path: root/src/corelib/animation/qanimationgroup.cpp

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/*!
    \class QAnimationGroup
    \brief The QAnimationGroup is an abstract base class for group of animations.
    \since 4.5
    \ingroup animation
    \preliminary

    QAnimationGroup represents a group of animations, such as parallel or sequential,
    and lets you combine different animations into one. The group manages any animation
    that inherits QAbstractAnimation. By combining groups, you can easily construct
    complex animation graphs.

    The QAnimationGroup base class provides methods for adding and retrieving animations.
    Besides that, you can remove animations by calling remove(), and clear the animation
    group by calling clearAnimations(). You may keep track of changes in the group's animations by
    listening to QEvent::ChildAdded and QEvent::ChildRemoved events.

    QAnimationGroup takes ownership of the animations it manages, and ensures that they are
    deleted when the animation group is deleted.

    \sa QAbstractAnimation, QVariantAnimation, {The Animation Framework}
*/

#ifndef QT_NO_ANIMATION

#include "qanimationgroup.h"
#include <QtCore/qdebug.h>
#include <QtCore/qcoreevent.h>
#include "qanimationgroup_p.h"

QT_BEGIN_NAMESPACE


/*!
    Constructs a QAnimationGroup.
    \a parent is passed to QObject's constructor.
*/
QAnimationGroup::QAnimationGroup(QObject *parent)
    : QAbstractAnimation(*new QAnimationGroupPrivate, parent)
{
}

/*!
    \internal
*/
QAnimationGroup::QAnimationGroup(QAnimationGroupPrivate &dd, QObject *parent)
    : QAbstractAnimation(dd, parent)
{
}

/*!
    Destroys the animation group. It will also destroy all its animations.
*/
QAnimationGroup::~QAnimationGroup()
{
}

/*!
    Returns a pointer to the animation at \a index in this group. This
    function is useful when you need access to a particular animation.  \a
    index is between 0 and animationCount() - 1.

    \sa animationCount(), indexOfAnimation()
*/
QAbstractAnimation *QAnimationGroup::animationAt(int index) const
{
    Q_D(const QAnimationGroup);

    if (index < 0 || index >= d->animations.size()) {
        qWarning("QAnimationGroup::animationAt: index is out of bounds");
        return 0;
    }

    return d->animations.at(index);
}


/*!
    Returns the number of animations managed by this group.

    \sa indexOfAnimation(), addAnimation(), animationAt()
*/
int QAnimationGroup::animationCount() const
{
    Q_D(const QAnimationGroup);
    return d->animations.size();
}

/*!
    Returns the index of \a animation. The returned index can be passed
    to the other functions that take an index as an argument.

    \sa insertAnimationAt() animationAt(), takeAnimationAt()
*/
int QAnimationGroup::indexOfAnimation(QAbstractAnimation *animation) const
{
    Q_D(const QAnimationGroup);
    return d->animations.indexOf(animation);
}

/*!
    Adds \a animation to this group. This will call insertAnimationAt with
    index equals to animationCount()
*/
void QAnimationGroup::addAnimation(QAbstractAnimation *animation)
{
    Q_D(QAnimationGroup);
    insertAnimationAt(d->animations.count(), animation);
}

/*!
    Inserts \a animation into this animation group at \a index.
    If \a index is 0 the animation is inserted at the beginning.
    If \a index is animationCount(), the animation is inserted at the end.
    \sa takeAnimationAt(), addAnimation(), indexOfAnimation()
*/
void QAnimationGroup::insertAnimationAt(int index, QAbstractAnimation *animation)
{
    Q_D(QAnimationGroup);

    if (index < 0 || index > d->animations.size()) {
        qWarning("QAnimationGroup::insertAnimationAt: index is out of bounds");
        return;
    }

    if (QAnimationGroup *oldGroup = animation->group())
        oldGroup->removeAnimation(animation);

    d->animations.insert(index, animation);
    QAbstractAnimationPrivate::get(animation)->group = this;
    // this will make sure that ChildAdded event is sent to 'this'
    animation->setParent(this);
    d->animationInsertedAt(index);
}

/*!
    Removes \a animation from this group. The ownership of \a animation is
    transferred to the caller.

    \sa takeAnimationAt(), insertAnimationAt(), addAnimation()
*/
void QAnimationGroup::removeAnimation(QAbstractAnimation *animation)
{
    Q_D(QAnimationGroup);

    if (!animation) {
        qWarning("QAnimationGroup::remove: cannot remove null animation");
        return;
    }
    int index = d->animations.indexOf(animation);
    if (index == -1) {
        qWarning("QAnimationGroup::remove: animation is not part of this group");
        return;
    }

    takeAnimationAt(index);
}

/*!
    Removes the animation at \a index from this animation group. The ownership
    of the animation is transferred to the caller, and a pointer to the removed
    animation is returned.

    \sa addAnimation()
*/
QAbstractAnimation *QAnimationGroup::takeAnimationAt(int index)
{
    Q_D(QAnimationGroup);
    if (index < 0 || index >= d->animations.size()) {
        qWarning("QAnimationGroup::takeAnimationAt: no animation at index %d", index);
        return 0;
    }
    QAbstractAnimation *animation = d->animations.at(index);
    QAbstractAnimationPrivate::get(animation)->group = 0;
    // ### removing from list before doing setParent to avoid inifinite recursion
    // in ChildRemoved event
    d->animations.removeAt(index);
    animation->setParent(0);
    d->animationRemovedAt(index);
    return animation;
}

/*!
    Removes and deletes all animations in this animation group, and resets the current
    time to 0.

    \sa addAnimation(), removeAnimation()
*/
void QAnimationGroup::clearAnimations()
{
    Q_D(QAnimationGroup);
    qDeleteAll(d->animations);
}

/*!
    \reimp
*/
bool QAnimationGroup::event(QEvent *event)
{
    Q_D(QAnimationGroup);
    if (event->type() == QEvent::ChildAdded) {
        QChildEvent *childEvent = static_cast<QChildEvent *>(event);
        if (QAbstractAnimation *a = qobject_cast<QAbstractAnimation *>(childEvent->child())) {
            if (a->group() != this)
                addAnimation(a);
        }
    } else if (event->type() == QEvent::ChildRemoved) {
        QChildEvent *childEvent = static_cast<QChildEvent *>(event);
        QAbstractAnimation *a = static_cast<QAbstractAnimation *>(childEvent->child());
        // You can only rely on the child being a QObject because in the QEvent::ChildRemoved
        // case it might be called from the destructor.
        int index = d->animations.indexOf(a);
        if (index != -1)
            takeAnimationAt(index);
    }
    return QAbstractAnimation::event(event);
}


void QAnimationGroupPrivate::animationRemovedAt(int index)
{
    Q_Q(QAnimationGroup);
    Q_UNUSED(index);
    if (animations.isEmpty()) {
        currentTime = 0;
        q->stop();
    }
}

QT_END_NAMESPACE

#include "moc_qanimationgroup.cpp"

#endif //QT_NO_ANIMATION