void KItemListSmoothScroller::scrollContentsBy(qreal distance)
{
QObject* target = targetObject();
if (!target) {
return;
}
const QByteArray name = propertyName();
const qreal currentOffset = target->property(name).toReal();
if (static_cast<int>(currentOffset) == m_scrollBar->value()) {
// The current offset is already synchronous to the scrollbar
return;
}
const bool animRunning = (m_animation->state() == QAbstractAnimation::Running);
if (animRunning) {
// Stopping a running animation means skipping the range from the current offset
// until the target offset. To prevent skipping of the range the difference
// is added to the new target offset.
const qreal oldEndOffset = m_animation->endValue().toReal();
distance += (currentOffset - oldEndOffset);
}
const qreal endOffset = currentOffset - distance;
if (m_smoothScrolling || animRunning) {
qreal startOffset = currentOffset;
if (animRunning) {
// If the animation was running and has been interrupted by assigning a new end-offset
// one frame must be added to the start-offset to keep the animation smooth. This also
// assures that animation proceeds even in cases where new end-offset are triggered
// within a very short timeslots.
startOffset += (endOffset - currentOffset) * 1000 / (m_animation->duration() * 60);
if (currentOffset < endOffset) {
startOffset = qMin(startOffset, endOffset);
} else {
startOffset = qMax(startOffset, endOffset);
}
}
m_animation->stop();
m_animation->setStartValue(startOffset);
m_animation->setEndValue(endOffset);
m_animation->setEasingCurve(animRunning ? QEasingCurve::OutQuad : QEasingCurve::InOutQuad);
m_animation->start();
target->setProperty(name, startOffset);
} else {
target->setProperty(name, endOffset);
}
}
int QPropertyAnimation::qt_metacall(QMetaObject::Call _c, int _id, void **_a)
{
_id = QVariantAnimation::qt_metacall(_c, _id, _a);
if (_id < 0)
return _id;
#ifndef QT_NO_PROPERTIES
if (_c == QMetaObject::ReadProperty) {
void *_v = _a[0];
switch (_id) {
case 0:
*reinterpret_cast< QByteArray*>(_v) = propertyName();
break;
case 1:
*reinterpret_cast< QObject**>(_v) = targetObject();
break;
}
_id -= 2;
} else if (_c == QMetaObject::WriteProperty) {
void *_v = _a[0];
switch (_id) {
case 0:
setPropertyName(*reinterpret_cast< QByteArray*>(_v));
break;
case 1:
setTargetObject(*reinterpret_cast< QObject**>(_v));
break;
}
_id -= 2;
} else if (_c == QMetaObject::ResetProperty) {
_id -= 2;
} else if (_c == QMetaObject::QueryPropertyDesignable) {
_id -= 2;
} else if (_c == QMetaObject::QueryPropertyScriptable) {
_id -= 2;
} else if (_c == QMetaObject::QueryPropertyStored) {
_id -= 2;
} else if (_c == QMetaObject::QueryPropertyEditable) {
_id -= 2;
} else if (_c == QMetaObject::QueryPropertyUser) {
_id -= 2;
}
#endif // QT_NO_PROPERTIES
return _id;
}
MyPropertyAnimation::~MyPropertyAnimation(){
delete targetObject();
}
