Merge remote branch 'qt/4.8' into master-qml-staging

Conflicts:
	src/declarative/debugger/qdeclarativedebugserver.cpp
	src/plugins/qmltooling/qmltooling.pro

8 files changed, 193 insertions, 86 deletions

diff --git a/src/gui/graphicsview/qgraphicsanchorlayout_p.cpp b/src/gui/graphicsview/qgraphicsanchorlayout_p.cpp
index 48cbec3..78918cc 100644
--- a/src/gui/graphicsview/qgraphicsanchorlayout_p.cpp
+++ b/src/gui/graphicsview/qgraphicsanchorlayout_p.cpp
@@ -451,8 +451,8 @@ static QPair<QGraphicsAnchorLayoutPrivate::Interval, qreal> getFactor(qreal valu
 static qreal interpolate(const QPair<QGraphicsAnchorLayoutPrivate::Interval, qreal> &factor,
                          qreal min, qreal minPref, qreal pref, qreal maxPref, qreal max)
 {
-    qreal lower;
-    qreal upper;
+    qreal lower = 0;
+    qreal upper = 0;
 
     switch (factor.first) {
     case QGraphicsAnchorLayoutPrivate::MinimumToMinPreferred:
diff --git a/src/gui/graphicsview/qgraphicslayout.cpp b/src/gui/graphicsview/qgraphicslayout.cpp
index 904a3de..a67ae48 100644
--- a/src/gui/graphicsview/qgraphicslayout.cpp
+++ b/src/gui/graphicsview/qgraphicslayout.cpp
@@ -167,7 +167,7 @@ QGraphicsLayout::QGraphicsLayout(QGraphicsLayoutItem *parent)
                     " neither a QGraphicsWidget nor QGraphicsLayout");
         }
     }
-    setSizePolicy(QSizePolicy::Expanding, QSizePolicy::Expanding, QSizePolicy::DefaultType);
+    d_func()->sizePolicy = QSizePolicy(QSizePolicy::Expanding, QSizePolicy::Expanding, QSizePolicy::DefaultType);
     setOwnedByLayout(true);
 }
 
@@ -188,7 +188,7 @@ QGraphicsLayout::QGraphicsLayout(QGraphicsLayoutPrivate &dd, QGraphicsLayoutItem
                     " neither a QGraphicsWidget nor QGraphicsLayout");
         }
     }
-    setSizePolicy(QSizePolicy::Expanding, QSizePolicy::Expanding, QSizePolicy::DefaultType);
+    d_func()->sizePolicy = QSizePolicy(QSizePolicy::Expanding, QSizePolicy::Expanding, QSizePolicy::DefaultType);
     setOwnedByLayout(true);
 }
 
@@ -269,12 +269,20 @@ void QGraphicsLayout::activate()
         return;
     Q_ASSERT(!parentItem->isLayout());
 
-    setGeometry(parentItem->contentsRect());    // relayout children
+    if (QGraphicsLayout::instantInvalidatePropagation()) {
+        QGraphicsWidget *parentWidget = static_cast<QGraphicsWidget*>(parentItem);
+        if (!parentWidget->parentLayoutItem()) {
+            // we've reached the topmost widget, resize it
+            bool wasResized = parentWidget->testAttribute(Qt::WA_Resized);
+            parentWidget->resize(parentWidget->size());
+            parentWidget->setAttribute(Qt::WA_Resized, wasResized);
+        }
 
-    // ### bug, should be parentItem ?
-    parentLayoutItem()->updateGeometry();            // bubble up; will set activated to false
-    // ### too many resizes? maybe we should walk up the chain to the
-    // ### top-level layouted layoutItem and call activate there.
+        setGeometry(parentItem->contentsRect());    // relayout children
+    } else {
+        setGeometry(parentItem->contentsRect());    // relayout children
+        parentLayoutItem()->updateGeometry();
+    }
 }
 
 /*!
@@ -300,32 +308,36 @@ bool QGraphicsLayout::isActivated() const
 */
 void QGraphicsLayout::invalidate()
 {
-    // only mark layouts as invalid (activated = false) if we can post a LayoutRequest event.
-    QGraphicsLayoutItem *layoutItem = this;
-    while (layoutItem && layoutItem->isLayout()) {
-        // we could call updateGeometry(), but what if that method
-        // does not call the base implementation? In addition, updateGeometry()
-        // does more than we need.
-        layoutItem->d_func()->sizeHintCacheDirty = true;
-        layoutItem->d_func()->sizeHintWithConstraintCacheDirty = true;
-        layoutItem = layoutItem->parentLayoutItem();
-    }
-    if (layoutItem) {
-        layoutItem->d_func()->sizeHintCacheDirty = true;
-        layoutItem->d_func()->sizeHintWithConstraintCacheDirty = true;
-    }
-
-    bool postIt = layoutItem ? !layoutItem->isLayout() : false;
-    if (postIt) {
-        layoutItem = this;
-        while (layoutItem && layoutItem->isLayout()
-                && static_cast<QGraphicsLayout*>(layoutItem)->d_func()->activated) {
-            static_cast<QGraphicsLayout*>(layoutItem)->d_func()->activated = false;
+    if (QGraphicsLayout::instantInvalidatePropagation()) {
+        updateGeometry();
+    } else {
+        // only mark layouts as invalid (activated = false) if we can post a LayoutRequest event.
+        QGraphicsLayoutItem *layoutItem = this;
+        while (layoutItem && layoutItem->isLayout()) {
+            // we could call updateGeometry(), but what if that method
+            // does not call the base implementation? In addition, updateGeometry()
+            // does more than we need.
+            layoutItem->d_func()->sizeHintCacheDirty = true;
+            layoutItem->d_func()->sizeHintWithConstraintCacheDirty = true;
             layoutItem = layoutItem->parentLayoutItem();
         }
-        if (layoutItem && !layoutItem->isLayout()) {
-            // If a layout has a parent that is not a layout it must be a QGraphicsWidget.
-            QApplication::postEvent(static_cast<QGraphicsWidget *>(layoutItem), new QEvent(QEvent::LayoutRequest));
+        if (layoutItem) {
+            layoutItem->d_func()->sizeHintCacheDirty = true;
+            layoutItem->d_func()->sizeHintWithConstraintCacheDirty = true;
+        }
+
+        bool postIt = layoutItem ? !layoutItem->isLayout() : false;
+        if (postIt) {
+            layoutItem = this;
+            while (layoutItem && layoutItem->isLayout()
+                    && static_cast<QGraphicsLayout*>(layoutItem)->d_func()->activated) {
+                static_cast<QGraphicsLayout*>(layoutItem)->d_func()->activated = false;
+                layoutItem = layoutItem->parentLayoutItem();
+            }
+            if (layoutItem && !layoutItem->isLayout()) {
+                // If a layout has a parent that is not a layout it must be a QGraphicsWidget.
+                QApplication::postEvent(static_cast<QGraphicsWidget *>(layoutItem), new QEvent(QEvent::LayoutRequest));
+            }
         }
     }
 }
@@ -335,12 +347,27 @@ void QGraphicsLayout::invalidate()
 */
 void QGraphicsLayout::updateGeometry()
 {
-    QGraphicsLayoutItem::updateGeometry();
-    if (QGraphicsLayoutItem *parentItem = parentLayoutItem()) {
-        if (parentItem->isLayout()) {
+    Q_D(QGraphicsLayout);
+    if (QGraphicsLayout::instantInvalidatePropagation()) {
+        d->activated = false;
+        QGraphicsLayoutItem::updateGeometry();
+
+        QGraphicsLayoutItem *parentItem = parentLayoutItem();
+        if (!parentItem)
+            return;
+
+        if (parentItem->isLayout())
+            static_cast<QGraphicsLayout *>(parentItem)->invalidate();
+        else
             parentItem->updateGeometry();
-        } else {
-            invalidate();
+    } else {
+        QGraphicsLayoutItem::updateGeometry();
+        if (QGraphicsLayoutItem *parentItem = parentLayoutItem()) {
+            if (parentItem->isLayout()) {
+                parentItem->updateGeometry();
+            } else {
+                invalidate();
+            }
         }
     }
 }
@@ -446,6 +473,50 @@ void QGraphicsLayout::addChildLayoutItem(QGraphicsLayoutItem *layoutItem)
     d->addChildLayoutItem(layoutItem);
 }
 
+static bool g_instantInvalidatePropagation = false;
+
+/*!
+    \internal
+    \since 4.8
+    \see instantInvalidatePropagation
+
+    Calling this function with \a enable set to true will enable a feature that
+    makes propagation of invalidation up to ancestor layout items to be done in
+    one go. It will propagate up the parentLayoutItem() hierarchy until it has
+    reached the root. If the root item is a QGraphicsWidget, it will *post* a
+    layout request to it. When the layout request is consumed it will traverse
+    down the hierarchy of layouts and widgets and activate all layouts that is
+    invalid (not activated). This is the recommended behaviour.
+
+    If not set it will also propagate up the parentLayoutItem() hierarchy, but
+    it will stop at the \i first \i widget it encounters, and post a layout
+    request to the widget. When the layout request is consumed, this might
+    cause it to continue propagation up to the parentLayoutItem() of the
+    widget. It will continue in this fashion until it has reached a widget with
+    no parentLayoutItem(). This strategy might cause drawing artifacts, since
+    it is not done in one go, and the consumption of layout requests might be
+    interleaved by consumption of paint events, which might cause significant
+    flicker.
+    Note, this is not the recommended behavior, but for compatibility reasons
+    this is the default behaviour.
+*/
+void QGraphicsLayout::setInstantInvalidatePropagation(bool enable)
+{
+    g_instantInvalidatePropagation = enable;
+}
+
+/*!
+    \internal
+    \since 4.8
+    \see setInstantInvalidatePropagation
+
+    returns true if the complete widget/layout hierarchy is rearranged in one go.
+*/
+bool QGraphicsLayout::instantInvalidatePropagation()
+{
+    return g_instantInvalidatePropagation;
+}
+
 QT_END_NAMESPACE
 
 #endif //QT_NO_GRAPHICSVIEW
diff --git a/src/gui/graphicsview/qgraphicslayout.h b/src/gui/graphicsview/qgraphicslayout.h
index c622fb8..6031174 100644
--- a/src/gui/graphicsview/qgraphicslayout.h
+++ b/src/gui/graphicsview/qgraphicslayout.h
@@ -76,6 +76,8 @@ public:
     virtual QGraphicsLayoutItem *itemAt(int i) const = 0;
     virtual void removeAt(int index) = 0;
 
+    static void setInstantInvalidatePropagation(bool enable);
+    static bool instantInvalidatePropagation();
 protected:
     QGraphicsLayout(QGraphicsLayoutPrivate &, QGraphicsLayoutItem *);
     void addChildLayoutItem(QGraphicsLayoutItem *layoutItem);
diff --git a/src/gui/graphicsview/qgraphicslayout_p.cpp b/src/gui/graphicsview/qgraphicslayout_p.cpp
index c325602..f73fb6a 100644
--- a/src/gui/graphicsview/qgraphicslayout_p.cpp
+++ b/src/gui/graphicsview/qgraphicslayout_p.cpp
@@ -180,8 +180,13 @@ void QGraphicsLayoutPrivate::activateRecursive(QGraphicsLayoutItem *item)
 {
     if (item->isLayout()) {
         QGraphicsLayout *layout = static_cast<QGraphicsLayout *>(item);
-        if (layout->d_func()->activated)
-            layout->invalidate();
+        if (layout->d_func()->activated) {
+            if (QGraphicsLayout::instantInvalidatePropagation()) {
+                return;
+            } else {
+                layout->invalidate();   // ### LOOKS SUSPICIOUSLY WRONG!!???
+            }
+        }
 
         for (int i = layout->count() - 1; i >= 0; --i) {
             QGraphicsLayoutItem *childItem = layout->itemAt(i);
diff --git a/src/gui/graphicsview/qgraphicslinearlayout.cpp b/src/gui/graphicsview/qgraphicslinearlayout.cpp
index 5591638..40f9b1d 100644
--- a/src/gui/graphicsview/qgraphicslinearlayout.cpp
+++ b/src/gui/graphicsview/qgraphicslinearlayout.cpp
@@ -275,17 +275,13 @@ void QGraphicsLinearLayout::insertItem(int index, QGraphicsLayoutItem *item)
         qWarning("QGraphicsLinearLayout::insertItem: cannot insert itself");
         return;
     }
-    Q_ASSERT(item);
-
-    //the order of the following instructions is very important because
-    //invalidating the layout before adding the child item will make the layout happen
-    //before we try to paint the item
-    invalidate();
     d->addChildLayoutItem(item);
 
+    Q_ASSERT(item);
     d->fixIndex(&index);
     d->engine.insertRow(index, d->orientation);
     new QGridLayoutItem(&d->engine, item, d->gridRow(index), d->gridColumn(index), 1, 1, 0, index);
+    invalidate();
 }
 
 /*!
diff --git a/src/gui/graphicsview/qgraphicsscenebsptreeindex.cpp b/src/gui/graphicsview/qgraphicsscenebsptreeindex.cpp
index 92e4a55..4688fa0 100644
--- a/src/gui/graphicsview/qgraphicsscenebsptreeindex.cpp
+++ b/src/gui/graphicsview/qgraphicsscenebsptreeindex.cpp
@@ -50,14 +50,14 @@
 
     QGraphicsSceneBspTreeIndex index use a BSP(Binary Space Partitioning)
     implementation to discover items quickly. This implementation is
-    very efficient for static scene. It has a depth that you can set.
+    very efficient for static scenes. It has a depth that you can set.
     The depth directly affects performance and memory usage; the latter
     growing exponentially with the depth of the tree. With an optimal tree
     depth, the index can instantly determine the locality of items, even
     for scenes with thousands or millions of items. This also greatly improves
     rendering performance.
 
-    By default, the value is 0, in which case Qt will guess a reasonable
+    By default, the depth value is 0, in which case Qt will guess a reasonable
     default depth based on the size, location and number of items in the
     scene. If these parameters change frequently, however, you may experience
     slowdowns as the index retunes the depth internally. You can avoid
diff --git a/src/gui/graphicsview/qgraphicswidget.cpp b/src/gui/graphicsview/qgraphicswidget.cpp
index 675a5c5..141e305 100644
--- a/src/gui/graphicsview/qgraphicswidget.cpp
+++ b/src/gui/graphicsview/qgraphicswidget.cpp
@@ -354,8 +354,10 @@ void QGraphicsWidget::setGeometry(const QRectF &rect)
         newGeom = rect;
         newGeom.setSize(rect.size().expandedTo(effectiveSizeHint(Qt::MinimumSize))
                                    .boundedTo(effectiveSizeHint(Qt::MaximumSize)));
-        if (newGeom == d->geom)
-            return;
+
+        if (newGeom == d->geom) {
+            goto relayoutChildrenAndReturn;
+        }
 
         // setPos triggers ItemPositionChange, which can adjust position
         wd->inSetGeometry = 1;
@@ -363,8 +365,9 @@ void QGraphicsWidget::setGeometry(const QRectF &rect)
         wd->inSetGeometry = 0;
         newGeom.moveTopLeft(pos());
 
-        if (newGeom == d->geom)
-           return;
+        if (newGeom == d->geom) {
+            goto relayoutChildrenAndReturn;
+        }
 
          // Update and prepare to change the geometry (remove from index) if the size has changed.
         if (wd->scene) {
@@ -375,35 +378,54 @@ void QGraphicsWidget::setGeometry(const QRectF &rect)
     }
 
     // Update the layout item geometry
-    bool moved = oldPos != pos();
-    if (moved) {
-        // Send move event.
-        QGraphicsSceneMoveEvent event;
-        event.setOldPos(oldPos);
-        event.setNewPos(pos());
-        QApplication::sendEvent(this, &event);
-        if (wd->inSetPos) {
-            //set the new pos
-            d->geom.moveTopLeft(pos());
-            emit geometryChanged();
-            return;
+    {
+        bool moved = oldPos != pos();
+        if (moved) {
+            // Send move event.
+            QGraphicsSceneMoveEvent event;
+            event.setOldPos(oldPos);
+            event.setNewPos(pos());
+            QApplication::sendEvent(this, &event);
+            if (wd->inSetPos) {
+                //set the new pos
+                d->geom.moveTopLeft(pos());
+                emit geometryChanged();
+                goto relayoutChildrenAndReturn;
+            }
+        }
+        QSizeF oldSize = size();
+        QGraphicsLayoutItem::setGeometry(newGeom);
+        // Send resize event
+        bool resized = newGeom.size() != oldSize;
+        if (resized) {
+            QGraphicsSceneResizeEvent re;
+            re.setOldSize(oldSize);
+            re.setNewSize(newGeom.size());
+            if (oldSize.width() != newGeom.size().width())
+                emit widthChanged();
+            if (oldSize.height() != newGeom.size().height())
+                emit heightChanged();
+            QGraphicsLayout *lay = wd->layout;
+            if (QGraphicsLayout::instantInvalidatePropagation()) {
+                if (!lay || lay->isActivated()) {
+                    QApplication::sendEvent(this, &re);
+                }
+            } else {
+                QApplication::sendEvent(this, &re);
+            }
         }
     }
-    QSizeF oldSize = size();
-    QGraphicsLayoutItem::setGeometry(newGeom);
-    // Send resize event
-    bool resized = newGeom.size() != oldSize;
-    if (resized) {
-        QGraphicsSceneResizeEvent re;
-        re.setOldSize(oldSize);
-        re.setNewSize(newGeom.size());
-        if (oldSize.width() != newGeom.size().width())
-            emit widthChanged();
-        if (oldSize.height() != newGeom.size().height())
-            emit heightChanged();
-        QApplication::sendEvent(this, &re);
-    }
+
     emit geometryChanged();
+relayoutChildrenAndReturn:
+    if (QGraphicsLayout::instantInvalidatePropagation()) {
+        if (QGraphicsLayout *lay = wd->layout) {
+            if (!lay->isActivated()) {
+                QEvent layoutRequest(QEvent::LayoutRequest);
+                QApplication::sendEvent(this, &layoutRequest);
+            }
+        }
+    }
 }
 
 /*!
@@ -1052,16 +1074,31 @@ void QGraphicsWidget::updateGeometry()
     QGraphicsLayoutItem *parentItem = parentLayoutItem();
 
     if (parentItem && parentItem->isLayout()) {
-        parentItem->updateGeometry();
+        if (QGraphicsLayout::instantInvalidatePropagation()) {
+            static_cast<QGraphicsLayout *>(parentItem)->invalidate();
+        } else {
+            parentItem->updateGeometry();
+        }
     } else {
         if (parentItem) {
+            // This is for custom layouting
             QGraphicsWidget *parentWid = parentWidget();    //###
             if (parentWid->isVisible())
                 QApplication::postEvent(parentWid, new QEvent(QEvent::LayoutRequest));
+        } else {
+            /**
+             * If this is the topmost widget, post a LayoutRequest event to the widget.
+             * When the event is received, it will start flowing all the way down to the leaf
+             * widgets in one go. This will make a relayout flicker-free.
+             */
+            if (QGraphicsLayout::instantInvalidatePropagation())
+                QApplication::postEvent(static_cast<QGraphicsWidget *>(this), new QEvent(QEvent::LayoutRequest));
+        }
+        if (!QGraphicsLayout::instantInvalidatePropagation()) {
+            bool wasResized = testAttribute(Qt::WA_Resized);
+            resize(size()); // this will restrict the size
+            setAttribute(Qt::WA_Resized, wasResized);
         }
-        bool wasResized = testAttribute(Qt::WA_Resized);
-        resize(size()); // this will restrict the size
-        setAttribute(Qt::WA_Resized, wasResized);
     }
 }
 
diff --git a/src/gui/graphicsview/qgraphicswidget_p.cpp b/src/gui/graphicsview/qgraphicswidget_p.cpp
index 4580055..63d7298 100644
--- a/src/gui/graphicsview/qgraphicswidget_p.cpp
+++ b/src/gui/graphicsview/qgraphicswidget_p.cpp
@@ -857,8 +857,6 @@ void QGraphicsWidgetPrivate::setWidth(qreal w)
     if (q->geometry().width() == w)
         return;
 
-    QRectF oldGeom = q->geometry();
-
     q->setGeometry(QRectF(q->x(), q->y(), w, height()));
 }
 
@@ -882,8 +880,6 @@ void QGraphicsWidgetPrivate::setHeight(qreal h)
     if (q->geometry().height() == h)
         return;
 
-    QRectF oldGeom = q->geometry();
-
     q->setGeometry(QRectF(q->x(), q->y(), width(), h));
 }