickvisualdatamodel_p_p.h b/src/quick/items/qquickvisualdatamodel_p_p.h index d539c49..5fd99d0 100644 --- a/src/quick/items/qquickvisualdatamodel_p_p.h +++ b/src/quick/items/qquickvisualdatamodel_p_p.h @@ -103,7 +103,7 @@ public: class QQuickVisualAdaptorModel; class QVDMIncubationTask; -class QQuickVisualDataModelItem : public QObject, public QV8ObjectResource +class QQuickVisualDataModelItem : public QObject, public QV8ObjectResource, public QQmlGuard { Q_OBJECT Q_PROPERTY(int index READ modelIndex NOTIFY modelIndexChanged) @@ -135,11 +135,6 @@ public: virtual void setValue(const QString &role, const QVariant &value) { Q_UNUSED(role); Q_UNUSED(value); } virtual bool resolveIndex(const QQuickVisualAdaptorModel &, int) { return false; } -Q_SIGNALS: - void modelIndexChanged(); - -public: - QQmlGuard object; QQuickVisualDataModelItemMetaType * const metaType; QQuickVisualDataModelAttached *attached; v8::Persistent indexHandle; @@ -150,6 +145,12 @@ public: int groups; int index[QQuickListCompositor::MaximumGroupCount]; QVDMIncubationTask *incubationTask; + +Q_SIGNALS: + void modelIndexChanged(); + +protected: + void objectDestroyed(QObject *); }; @@ -394,28 +395,6 @@ private: QQuickVisualDataModelItemMetaType *metaType; }; -class QQuickVisualDataModelContext : public QQmlContext -{ - Q_OBJECT -public: - QQuickVisualDataModelContext( - QQuickVisualDataModelItem *cacheItem, - QQmlContext *parentContext, - QObject *parent = 0) - : QQmlContext(parentContext, parent) - , cacheItem(cacheItem) - { - ++cacheItem->scriptRef; - } - - ~QQuickVisualDataModelContext() - { - cacheItem->Dispose(); - } - - QQuickVisualDataModelItem *cacheItem; -}; - QT_END_NAMESPACE #endif -- 2.7.4