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-rw-r--r--src/quick/handlers/qquickdraghandler.cpp142
1 files changed, 88 insertions, 54 deletions
diff --git a/src/quick/handlers/qquickdraghandler.cpp b/src/quick/handlers/qquickdraghandler.cpp
index 12f1a29bca..041780257a 100644
--- a/src/quick/handlers/qquickdraghandler.cpp
+++ b/src/quick/handlers/qquickdraghandler.cpp
@@ -53,20 +53,21 @@ QT_BEGIN_NAMESPACE
DragHandler is a handler that is used to interactively move an Item.
Like other Pointer Handlers, by default it is fully functional, and
- manipulates its \l target.
+ manipulates its \l {PointerHandler::target} {target}.
\snippet pointerHandlers/dragHandler.qml 0
It has properties to restrict the range of dragging.
- If it is declared within one Item but is assigned a different \l target,
- then it handles events within the bounds of the \l parent Item but
+ If it is declared within one Item but is assigned a different
+ \l {PointerHandler::target} {target}, then it handles events within the
+ bounds of the \l {PointerHandler::parent} {parent} Item but
manipulates the \c target Item instead:
\snippet pointerHandlers/dragHandlerDifferentTarget.qml 0
- A third way to use it is to set \l target to \c null and react to property
- changes in some other way:
+ A third way to use it is to set \l {PointerHandler::target} {target} to
+ \c null and react to property changes in some other way:
\snippet pointerHandlers/dragHandlerNullTarget.qml 0
@@ -91,19 +92,44 @@ bool QQuickDragHandler::wantsEventPoint(QQuickEventPoint *point)
|| QQuickSinglePointHandler::wantsEventPoint(point));
}
+bool QQuickDragHandler::targetContains(QQuickEventPoint *point)
+{
+ Q_ASSERT(parentItem() && target());
+ return target()->contains(localTargetPosition(point));
+}
+
+QPointF QQuickDragHandler::localTargetPosition(QQuickEventPoint *point)
+{
+ QPointF pos = point->position();
+ if (target() != parentItem())
+ pos = parentItem()->mapToItem(target(), pos);
+ return pos;
+}
+
void QQuickDragHandler::onGrabChanged(QQuickPointerHandler *grabber, QQuickEventPoint::GrabState stateChange, QQuickEventPoint *point)
{
- if (grabber == this && stateChange == QQuickEventPoint::GrabExclusive)
- // In case the grab got handled over from another grabber, we might not get the Press
- initializeTargetStartPos(point);
- enforceConstraints();
+ if (grabber == this && stateChange == QQuickEventPoint::GrabExclusive) {
+ // In case the grab got handed over from another grabber, we might not get the Press.
+ if (!m_pressedInsideTarget) {
+ if (target())
+ m_pressTargetPos = QPointF(target()->width(), target()->height()) / 2;
+ m_pressScenePos = point->scenePosition();
+ } else if (m_pressTargetPos.isNull()) {
+ if (target())
+ m_pressTargetPos = localTargetPosition(point);
+ m_pressScenePos = point->scenePosition();
+ }
+ }
QQuickSinglePointHandler::onGrabChanged(grabber, stateChange, point);
}
void QQuickDragHandler::onActiveChanged()
{
- if (!active())
- m_targetStartPos = QPointF();
+ if (!active()) {
+ m_pressTargetPos = QPointF();
+ m_pressScenePos = m_pressTargetPos;
+ m_pressedInsideTarget = false;
+ }
}
void QQuickDragHandler::handleEventPoint(QQuickEventPoint *point)
@@ -111,25 +137,40 @@ void QQuickDragHandler::handleEventPoint(QQuickEventPoint *point)
point->setAccepted();
switch (point->state()) {
case QQuickEventPoint::Pressed:
- initializeTargetStartPos(point);
+ if (target()) {
+ m_pressedInsideTarget = targetContains(point);
+ m_pressTargetPos = localTargetPosition(point);
+ }
+ m_pressScenePos = point->scenePosition();
setPassiveGrab(point);
break;
case QQuickEventPoint::Updated: {
- QPointF delta = point->scenePosition() - point->scenePressPosition();
- if (!m_xAxis.enabled())
- delta.setX(0);
- if (!m_yAxis.enabled())
- delta.setY(0);
+ QVector2D accumulatedDragDelta = QVector2D(point->scenePosition() - m_pressScenePos);
if (active()) {
- setTranslation(QVector2D(delta));
+ // update translation property. Make sure axis is respected for it.
+ if (!m_xAxis.enabled())
+ accumulatedDragDelta.setX(0);
+ if (!m_yAxis.enabled())
+ accumulatedDragDelta.setY(0);
+ setTranslation(accumulatedDragDelta);
+
if (target() && target()->parentItem()) {
- QPointF pos = target()->parentItem()->mapFromScene(m_targetStartPos + delta);
+ const QPointF newTargetTopLeft = localTargetPosition(point) - m_pressTargetPos;
+ const QPointF xformOrigin = target()->transformOriginPoint();
+ const QPointF targetXformOrigin = newTargetTopLeft + xformOrigin;
+ QPointF pos = target()->parentItem()->mapFromItem(target(), targetXformOrigin);
+ pos -= xformOrigin;
+ QPointF targetItemPos = target()->position();
+ if (!m_xAxis.enabled())
+ pos.setX(targetItemPos.x());
+ if (!m_yAxis.enabled())
+ pos.setY(targetItemPos.y());
enforceAxisConstraints(&pos);
moveTarget(pos, point);
}
} else if (!point->exclusiveGrabber() &&
- ((m_xAxis.enabled() && QQuickWindowPrivate::dragOverThreshold(delta.x(), Qt::XAxis, point)) ||
- (m_yAxis.enabled() && QQuickWindowPrivate::dragOverThreshold(delta.y(), Qt::YAxis, point)))) {
+ ((m_xAxis.enabled() && QQuickWindowPrivate::dragOverThreshold(accumulatedDragDelta.x(), Qt::XAxis, point)) ||
+ (m_yAxis.enabled() && QQuickWindowPrivate::dragOverThreshold(accumulatedDragDelta.y(), Qt::YAxis, point)))) {
setExclusiveGrab(point);
if (auto parent = parentItem()) {
if (point->pointerEvent()->asPointerTouchEvent())
@@ -165,23 +206,6 @@ void QQuickDragHandler::enforceAxisConstraints(QPointF *localPos)
localPos->setY(qBound(m_yAxis.minimum(), localPos->y(), m_yAxis.maximum()));
}
-void QQuickDragHandler::initializeTargetStartPos(QQuickEventPoint *point)
-{
- if (target() && target()->parentItem() && m_targetStartPos.isNull()) { // prefer the m_targetStartPos we got when it got Pressed.
- m_targetStartPos = target()->parentItem()->mapToScene(target()->position());
- if (!target()->contains(point->position())) {
- // If pressed outside of target item, move the target item so that the touchpoint is in its center,
- // while still respecting the axis constraints.
- const QPointF center = target()->parentItem()->mapFromScene(point->scenePosition());
- const QPointF pointCenteredInItemPos = target()->parentItem()->mapToScene(center - QPointF(target()->width(), target()->height())/2);
- if (m_xAxis.enabled())
- m_targetStartPos.setX(pointCenteredInItemPos.x());
- if (m_yAxis.enabled())
- m_targetStartPos.setY(pointCenteredInItemPos.y());
- }
- }
-}
-
void QQuickDragHandler::setTranslation(const QVector2D &trans)
{
if (trans == m_translation) // fuzzy compare?
@@ -192,23 +216,33 @@ void QQuickDragHandler::setTranslation(const QVector2D &trans)
/*!
\qmlpropertygroup QtQuick::DragHandler::xAxis
+ \qmlproperty real QtQuick::DragHandler::xAxis.minimum
+ \qmlproperty real QtQuick::DragHandler::xAxis.maximum
+ \qmlproperty bool QtQuick::DragHandler::xAxis.enabled
+
+ \c xAxis controls the constraints for horizontal dragging.
+
+ \c minimum is the minimum acceptable value of \l {Item::x}{x} to be
+ applied to the \l {PointerHandler::target} {target}.
+ \c maximum is the maximum acceptable value of \l {Item::x}{x} to be
+ applied to the \l {PointerHandler::target} {target}.
+ If \c enabled is true, horizontal dragging is allowed.
+ */
+
+/*!
\qmlpropertygroup QtQuick::DragHandler::yAxis
- \qmlproperty real QtQuick::DragHandler::DragAxis::minimum
- \qmlproperty real QtQuick::DragHandler::DragAxis::maximum
- \qmlproperty real QtQuick::DragHandler::DragAxis::enabled
-
- \c xAxis and yAxis control the constraints for horizontal and vertical
- dragging, respectively.
-
- \value minimum
- The minimum acceptable value of \l {Item::x}{x} or \l {Item::y}{y}
- to be applied to the \l target
- \value maximum
- The maximum acceptable value of \l {Item::x}{x} or \l {Item::y}{y}
- to be applied to the \l target
- \value enabled
- Whether dragging in this direction is allowed at all
-*/
+ \qmlproperty real QtQuick::DragHandler::yAxis.minimum
+ \qmlproperty real QtQuick::DragHandler::yAxis.maximum
+ \qmlproperty bool QtQuick::DragHandler::yAxis.enabled
+
+ \c yAxis controls the constraints for vertical dragging.
+
+ \c minimum is the minimum acceptable value of \l {Item::y}{y} to be
+ applied to the \l {PointerHandler::target} {target}.
+ \c maximum is the maximum acceptable value of \l {Item::y}{y} to be
+ applied to the \l {PointerHandler::target} {target}.
+ If \c enabled is true, vertical dragging is allowed.
+ */
QQuickDragAxis::QQuickDragAxis()
: m_minimum(-DBL_MAX)
, m_maximum(DBL_MAX)
generated by cgit v1.2.3 (git 2.25.1) at 2024-06-19 17:10:22 +0000