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Diffstat (limited to 'src/quick/items/qquickflipable.cpp')
-rw-r--r-- | src/quick/items/qquickflipable.cpp | 308 |
1 files changed, 308 insertions, 0 deletions
diff --git a/src/quick/items/qquickflipable.cpp b/src/quick/items/qquickflipable.cpp new file mode 100644 index 0000000000..ed89f2aaf5 --- /dev/null +++ b/src/quick/items/qquickflipable.cpp @@ -0,0 +1,308 @@ +/**************************************************************************** +** +** Copyright (C) 2011 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. +** +** $QT_BEGIN_LICENSE:LGPL$ +** GNU Lesser General Public License Usage +** 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. +** +** GNU General Public License Usage +** Alternatively, this file may be used under the terms of the GNU General +** Public License version 3.0 as published by the Free Software Foundation +** and appearing in the file LICENSE.GPL included in the packaging of this +** file. Please review the following information to ensure the GNU General +** Public License version 3.0 requirements will be met: +** http://www.gnu.org/copyleft/gpl.html. +** +** Other Usage +** Alternatively, this file may be used in accordance with the terms and +** conditions contained in a signed written agreement between you and Nokia. +** +** +** +** +** +** $QT_END_LICENSE$ +** +****************************************************************************/ + +#include "qquickflipable_p.h" +#include "qquickitem_p.h" + +#include <private/qdeclarativeguard_p.h> + +#include <QtDeclarative/qdeclarativeinfo.h> + +QT_BEGIN_NAMESPACE + +// XXX todo - i think this needs work and a bit of a re-think + +class QQuickLocalTransform : public QQuickTransform +{ + Q_OBJECT +public: + QQuickLocalTransform(QObject *parent) : QQuickTransform(parent) {} + + void setTransform(const QTransform &t) { + transform = t; + update(); + } + virtual void applyTo(QMatrix4x4 *matrix) const { + *matrix *= transform; + } +private: + QTransform transform; +}; + +class QQuickFlipablePrivate : public QQuickItemPrivate +{ + Q_DECLARE_PUBLIC(QQuickFlipable) +public: + QQuickFlipablePrivate() : current(QQuickFlipable::Front), front(0), back(0), sideDirty(false) {} + + virtual void transformChanged(); + void updateSide(); + void setBackTransform(); + + QQuickFlipable::Side current; + QDeclarativeGuard<QQuickLocalTransform> backTransform; + QDeclarativeGuard<QQuickItem> front; + QDeclarativeGuard<QQuickItem> back; + + bool sideDirty; + bool wantBackXFlipped; + bool wantBackYFlipped; +}; + +/*! + \qmlclass Flipable QQuickFlipable + \inqmlmodule QtQuick 2 + \ingroup qml-basic-interaction-elements + \brief The Flipable item provides a surface that can be flipped. + \inherits Item + + Flipable is an item that can be visibly "flipped" between its front and + back sides, like a card. It is used together with \l Rotation, \l State + and \l Transition elements to produce a flipping effect. + + The \l front and \l back properties are used to hold the items that are + shown respectively on the front and back sides of the flipable item. + + \section1 Example Usage + + The following example shows a Flipable item that flips whenever it is + clicked, rotating about the y-axis. + + This flipable item has a \c flipped boolean property that is toggled + whenever the MouseArea within the flipable is clicked. When + \c flipped is true, the item changes to the "back" state; in this + state, the \c angle of the \l Rotation item is changed to 180 + degrees to produce the flipping effect. When \c flipped is false, the + item reverts to the default state, in which the \c angle value is 0. + + \snippet doc/src/snippets/declarative/flipable/flipable.qml 0 + + \image flipable.gif + + The \l Transition creates the animation that changes the angle over + four seconds. When the item changes between its "back" and + default states, the NumberAnimation animates the angle between + its old and new values. + + See \l {QML States} for details on state changes and the default + state, and \l {QML Animation and Transitions} for more information on how + animations work within transitions. + + \sa {declarative/ui-components/flipable}{Flipable example} +*/ +QQuickFlipable::QQuickFlipable(QQuickItem *parent) +: QQuickItem(*(new QQuickFlipablePrivate), parent) +{ +} + +QQuickFlipable::~QQuickFlipable() +{ +} + +/*! + \qmlproperty Item QtQuick2::Flipable::front + \qmlproperty Item QtQuick2::Flipable::back + + The front and back sides of the flipable. +*/ + +QQuickItem *QQuickFlipable::front() +{ + Q_D(const QQuickFlipable); + return d->front; +} + +void QQuickFlipable::setFront(QQuickItem *front) +{ + Q_D(QQuickFlipable); + if (d->front) { + qmlInfo(this) << tr("front is a write-once property"); + return; + } + d->front = front; + d->front->setParentItem(this); + if (Back == d->current) + d->front->setOpacity(0.); + emit frontChanged(); +} + +QQuickItem *QQuickFlipable::back() +{ + Q_D(const QQuickFlipable); + return d->back; +} + +void QQuickFlipable::setBack(QQuickItem *back) +{ + Q_D(QQuickFlipable); + if (d->back) { + qmlInfo(this) << tr("back is a write-once property"); + return; + } + if (back == 0) + return; + d->back = back; + d->back->setParentItem(this); + + d->backTransform = new QQuickLocalTransform(d->back); + d->backTransform->prependToItem(d->back); + + if (Front == d->current) + d->back->setOpacity(0.); + connect(back, SIGNAL(widthChanged()), + this, SLOT(retransformBack())); + connect(back, SIGNAL(heightChanged()), + this, SLOT(retransformBack())); + emit backChanged(); +} + +void QQuickFlipable::retransformBack() +{ + Q_D(QQuickFlipable); + if (d->current == QQuickFlipable::Back && d->back) + d->setBackTransform(); +} + +/*! + \qmlproperty enumeration QtQuick2::Flipable::side + + The side of the Flipable currently visible. Possible values are \c + Flipable.Front and \c Flipable.Back. +*/ +QQuickFlipable::Side QQuickFlipable::side() const +{ + Q_D(const QQuickFlipable); + + const_cast<QQuickFlipablePrivate *>(d)->updateSide(); + return d->current; +} + +void QQuickFlipablePrivate::transformChanged() +{ + Q_Q(QQuickFlipable); + + if (!sideDirty) { + sideDirty = true; + q->polish(); + } + + QQuickItemPrivate::transformChanged(); +} + +void QQuickFlipable::updatePolish() +{ + Q_D(QQuickFlipable); + d->updateSide(); +} + +// determination on the currently visible side of the flipable +// has to be done on the complete scene transform to give +// correct results. +void QQuickFlipablePrivate::updateSide() +{ + Q_Q(QQuickFlipable); + + if (!sideDirty) + return; + + sideDirty = false; + + QTransform sceneTransform; + itemToParentTransform(sceneTransform); + + QPointF p1(0, 0); + QPointF p2(1, 0); + QPointF p3(1, 1); + + QPointF scenep1 = sceneTransform.map(p1); + QPointF scenep2 = sceneTransform.map(p2); + QPointF scenep3 = sceneTransform.map(p3); +#if 0 + p1 = q->mapToParent(p1); + p2 = q->mapToParent(p2); + p3 = q->mapToParent(p3); +#endif + + qreal cross = (scenep1.x() - scenep2.x()) * (scenep3.y() - scenep2.y()) - + (scenep1.y() - scenep2.y()) * (scenep3.x() - scenep2.x()); + + wantBackYFlipped = scenep1.x() >= scenep2.x(); + wantBackXFlipped = scenep2.y() >= scenep3.y(); + + QQuickFlipable::Side newSide; + if (cross > 0) { + newSide = QQuickFlipable::Back; + } else { + newSide = QQuickFlipable::Front; + } + + if (newSide != current) { + current = newSide; + if (current == QQuickFlipable::Back && back) + setBackTransform(); + if (front) + front->setOpacity((current==QQuickFlipable::Front)?1.:0.); + if (back) + back->setOpacity((current==QQuickFlipable::Back)?1.:0.); + emit q->sideChanged(); + } +} + +/* Depends on the width/height of the back item, and so needs reevaulating + if those change. +*/ +void QQuickFlipablePrivate::setBackTransform() +{ + QTransform mat; + mat.translate(back->width()/2,back->height()/2); + if (back->width() && wantBackYFlipped) + mat.rotate(180, Qt::YAxis); + if (back->height() && wantBackXFlipped) + mat.rotate(180, Qt::XAxis); + mat.translate(-back->width()/2,-back->height()/2); + + if (backTransform) + backTransform->setTransform(mat); +} + +QT_END_NAMESPACE + +#include "qquickflipable.moc" |