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/****************************************************************************
**
** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
** All rights reserved.
** Contact: Nokia Corporation (qt-info@nokia.com)
**
** This file is part of the QtDeclarative module of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:LGPL$
** No Commercial Usage
** This file contains pre-release code and may not be distributed.
** You may use this file in accordance with the terms and conditions
** contained in the Technology Preview License Agreement accompanying
** this package.
**
** GNU Lesser General Public License Usage
** Alternatively, this file may be used under the terms of the GNU Lesser
** General Public License version 2.1 as published by the Free Software
** Foundation and appearing in the file LICENSE.LGPL included in the
** packaging of this file. Please review the following information to
** ensure the GNU Lesser General Public License version 2.1 requirements
** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
**
** In addition, as a special exception, Nokia gives you certain additional
** rights. These rights are described in the Nokia Qt LGPL Exception
** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
**
** If you have questions regarding the use of this file, please contact
** Nokia at qt-info@nokia.com.
**
**
**
**
**
**
**
**
** $QT_END_LICENSE$
**
****************************************************************************/
#include <QDebug>
#include <QCoreApplication>
#include "qml.h"
#include "qmlstate_p.h"
#include "qmlstategroup_p.h"
#include "qmlstateoperations_p.h"
#include "qfxperf_p_p.h"
#include "qmlgraphicspositioners_p.h"
#include "qmlgraphicspositioners_p_p.h"
QT_BEGIN_NAMESPACE
void QmlGraphicsBasePositionerPrivate::watchChanges(QmlGraphicsItem *other)
{
Q_Q(QmlGraphicsBasePositioner);
QObject::connect(other, SIGNAL(visibleChanged()),
q, SLOT(prePositioning()));
QObject::connect(other, SIGNAL(opacityChanged()),
q, SLOT(prePositioning()));
QObject::connect(other, SIGNAL(heightChanged()),
q, SLOT(prePositioning()));
QObject::connect(other, SIGNAL(widthChanged()),
q, SLOT(prePositioning()));
static_cast<QmlGraphicsItemPrivate*>(QGraphicsItemPrivate::get(other))->registerSiblingOrderNotification(this);
watched << other;
}
void QmlGraphicsBasePositionerPrivate::unwatchChanges(QmlGraphicsItem* other)
{
Q_Q(QmlGraphicsBasePositioner);
bool stillAlive = false; //Use the return from disconnect to see if it was deleted or just reparented
stillAlive |= QObject::disconnect(other, SIGNAL(visibleChanged()),
q, SLOT(prePositioning()));
stillAlive |= QObject::disconnect(other, SIGNAL(opacityChanged()),
q, SLOT(prePositioning()));
stillAlive |= QObject::disconnect(other, SIGNAL(heightChanged()),
q, SLOT(prePositioning()));
stillAlive |= QObject::disconnect(other, SIGNAL(widthChanged()),
q, SLOT(prePositioning()));
if(stillAlive)
static_cast<QmlGraphicsItemPrivate*>(QGraphicsItemPrivate::get(other))
->unregisterSiblingOrderNotification(this);
watched.removeAll(other);
}
/*!
\internal
\class QmlGraphicsBasePositioner
\ingroup group_layouts
\brief The QmlGraphicsBasePositioner class provides a base for QmlGraphics layouts.
To create a QmlGraphics Positioner, simply subclass QmlGraphicsBasePositioner and implement
doLayout(), which is automatically called when the layout might need
updating.
It is strongly recommended that in your implementation of doLayout()
that you use the move, remove and add transitions when those conditions
arise. You can use the applyAdd, applyMove and applyRemove functions
to do this easily.
Note also that the subclass is responsible for adding the
spacing in between items.
*/
QmlGraphicsBasePositioner::QmlGraphicsBasePositioner(AutoUpdateType at, QmlGraphicsItem *parent)
: QmlGraphicsItem(*(new QmlGraphicsBasePositionerPrivate), parent)
{
Q_D(QmlGraphicsBasePositioner);
d->init(at);
}
QmlGraphicsBasePositioner::QmlGraphicsBasePositioner(QmlGraphicsBasePositionerPrivate &dd, AutoUpdateType at, QmlGraphicsItem *parent)
: QmlGraphicsItem(dd, parent)
{
Q_D(QmlGraphicsBasePositioner);
d->init(at);
}
int QmlGraphicsBasePositioner::spacing() const
{
Q_D(const QmlGraphicsBasePositioner);
return d->_spacing;
}
void QmlGraphicsBasePositioner::setSpacing(int s)
{
Q_D(QmlGraphicsBasePositioner);
if (s==d->_spacing)
return;
d->_spacing = s;
prePositioning();
emit spacingChanged();
}
QmlTransition *QmlGraphicsBasePositioner::move() const
{
Q_D(const QmlGraphicsBasePositioner);
return d->moveTransition;
}
void QmlGraphicsBasePositioner::setMove(QmlTransition *mt)
{
Q_D(QmlGraphicsBasePositioner);
d->moveTransition = mt;
}
QmlTransition *QmlGraphicsBasePositioner::add() const
{
Q_D(const QmlGraphicsBasePositioner);
return d->addTransition;
}
void QmlGraphicsBasePositioner::setAdd(QmlTransition *add)
{
Q_D(QmlGraphicsBasePositioner);
d->addTransition = add;
}
QmlTransition *QmlGraphicsBasePositioner::remove() const
{
Q_D(const QmlGraphicsBasePositioner);
return d->removeTransition;
}
void QmlGraphicsBasePositioner::setRemove(QmlTransition *remove)
{
Q_D(QmlGraphicsBasePositioner);
d->removeTransition = remove;
}
void QmlGraphicsBasePositioner::componentComplete()
{
QmlGraphicsItem::componentComplete();
#ifdef Q_ENABLE_PERFORMANCE_LOG
QmlPerfTimer<QmlPerf::BasepositionerComponentComplete> cc;
#endif
prePositioning();
}
QVariant QmlGraphicsBasePositioner::itemChange(GraphicsItemChange change,
const QVariant &value)
{
if (change == ItemChildAddedChange ||
change == ItemChildRemovedChange) {
prePositioning();
}
return QmlGraphicsItem::itemChange(change, value);
}
bool QmlGraphicsBasePositioner::event(QEvent *e)
{
Q_D(QmlGraphicsBasePositioner);
if (e->type() == QEvent::User) {
d->_ep = false;
d->_stableItems += d->_newItems;
d->_leavingItems.clear();
d->_newItems.clear();
return true;
}
return QmlGraphicsItem::event(e);
}
/*!
Items that have just been added to the positioner. This includes invisible items
that have turned visible.
*/
QSet<QmlGraphicsItem *>* QmlGraphicsBasePositioner::newItems()
{
Q_D(QmlGraphicsBasePositioner);
return &d->_newItems;
}
/*!
Items that are visible in the positioner, not including ones that have just been added.
*/
QSet<QmlGraphicsItem *>* QmlGraphicsBasePositioner::items()
{
Q_D(QmlGraphicsBasePositioner);
return &d->_stableItems;
}
/*!
Items that have just left the positioner. This includes visible items
that have turned invisible.
*/
QSet<QmlGraphicsItem *>* QmlGraphicsBasePositioner::leavingItems()
{
Q_D(QmlGraphicsBasePositioner);
return &d->_leavingItems;
}
void QmlGraphicsBasePositioner::prePositioning()
{
Q_D(QmlGraphicsBasePositioner);
if (!isComponentComplete() || d->_movingItem)
return;
d->queuedPositioning = false;
if (!d->_ep) {
d->_ep = true;
QCoreApplication::postEvent(this, new QEvent(QEvent::User));
}
QSet<QmlGraphicsItem *> allItems;
//Need to order children by creation order modified by stacking order
//###can we avoid using the QGraphicsItemPrivate?
QList<QGraphicsItem *> children = childItems();
qSort(children.begin(), children.end(), d->insertionOrder);
positionedItems = QList<QmlGraphicsItem*>();
for (int ii = 0; ii < children.count(); ++ii) {
QmlGraphicsItem *child = qobject_cast<QmlGraphicsItem *>(children.at(ii));
if (!child)
continue;
if (!d->_items.contains(child)){
d->watchChanges(child);
d->_items += child;
}
if (child->opacity() == 0.0){
if (d->_stableItems.contains(child)){
d->_leavingItems += child;
d->_stableItems -= child;
}
}else if (!d->_stableItems.contains(child)){
d->_newItems+=child;
}
allItems += child;
positionedItems << child;
}
QSet<QmlGraphicsItem *> deletedItems = d->_items - allItems;
foreach(QmlGraphicsItem *child, deletedItems){
d->unwatchChanges(child);
d->_items -= child;
}
d->_animated.clear();
doPositioning();
finishApplyTransitions();
//Set implicit size to the size of its children
//###To keep this valid, do we need to update on pos change as well?
qreal h = 0.0f;
qreal w = 0.0f;
foreach(QmlGraphicsItem *child, d->_items){
if(!child->isVisible() || child->opacity() <= 0)
continue;
h = qMax(h, child->y() + child->height());
w = qMax(w, child->x() + child->width());
}
setImplicitHeight(h);
setImplicitWidth(w);
}
void QmlGraphicsBasePositioner::applyTransition(const QList<QPair<QString, QVariant> >& changes, QmlGraphicsItem* target, QmlStateOperation::ActionList &actions)
{
Q_D(QmlGraphicsBasePositioner);
if (!target)
return;
for (int ii=0; ii<changes.size(); ++ii){
QVariant val = changes[ii].second;
actions << Action(target, changes[ii].first, val);
}
d->_animated << target;
}
void QmlGraphicsBasePositioner::finishApplyTransitions()
{
Q_D(QmlGraphicsBasePositioner);
// Note that if a transition is not set the transition manager will
// apply the changes directly, in the case someone uses applyAdd/Move/Remove
// without testing add()/move()/remove().
d->addTransitionManager.transition(d->addActions, d->addTransition);
d->moveTransitionManager.transition(d->moveActions, d->moveTransition);
d->removeTransitionManager.transition(d->removeActions, d->removeTransition);
d->addActions.clear();
d->moveActions.clear();
d->removeActions.clear();
}
void QmlGraphicsBasePositioner::setMovingItem(QmlGraphicsItem *i)
{
Q_D(QmlGraphicsBasePositioner);
d->_movingItem = i;
}
/*!
Applies the positioner's add transition to the \a target item.\a changes is a list of property,value
pairs which will be changed on the target using the add transition.
*/
void QmlGraphicsBasePositioner::applyAdd(const QList<QPair<QString, QVariant> >& changes, QmlGraphicsItem* target)
{
Q_D(QmlGraphicsBasePositioner);
applyTransition(changes,target, d->addActions);
}
/*!
Applies the positioner's move transition to the \a target.\a changes is a list of property,value pairs
which will be changed on the target using the move transition.
*/
void QmlGraphicsBasePositioner::applyMove(const QList<QPair<QString, QVariant> >& changes, QmlGraphicsItem* target)
{
Q_D(QmlGraphicsBasePositioner);
applyTransition(changes,target, d->moveActions);
}
/*!
Applies the positioner's remove transition to the \a target item.\a changes is a list of
property,value pairs which will be changed on the target using the remove transition.
*/
void QmlGraphicsBasePositioner::applyRemove(const QList<QPair<QString, QVariant> >& changes, QmlGraphicsItem* target)
{
Q_D(QmlGraphicsBasePositioner);
applyTransition(changes,target, d->removeActions);
}
QML_DEFINE_TYPE(Qt,4,6,Column,QmlGraphicsColumn)
/*!
\qmlclass Column QmlGraphicsColumn
\brief The Column item lines up its children vertically.
\inherits Item
The Column item positions its child items so that they are vertically
aligned and not overlapping. Spacing between items can be added.
The below example positions differently shaped rectangles using a Column.
\table
\row
\o \image verticalpositioner_example.png
\o
\qml
Column {
spacing: 2
Rectangle { color: "red"; width: 50; height: 50 }
Rectangle { color: "green"; width: 20; height: 50 }
Rectangle { color: "blue"; width: 50; height: 20 }
}
\endqml
\endtable
Column also provides for transitions to be set when items are added, moved,
or removed in the positioner. Adding and removing apply both to items which are deleted
or have their position in the document changed so as to no longer be children of the positioner,
as well as to items which have their opacity set to or from zero so as to appear or disappear.
\table
\row
\o \image verticalpositioner_transition.gif
\o
\qml
Column {
spacing: 2
remove: ...
add: ...
move: ...
...
}
\endqml
\endtable
Note that the positioner assumes that the x and y positions of its children
will not change. If you manually change the x or y properties in script, bind
the x or y properties, or use anchors on a child of a positioner, then the
positioner may exhibit strange behaviour.
*/
/*!
\qmlproperty Transition Column::remove
This property holds the transition to apply when removing an item from the positioner. The transition is only applied to the removed items.
Positioner transitions will only affect the position (x,y) of items.
Removed can mean that either the object has been deleted or reparented, and thus is now longer a child of the positioner, or that the object has had its opacity set to zero, and thus is no longer visible.
*/
/*!
\qmlproperty Transition Column::add
This property holds the transition to be applied when adding an item to the positioner. The transition will only be applied to the added item(s).
Positioner transitions will only affect the position (x,y) of items.
Added can mean that either the object has been created or reparented, and thus is now a child or the positioner, or that the object has had its opacity increased from zero, and thus is now visible.
*/
/*!
\qmlproperty Transition Column::move
This property holds the transition to apply when moving an item within the positioner.
Positioner transitions will only affect the position (x,y) of items.
This can happen when other items are added or removed from the positioner, or when items resize themselves.
\table
\row
\o \image positioner-move.gif
\o
\qml
Column {
move: Transition {
NumberAnimation {
matchProperties: "y"
ease: "easeOutBounce"
}
}
}
\endqml
\endtable
*/
/*!
\qmlproperty int Column::spacing
spacing is the amount in pixels left empty between each adjacent
item, and defaults to 0.
The below example places a Grid containing a red, a blue and a
green rectangle on a gray background. The area the grid positioner
occupies is colored white. The top positioner has the default of no spacing,
and the bottom positioner has its spacing set to 2.
\image spacing_a.png
\image spacing_b.png
*/
/*!
\internal
\class QmlGraphicsColumn
\brief The QmlGraphicsColumn class lines up items vertically.
\ingroup group_positioners
*/
QmlGraphicsColumn::QmlGraphicsColumn(QmlGraphicsItem *parent)
: QmlGraphicsBasePositioner(Vertical, parent)
{
}
inline bool isInvisible(QmlGraphicsItem *child)
{
return child->opacity() == 0.0 || !child->isVisible() || !child->width() || !child->height();
}
void QmlGraphicsColumn::doPositioning()
{
int voffset = 0;
foreach(QmlGraphicsItem* item, *leavingItems()){
if (remove()){
QList<QPair<QString,QVariant> > changes;
applyRemove(changes, item);
}
}
QList<QmlGraphicsItem *> children = positionedItems;
for (int ii = 0; ii < children.count(); ++ii) {
QmlGraphicsItem *child = children.at(ii);
if (!child || isInvisible(child))
continue;
bool needMove = (child->y() != voffset || child->x());
QList<QPair<QString, QVariant> > changes;
changes << qMakePair(QString(QLatin1String("y")),QVariant(voffset));
changes << qMakePair(QString(QLatin1String("x")),QVariant(0));
if (needMove && items()->contains(child) && move()) {
applyMove(changes,child);
} else if (!items()->contains(child) && add()) {
applyAdd(changes,child);
} else if (needMove) {
setMovingItem(child);
child->setY(voffset);
setMovingItem(0);
}
voffset += child->height();
voffset += spacing();
}
}
QML_DEFINE_TYPE(Qt,4,6,Row,QmlGraphicsRow)
/*!
\qmlclass Row QmlGraphicsRow
\brief The Row item lines up its children horizontally.
\inherits Item
The Row item positions its child items so that they are
horizontally aligned and not overlapping. Spacing can be added between the
items, and a margin around all items can also be added. It also provides for
transitions to be set when items are added, moved, or removed in the
positioner. Adding and removing apply both to items which are deleted or have
their position in the document changed so as to no longer be children of the
positioner, as well as to items which have their opacity set to or from zero
so as to appear or disappear.
The below example lays out differently shaped rectangles using a Row.
\qml
Row {
spacing: 2
Rectangle { color: "red"; width: 50; height: 50 }
Rectangle { color: "green"; width: 20; height: 50 }
Rectangle { color: "blue"; width: 50; height: 20 }
}
\endqml
\image horizontalpositioner_example.png
Note that the positioner assumes that the x and y positions of its children
will not change. If you manually change the x or y properties in script, bind
the x or y properties, or use anchors on a child of a positioner, then the
positioner may exhibit strange behaviour.
*/
/*!
\qmlproperty Transition Row::remove
This property holds the transition to apply when removing an item from the positioner.
The transition will only be applied to the removed item(s).
Positioner transitions will only affect the position (x,y) of items.
Removed can mean that either the object has been deleted or reparented, and thus is now longer a child of the positioner, or that the object has had its opacity set to zero, and thus is no longer visible.
Note that if the item counts as removed because its opacity is zero it will not be visible during the transition unless you set the opacity in the transition, like in the below example.
*/
/*!
\qmlproperty Transition Row::add
This property holds the transition to apply when adding an item to the positioner.
The transition will only be applied to the added item(s).
Positioner transitions will only affect the position (x,y) of items.
Added can mean that either the object has been created or reparented, and thus is now a child or the positioner, or that the object has had its opacity increased from zero, and thus is now visible.
*/
/*!
\qmlproperty Transition Row::move
This property holds the transition to apply when moving an item within the positioner.
Positioner transitions will only affect the position (x,y) of items.
This can happen when other items are added or removed from the positioner, or when items resize themselves.
\qml
Row {
id: positioner
move: Transition {
NumberAnimation {
matchProperties: "x"
ease: "easeOutBounce"
}
}
}
\endqml
*/
/*!
\qmlproperty int Row::spacing
spacing is the amount in pixels left empty between each adjacent
item, and defaults to 0.
The below example places a Grid containing a red, a blue and a
green rectangle on a gray background. The area the grid positioner
occupies is colored white. The top positioner has the default of no spacing,
and the bottom positioner has its spacing set to 2.
\image spacing_a.png
\image spacing_b.png
*/
/*!
\internal
\class QmlGraphicsRow
\brief The QmlGraphicsRow class lines up items horizontally.
\ingroup group_positioners
*/
QmlGraphicsRow::QmlGraphicsRow(QmlGraphicsItem *parent)
: QmlGraphicsBasePositioner(Horizontal, parent)
{
}
void QmlGraphicsRow::doPositioning()
{
int hoffset = 0;
foreach(QmlGraphicsItem* item, *leavingItems()){
if (remove()){
QList<QPair<QString,QVariant> > changes;
applyRemove(changes, item);
}
}
QList<QmlGraphicsItem *> children = positionedItems;
for (int ii = 0; ii < children.count(); ++ii) {
QmlGraphicsItem *child = children.at(ii);
if (!child || isInvisible(child))
continue;
bool needMove = (child->x() != hoffset || child->y());
QList<QPair<QString, QVariant> > changes;
changes << qMakePair(QString(QLatin1String("x")),QVariant(hoffset));
changes << qMakePair(QString(QLatin1String("y")),QVariant(0));
if (needMove && items()->contains(child) && move()) {
applyMove(changes,child);
} else if (!items()->contains(child) && add()) {
applyAdd(changes,child);
} else if (needMove) {
setMovingItem(child);
child->setX(hoffset);
setMovingItem(0);
}
hoffset += child->width();
hoffset += spacing();
}
}
QML_DEFINE_TYPE(Qt,4,6,Grid,QmlGraphicsGrid)
/*!
\qmlclass Grid QmlGraphicsGrid
\brief The Grid item positions its children in a grid.
\inherits Item
The Grid item positions its child items so that they are
aligned in a grid and are not overlapping. Spacing can be added
between the items. It also provides for transitions to be set when items are
added, moved, or removed in the positioner. Adding and removing apply
both to items which are deleted or have their position in the
document changed so as to no longer be children of the positioner, as
well as to items which have their opacity set to or from zero so
as to appear or disappear.
The Grid defaults to using four columns, and as many rows as
are necessary to fit all the child items. The number of rows
and/or the number of columns can be constrained by setting the rows
or columns properties. The grid positioner calculates a grid with
rectangular cells of sufficient size to hold all items, and then
places the items in the cells, going across then down, and
positioning each item at the (0,0) corner of the cell. The below
example demonstrates this.
\table
\row
\o \image gridLayout_example.png
\o
\qml
Grid {
columns: 3
spacing: 2
Rectangle { color: "red"; width: 50; height: 50 }
Rectangle { color: "green"; width: 20; height: 50 }
Rectangle { color: "blue"; width: 50; height: 20 }
Rectangle { color: "cyan"; width: 50; height: 50 }
Rectangle { color: "magenta"; width: 10; height: 10 }
}
\endqml
\endtable
Note that the positioner assumes that the x and y positions of its children
will not change. If you manually change the x or y properties in script, bind
the x or y properties, or use anchors on a child of a positioner, then the
positioner may exhibit strange behaviour.
*/
/*!
\qmlproperty Transition Grid::remove
This property holds the transition to apply when removing an item from the positioner.
The transition is only applied to the removed item(s).
Positioner transitions will only affect the position (x,y) of items.
Removed can mean that either the object has been deleted or
reparented, and thus is now longer a child of the positioner, or that
the object has had its opacity set to zero, and thus is no longer
visible.
*/
/*!
\qmlproperty Transition Grid::add
This property holds the transition to apply when adding an item to the positioner.
The transition is only applied to the added item(s).
Positioner transitions will only affect the position (x,y) of items.
Added can mean that either the object has been created or
reparented, and thus is now a child or the positioner, or that the
object has had its opacity increased from zero, and thus is now
visible.
*/
/*!
\qmlproperty Transition Grid::move
This property holds the transition to apply when moving an item within the positioner.
Positioner transitions will only affect the position (x,y) of items.
This can happen when other items are added or removed from the positioner, or
when items resize themselves.
\qml
Grid {
move: Transition {
NumberAnimation {
matchProperties: "x,y"
ease: "easeOutBounce"
}
}
}
\endqml
*/
/*!
\qmlproperty int Grid::spacing
spacing is the amount in pixels left empty between each adjacent
item, and defaults to 0.
The below example places a Grid containing a red, a blue and a
green rectangle on a gray background. The area the grid positioner
occupies is colored white. The top positioner has the default of no spacing,
and the bottom positioner has its spacing set to 2.
\image spacing_a.png
\image spacing_b.png
*/
/*!
\internal
\class QmlGraphicsGrid
\brief The QmlGraphicsGrid class lays out items in a grid.
\ingroup group_layouts
*/
QmlGraphicsGrid::QmlGraphicsGrid(QmlGraphicsItem *parent) :
QmlGraphicsBasePositioner(Both, parent)
{
_columns=-1;
_rows=-1;
}
/*!
\qmlproperty int Grid::columns
This property holds the number of columns in the grid.
When the columns property is set the Grid will always have
that many columns. Note that if you do not have enough items to
fill this many columns some columns will be of zero width.
*/
/*!
\qmlproperty int Grid::rows
This property holds the number of rows in the grid.
When the rows property is set the Grid will always have that
many rows. Note that if you do not have enough items to fill this
many rows some rows will be of zero width.
*/
void QmlGraphicsGrid::doPositioning()
{
int c=_columns,r=_rows;//Actual number of rows/columns
int numVisible = items()->size() + newItems()->size();
if (_columns==-1 && _rows==-1){
c = 4;
r = (numVisible+3)/4;
}else if (_rows==-1){
r = (numVisible+(_columns-1))/_columns;
}else if (_columns==-1){
c = (numVisible+(_rows-1))/_rows;
}
QList<int> maxColWidth;
QList<int> maxRowHeight;
int childIndex =0;
QList<QmlGraphicsItem *> children = positionedItems;
for (int i=0; i<r; i++){
for (int j=0; j<c; j++){
if (j==0)
maxRowHeight << 0;
if (i==0)
maxColWidth << 0;
if (childIndex == children.count())
continue;
QmlGraphicsItem *child = children.at(childIndex++);
if (!child || isInvisible(child))
continue;
if (child->width() > maxColWidth[j])
maxColWidth[j] = child->width();
if (child->height() > maxRowHeight[i])
maxRowHeight[i] = child->height();
}
}
int xoffset=0;
int yoffset=0;
int curRow =0;
int curCol =0;
foreach(QmlGraphicsItem* item, *leavingItems()){
if (remove()){
QList<QPair<QString,QVariant> > changes;
applyRemove(changes, item);
}
}
foreach(QmlGraphicsItem* child, children){
if (!child || isInvisible(child))
continue;
bool needMove = (child->x()!=xoffset)||(child->y()!=yoffset);
QList<QPair<QString, QVariant> > changes;
changes << qMakePair(QString(QLatin1String("x")),QVariant(xoffset));
changes << qMakePair(QString(QLatin1String("y")),QVariant(yoffset));
if (newItems()->contains(child) && add()) {
applyAdd(changes,child);
} else if (needMove) {
if (move()){
applyMove(changes,child);
}else{
setMovingItem(child);
child->setPos(QPointF(xoffset, yoffset));
setMovingItem(0);
}
}
xoffset+=maxColWidth[curCol]+spacing();
curCol++;
curCol%=c;
if (!curCol){
yoffset+=maxRowHeight[curRow]+spacing();
xoffset=0;
curRow++;
if (curRow>=r)
break;
}
}
}
QT_END_NAMESPACE
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