Incubators are not async with the threaded renderer.

The threaded incubator relies on the event loop spinning to signal
item updates.  This change ensures that the event loop is processed
while items are being created and that the render loop is woken
if it is sleeping.

Also cancel delegate incubation correctly during destruction.

Change-Id: Ib5bb55c788411490e0959c75933da587fdfd4b8c
Reviewed-by: Yunqiao Yin <charles.yin@nokia.com>
Reviewed-by: Michael Brasser <michael.brasser@nokia.com>

7 files changed, 50 insertions, 11 deletions

diff --git a/src/quick/items/qquickcanvas.cpp b/src/quick/items/qquickcanvas.cpp
index 6b0eb5b96b..e6a3e87401 100644
--- a/src/quick/items/qquickcanvas.cpp
+++ b/src/quick/items/qquickcanvas.cpp
@@ -94,11 +94,10 @@ protected:
     {
         if (e->type() == QEvent::User) {
             Q_ASSERT(m_eventSent);
-
-            bool *amtp = m_canvas->windowManager->allowMainThreadProcessing();
+            volatile bool *amtp = m_canvas->windowManager->allowMainThreadProcessing();
             while (incubatingObjectCount()) {
                 if (amtp)
-                    incubateWhile(amtp);
+                    incubateWhile(amtp, 2);
                 else
                     incubateFor(5);
                 QCoreApplication::processEvents();
@@ -115,6 +114,8 @@ protected:
             m_eventSent = true;
             QCoreApplication::postEvent(this, new QEvent(QEvent::User));
         }
+        // If no animations are running, the renderer may be waiting
+        m_canvas->windowManager->wakeup();
     }
 
 private:
diff --git a/src/quick/items/qquickitemview.cpp b/src/quick/items/qquickitemview.cpp
index f62fa94f5e..d5ce567590 100644
--- a/src/quick/items/qquickitemview.cpp
+++ b/src/quick/items/qquickitemview.cpp
@@ -2162,6 +2162,12 @@ void QQuickItemViewPrivate::clear()
     createHighlight();
     trackedItem = 0;
 
+    if (requestedIndex >= 0 && requestedAsync) {
+        if (model)
+            model->cancel(requestedIndex);
+        requestedIndex = -1;
+    }
+
     markExtentsDirty();
     itemCount = 0;
 }
diff --git a/src/quick/items/qquickvisualdatamodel.cpp b/src/quick/items/qquickvisualdatamodel.cpp
index 4fdcc98602..0bdf0cb5af 100644
--- a/src/quick/items/qquickvisualdatamodel.cpp
+++ b/src/quick/items/qquickvisualdatamodel.cpp
@@ -450,6 +450,21 @@ QQuickVisualDataModel::ReleaseFlags QQuickVisualDataModel::release(QQuickItem *i
     return stat;
 }
 
+// Cancel a requested async item
+void QQuickVisualDataModel::cancel(int index)
+{
+    Q_D(QQuickVisualDataModel);
+    if (!d->m_delegate || index < 0 || index >= d->m_compositor.count(d->m_compositorGroup)) {
+        qWarning() << "VisualDataModel::cancel: index out range" << index << d->m_compositor.count(d->m_compositorGroup);
+        return;
+    }
+
+    Compositor::iterator it = d->m_compositor.find(d->m_compositorGroup, index);
+    QQuickVisualDataModelItem *cacheItem = it->inCache() ? d->m_cache.at(it.cacheIndex) : 0;
+    if (cacheItem && cacheItem->incubationTask)
+        d->releaseIncubator(cacheItem->incubationTask);
+}
+
 void QQuickVisualDataModelPrivate::group_append(
         QDeclarativeListProperty<QQuickVisualDataGroup> *property, QQuickVisualDataGroup *group)
 {
@@ -708,8 +723,10 @@ void QQuickVisualDataModelPrivate::incubatorStatusChanged(QVDMIncubationTask *in
         incubationTask->incubatingContext = 0;
         if (!cacheItem->isReferenced()) {
             int cidx = m_cache.indexOf(cacheItem);
-            m_compositor.clearFlags(Compositor::Cache, cidx, 1, Compositor::CacheFlag);
-            m_cache.removeAt(cidx);
+            if (cidx >= 0) {
+                m_compositor.clearFlags(Compositor::Cache, cidx, 1, Compositor::CacheFlag);
+                m_cache.removeAt(cidx);
+            }
             delete cacheItem;
             Q_ASSERT(m_cache.count() == m_compositor.count(Compositor::Cache));
         }
diff --git a/src/quick/items/qquickvisualdatamodel_p.h b/src/quick/items/qquickvisualdatamodel_p.h
index 54cc16d660..043fcfd8a9 100644
--- a/src/quick/items/qquickvisualdatamodel_p.h
+++ b/src/quick/items/qquickvisualdatamodel_p.h
@@ -106,6 +106,7 @@ public:
     bool isValid() const { return delegate() != 0; }
     QQuickItem *item(int index, bool asynchronous=false);
     ReleaseFlags release(QQuickItem *item);
+    void cancel(int index);
     virtual QString stringValue(int index, const QString &role);
     virtual void setWatchedRoles(QList<QByteArray> roles);
 
diff --git a/src/quick/items/qquickvisualitemmodel_p.h b/src/quick/items/qquickvisualitemmodel_p.h
index f1c9d066be..7d2b79f718 100644
--- a/src/quick/items/qquickvisualitemmodel_p.h
+++ b/src/quick/items/qquickvisualitemmodel_p.h
@@ -69,6 +69,7 @@ public:
     virtual bool isValid() const = 0;
     virtual QQuickItem *item(int index, bool asynchronous=false) = 0;
     virtual ReleaseFlags release(QQuickItem *item) = 0;
+    virtual void cancel(int) {}
     virtual QString stringValue(int, const QString &) = 0;
     virtual void setWatchedRoles(QList<QByteArray> roles) = 0;
 
diff --git a/src/quick/items/qquickwindowmanager.cpp b/src/quick/items/qquickwindowmanager.cpp
index 16b6d92e22..79fd266e1e 100644
--- a/src/quick/items/qquickwindowmanager.cpp
+++ b/src/quick/items/qquickwindowmanager.cpp
@@ -193,6 +193,7 @@ public:
     void resize(QQuickCanvas *canvas, const QSize &size);
     void handleDeferredUpdate();
     void maybeUpdate(QQuickCanvas *canvas);
+    void wakeup();
 
     void startRendering();
     void stopRendering();
@@ -202,7 +203,7 @@ public:
 
     void initialize();
 
-    bool *allowMainThreadProcessing() { return &allowMainThreadProcessingFlag; }
+    volatile bool *allowMainThreadProcessing() { return &allowMainThreadProcessingFlag; }
 
     bool event(QEvent *);
 
@@ -243,7 +244,7 @@ private:
     QMutex mutex;
     QWaitCondition condition;
 
-    bool allowMainThreadProcessingFlag;
+    volatile bool allowMainThreadProcessingFlag;
 
     int isGuiLocked;
     uint animationRunning: 1;
@@ -299,12 +300,13 @@ public:
     void paint(QQuickCanvas *canvas);
     QImage grab(QQuickCanvas *canvas);
     void resize(QQuickCanvas *canvas, const QSize &size);
+    void wakeup();
 
     void maybeUpdate(QQuickCanvas *canvas);
 
     void releaseResources() { }
 
-    bool *allowMainThreadProcessing();
+    volatile bool *allowMainThreadProcessing();
 
     QSGContext *sceneGraphContext() const;
 
@@ -1129,6 +1131,14 @@ void QQuickRenderThreadSingleContextWindowManager::maybeUpdate(QQuickCanvas *)
 
 }
 
+void QQuickRenderThreadSingleContextWindowManager::wakeup()
+{
+    lockInGui();
+    if (isRenderBlocked)
+        wake();
+    unlockInGui();
+}
+
 QQuickTrivialWindowManager::QQuickTrivialWindowManager()
     : gl(0)
     , eventPending(false)
@@ -1268,9 +1278,11 @@ void QQuickTrivialWindowManager::maybeUpdate(QQuickCanvas *canvas)
     }
 }
 
+void QQuickTrivialWindowManager::wakeup()
+{
+}
 
-
-bool *QQuickTrivialWindowManager::allowMainThreadProcessing()
+volatile bool *QQuickTrivialWindowManager::allowMainThreadProcessing()
 {
     return 0;
 }
diff --git a/src/quick/items/qquickwindowmanager_p.h b/src/quick/items/qquickwindowmanager_p.h
index 86312655b3..a0bdf08a91 100644
--- a/src/quick/items/qquickwindowmanager_p.h
+++ b/src/quick/items/qquickwindowmanager_p.h
@@ -64,8 +64,9 @@ public:
     virtual void resize(QQuickCanvas *canvas, const QSize &size) = 0;
 
     virtual void maybeUpdate(QQuickCanvas *canvas) = 0;
+    virtual void wakeup() = 0;
 
-    virtual bool *allowMainThreadProcessing() = 0;
+    virtual volatile bool *allowMainThreadProcessing() = 0;
 
     virtual QSGContext *sceneGraphContext() const = 0;