QQuickItem Class

Member Function Documentation

QQuickItem::QQuickItem(QQuickItem * parent = 0)

Constructs a QQuickItem with the given parent.

QQuickItem::~QQuickItem() [virtual]

Destroys the QQuickItem.

bool QQuickItem::acceptHoverEvents() const

See also setAcceptHoverEvents().

Qt::MouseButtons QQuickItem::acceptedMouseButtons() const

See also setAcceptedMouseButtons().

QQuickCanvas * QQuickItem::canvas() const

QQuickItem * QQuickItem::childAt(qreal x, qreal y) const

QList<QQuickItem *> QQuickItem::childItems() const

bool QQuickItem::childMouseEventFilter(QQuickItem *, QEvent *) [virtual protected]

void QQuickItem::classBegin() [virtual protected]

void QQuickItem::componentComplete() [virtual protected]

bool QQuickItem::contains(const QPointF & point) const [virtual]

Returns true if this item contains point, which is in local coordinates; returns false otherwise.

This function can be overwritten in order to handle point collisions in items with custom shapes. The default implementation checks if the point is inside the item's bounding rect.

Note that it's normally used to check if the item is under the mouse cursor, and for that reason, the implementation of this function should be as light-weight as possible.

void QQuickItem::dragEnterEvent(QDragEnterEvent *) [virtual protected]

void QQuickItem::dragLeaveEvent(QDragLeaveEvent *) [virtual protected]

void QQuickItem::dragMoveEvent(QDragMoveEvent *) [virtual protected]

void QQuickItem::dropEvent(QDropEvent *) [virtual protected]

bool QQuickItem::event(QEvent *) [virtual protected]

bool QQuickItem::filtersChildMouseEvents() const

See also setFiltersChildMouseEvents().

Flags QQuickItem::flags() const

See also setFlags().

void QQuickItem::focusInEvent(QFocusEvent *) [virtual protected]

void QQuickItem::focusOutEvent(QFocusEvent *) [virtual protected]

void QQuickItem::forceActiveFocus()

void QQuickItem::geometryChanged(const QRectF & newGeometry, const QRectF & oldGeometry) [virtual protected]

This function is called to handle this item's changes in geometry from oldGeometry to newGeometry. If the two geometries are the same, it doesn't do anything.

void QQuickItem::grabMouse()

void QQuickItem::grabTouchPoints(const QList<int> & ids)

Grabs the touch points specified by ids.

These touch points will be owned by the item until they are released. Alternatively, the grab can be stolen by a filtering item like Flickable. Use setKeepTouchGrab() to prevent the grab from being stolen.

See also ungrabTouchPoints() and setKeepTouchGrab().

bool QQuickItem::hasActiveFocus() const

bool QQuickItem::hasFocus() const

bool QQuickItem::heightValid() const [protected]

Returns whether the height property has been set explicitly.

void QQuickItem::hoverEnterEvent(QHoverEvent * event) [virtual protected]

void QQuickItem::hoverLeaveEvent(QHoverEvent * event) [virtual protected]

void QQuickItem::hoverMoveEvent(QHoverEvent * event) [virtual protected]

void QQuickItem::inputMethodEvent(QInputMethodEvent *) [virtual protected]

QVariant QQuickItem::inputMethodQuery(Qt::InputMethodQuery query) const [virtual]

bool QQuickItem::isComponentComplete() const [protected]

Returns true if construction of the QML component is complete; otherwise returns false.

It is often desirable to delay some processing until the component is completed.

See also componentComplete().

bool QQuickItem::isFocusScope() const

bool QQuickItem::isTextureProvider() const [virtual]

Returns true if this item is a texture provider. The default implementation returns false.

This function can be called from any thread.

bool QQuickItem::isUnderMouse() const

void QQuickItem::itemChange(ItemChange, const ItemChangeData &) [virtual protected]

QTransform QQuickItem::itemTransform(QQuickItem *, bool *) const

bool QQuickItem::keepMouseGrab() const

See also setKeepMouseGrab().

bool QQuickItem::keepTouchGrab() const

Returns a value indicating whether the touch points grabbed by this item should remain with this item exclusively.

See also setKeepTouchGrab() and keepMouseGrab().

void QQuickItem::keyPressEvent(QKeyEvent * event) [virtual protected]

void QQuickItem::keyReleaseEvent(QKeyEvent * event) [virtual protected]

QPointF QQuickItem::mapFromItem(const QQuickItem * item, const QPointF & point) const

void QQuickItem::mapFromItem(QQmlV8Function *) const

QPointF QQuickItem::mapFromScene(const QPointF & point) const

QRectF QQuickItem::mapRectFromItem(const QQuickItem * item, const QRectF & rect) const

QRectF QQuickItem::mapRectFromScene(const QRectF & rect) const

QRectF QQuickItem::mapRectToItem(const QQuickItem * item, const QRectF & rect) const

QRectF QQuickItem::mapRectToScene(const QRectF & rect) const

QPointF QQuickItem::mapToItem(const QQuickItem * item, const QPointF & point) const

void QQuickItem::mapToItem(QQmlV8Function *) const

QPointF QQuickItem::mapToScene(const QPointF & point) const

void QQuickItem::mouseDoubleClickEvent(QMouseEvent * event) [virtual protected]

void QQuickItem::mouseMoveEvent(QMouseEvent * event) [virtual protected]

void QQuickItem::mousePressEvent(QMouseEvent * event) [virtual protected]

void QQuickItem::mouseReleaseEvent(QMouseEvent * event) [virtual protected]

void QQuickItem::mouseUngrabEvent() [virtual protected]

void QQuickItem::polish()

void QQuickItem::releaseResources() [virtual protected]

This function is called when the item's scene graph resources are no longer needed. It allows items to free its resources, for instance textures, that are not owned by scene graph nodes. Note that scene graph nodes are managed by QQuickCanvas and should not be deleted by this function. Scene graph resources are no longer needed when the parent is set to null and the item is not used by any ShaderEffect or ShaderEffectSource.

This function is called from the main thread. Therefore, resources used by the scene graph should not be deleted directly, but by calling QObject::deleteLater().

Note: The item destructor still needs to free its scene graph resources if not already done.

QQuickItem * QQuickItem::scopedFocusItem() const

void QQuickItem::setAcceptHoverEvents(bool enabled)

See also acceptHoverEvents().

void QQuickItem::setAcceptedMouseButtons(Qt::MouseButtons buttons)

See also acceptedMouseButtons().

void QQuickItem::setFiltersChildMouseEvents(bool filter)

See also filtersChildMouseEvents().

void QQuickItem::setFlag(Flag flag, bool enabled = true)

void QQuickItem::setFlags(Flags flags)

See also flags().

void QQuickItem::setFocus(bool)

See also hasFocus().

void QQuickItem::setImplicitHeight(qreal h) [protected]

Sets the implied height of the item to h. This is the height implied by other properties that determine the content.

See also implicitHeight().

void QQuickItem::setImplicitSize(qreal, qreal) [protected]

void QQuickItem::setImplicitWidth(qreal w) [protected]

Sets the implied width of the item to w. This is the width implied by other properties that determine the content.

See also implicitWidth().

void QQuickItem::setKeepMouseGrab(bool keep)

The flag indicating whether the mouse should remain with this item is set to keep.

This is useful for items that wish to grab and keep mouse interaction following a predefined gesture. For example, an item that is interested in horizontal mouse movement may set keepMouseGrab to true once a threshold has been exceeded. Once keepMouseGrab has been set to true, filtering items will not react to mouse events.

If the item does not indicate that it wishes to retain mouse grab, a filtering item may steal the grab. For example, Flickable may attempt to steal a mouse grab if it detects that the user has begun to move the viewport.

See also keepMouseGrab().

void QQuickItem::setKeepTouchGrab(bool keep)

The flag indicating whether the touch points grabbed by this item should remain with this item is set to keep.

This is useful for items that wish to grab and keep specific touch points following a predefined gesture. For example, an item that is interested in horizontal touch point movement may set setKeepTouchGrab to true once a threshold has been exceeded. Once setKeepTouchGrab has been set to true, filtering items will not react to the relevant touch points.

If the item does not indicate that it wishes to retain touch point grab, a filtering item may steal the grab. For example, Flickable may attempt to steal a touch point grab if it detects that the user has begun to move the viewport.

See also keepTouchGrab() and setKeepMouseGrab().

void QQuickItem::setPos(const QPointF &)

See also pos().

void QQuickItem::setSize(const QSizeF & size)

void QQuickItem::setState(const QString &)

See also state().

void QQuickItem::setTransformOrigin(TransformOrigin)

See also transformOrigin().

void QQuickItem::setTransformOriginPoint(const QPointF &)

See also transformOriginPoint().

void QQuickItem::stackAfter(const QQuickItem *)

void QQuickItem::stackBefore(const QQuickItem *)

QString QQuickItem::state() const

See also setState().

QSGTextureProvider * QQuickItem::textureProvider() const [virtual]

Returns the texture provider for an item. The default implementation returns 0.

This function may only be called on the rendering thread.

void QQuickItem::touchEvent(QTouchEvent * event) [virtual protected]

void QQuickItem::touchUngrabEvent() [virtual protected]

QQmlListProperty<QQuickTransform> QQuickItem::transform()

TransformOrigin QQuickItem::transformOrigin() const

See also setTransformOrigin().

QPointF QQuickItem::transformOriginPoint() const

See also setTransformOriginPoint().

void QQuickItem::ungrabMouse()

void QQuickItem::ungrabTouchPoints()

Ungrabs the touch points owned by this item.

See also grabTouchPoints().

void QQuickItem::update() [slot]

Schedules a call to updatePaintNode() for this item.

The call to QQuickItem::updatePaintNode() will always happen if the item is showing in a QQuickCanvas.

Only items which specifies QQuickItem::ItemHasContents are allowed to call QQuickItem::update().

void QQuickItem::updateInputMethod(Qt::InputMethodQueries queries = Qt::ImQueryInput) [protected]

Notify input method on updated query values if needed. indicates changed attributes.

QSGNode * QQuickItem::updatePaintNode(QSGNode * oldNode, UpdatePaintNodeData *) [virtual protected]

Called by the rendering thread, as a result of QQuickItem::update(), when it is time to sync the state of the QML objects with the scene graph objects.

The function should return the root of the scene graph subtree for this item. Most implementations will return a single QSGGeometryNode containing the visual representation of this item. oldNode is the node that was returned the last time the function was called.

 QSGNode *MyItem::updatePaintNode(QSGNode *node, UpdatePaintNodeData *)
 {
     QSGSimpleRectNode *n = static_cast<QSGSimpleRectNode *>(node);
     if (!n) {
         n = new QSGSimpleRectNode();
         n->setColor(Qt::red);
     }
     n->setRect(boundingRect());
     return n;
 }

The main thread is blocked while this function is executed so it is safe to read values from the QQuickItem instance and other objects in the main thread.

If no call to QQuickItem::updatePaintNode() result in actual scene graph changes, like QSGNode::markDirty() or adding and removing nodes, then the underlying implementation may decide to not render the scene again as the visual outcome is identical.

Warning: It is crucial that OpenGL operations and interaction with the scene graph happens exclusively on the rendering thread, primarily during the QQuickItem::updatePaintNode() call. The best rule of thumb is to only use classes with the "QSG" prefix inside the QQuickItem::updatePaintNode() function.

See also QSGMaterial, QSGSimpleMaterial, QSGGeometryNode, QSGGeometry, QSGFlatColorMaterial, QSGTextureMaterial, and QSGNode::markDirty().

void QQuickItem::updatePolish() [virtual protected]

void QQuickItem::wheelEvent(QWheelEvent * event) [virtual protected]

bool QQuickItem::widthValid() const [protected]

Returns whether the width property has been set explicitly.

void QQuickItem::windowDeactivateEvent() [virtual protected]