Qt Jambi Home

com.trolltech.qt.gui
Class QAbstractGraphicsShapeItem

java.lang.Object
  extended by com.trolltech.qt.QSignalEmitter
      extended by com.trolltech.qt.QtJambiObject
          extended by com.trolltech.qt.gui.QAbstractGraphicsShapeItem
All Implemented Interfaces:
QGraphicsItemInterface, QtJambiInterface
Direct Known Subclasses:
QGraphicsEllipseItem, QGraphicsPathItem, QGraphicsPolygonItem, QGraphicsRectItem, QGraphicsSimpleTextItem

public abstract class QAbstractGraphicsShapeItem
extends QtJambiObject
implements QGraphicsItemInterface

The QAbstractGraphicsShapeItem class provides a common base for all path items.

This class does not fully implement an item by itself; in particular, it does not implement boundingRect and paint, which are inherited by QGraphicsItem.

You can subclass this item to provide a simple base implementation of accessors for the item's pen and brush.

See Also:
QGraphicsRectItem, QGraphicsEllipseItem, QGraphicsPathItem, QGraphicsPolygonItem, QGraphicsTextItem, QGraphicsLineItem, QGraphicsPixmapItem, The Graphics View Framework

Nested Class Summary
 
Nested classes/interfaces inherited from class com.trolltech.qt.QSignalEmitter
QSignalEmitter.AbstractSignal, QSignalEmitter.Signal0, QSignalEmitter.Signal1<A>, QSignalEmitter.Signal2<A,B>, QSignalEmitter.Signal3<A,B,C>, QSignalEmitter.Signal4<A,B,C,D>, QSignalEmitter.Signal5<A,B,C,D,E>, QSignalEmitter.Signal6<A,B,C,D,E,F>, QSignalEmitter.Signal7<A,B,C,D,E,F,G>, QSignalEmitter.Signal8<A,B,C,D,E,F,G,H>, QSignalEmitter.Signal9<A,B,C,D,E,F,G,H,I>
 
Constructor Summary
QAbstractGraphicsShapeItem()
          Constructs a parentless QAbstractGraphicsShapeItem.
QAbstractGraphicsShapeItem(QGraphicsItemInterface parent)
          Constructs a QAbstractGraphicsShapeItem.
QAbstractGraphicsShapeItem(QGraphicsItemInterface parent, QGraphicsScene scene)
          Constructs a new QAbstractGraphicsShapeItem with the specified parent and adds it to scene.
 
Method Summary
 boolean acceptDrops()
          Returns true if this item can accept drag and drop events; otherwise, returns false.
 Qt.MouseButtons acceptedMouseButtons()
          Returns the mouse buttons that this item accepts mouse events for.
 boolean acceptsHoverEvents()
          Returns true if an item accepts hover events (QGraphicsSceneHoverEvent); otherwise, returns false.
 void addToIndex()
          
 void advance(int phase)
          This virtual function is called twice for all items by the QGraphicsScene::advance() slot.
abstract  QRectF boundingRect()
          This pure virtual function defines the outer bounds of the item as a rectangle; all painting must be restricted to inside an item's bounding rect.
 QBrush brush()
          Returns the item's brush, or an empty brush if no brush has been set.
 java.util.List<QGraphicsItemInterface> childItems()
          Returns a list of this item's children.
 QRectF childrenBoundingRect()
          Returns the bounding rect of this item's descendents (i.e., its children, their children, etc.) in local coordinates.
 void clearFocus()
          Takes keyboard input focus from the item.
 boolean collidesWithItem(QGraphicsItemInterface other, Qt.ItemSelectionMode mode)
          Returns true if this item collides with other; otherwise returns false.
 boolean collidesWithPath(QPainterPath path, Qt.ItemSelectionMode mode)
          Returns true if this item collides with path.
 java.util.List<QGraphicsItemInterface> collidingItems(Qt.ItemSelectionMode mode)
          Returns a list of all items that collide with this item.
 boolean contains(QPointF point)
          Returns true if this item contains point, which is in local coordinates; otherwise, false is returned.
 void contextMenuEvent(QGraphicsSceneContextMenuEvent event)
          This event handler can be reimplemented in a subclass to process context menu events.
 QCursor cursor()
          Returns the current cursor shape for the item.
 java.lang.Object data(int key)
          Returns this item's custom data for the key key as a QVariant.
 QTransform deviceTransform(QTransform viewportTransform)
          Returns this item's device transformation matrix, using viewportTransform to map from scene to device coordinates.
 void dragEnterEvent(QGraphicsSceneDragDropEvent event)
          This event handler, for event event, can be reimplemented to receive drag enter events for this item.
 void dragLeaveEvent(QGraphicsSceneDragDropEvent event)
          This event handler, for event event, can be reimplemented to receive drag leave events for this item.
 void dragMoveEvent(QGraphicsSceneDragDropEvent event)
          This event handler, for event event, can be reimplemented to receive drag move events for this item.
 void dropEvent(QGraphicsSceneDragDropEvent event)
          This event handler, for event event, can be reimplemented to receive drop events for this item.
 void ensureVisible(double x, double y, double w, double h, int xmargin, int ymargin)
          This convenience function is equivalent to calling ensureVisible(QRectF(x, y, w, h), xmargin, ymargin):
 void ensureVisible(QRectF rect, int xmargin, int ymargin)
          If this item is part of a scene that is viewed by a QGraphicsView, this convenience function will attempt to scroll the view to ensure that rect is visible inside the view's viewport.
 java.lang.Object extension(java.lang.Object variant)
          
 QGraphicsItem.GraphicsItemFlags flags()
          Returns this item's flags.
 void focusInEvent(QFocusEvent event)
          This event handler, for event event, can be reimplemented to receive focus in events for this item.
 void focusOutEvent(QFocusEvent event)
          This event handler, for event event, can be reimplemented to receive focus out events for this item.
static QAbstractGraphicsShapeItem fromNativePointer(QNativePointer nativePointer)
          This function returns the QAbstractGraphicsShapeItem instance pointed to by nativePointer
 QGraphicsItemGroup group()
          Returns a pointer to this item's item group, or 0 if this item is not member of a group.
 boolean handlesChildEvents()
          Returns true if this item handles child events (i.e., all events intended for any of its children are instead sent to this item); otherwise, false is returned.
 boolean hasCursor()
          Returns true if this item has a cursor set; otherwise, false is returned.
 boolean hasFocus()
          Returns true if this item has focus (i.e., can accept key events); otherwise, returns false.
 void hide()
          Hides the item.
 void hoverEnterEvent(QGraphicsSceneHoverEvent event)
          This event handler, for event event, can be reimplemented to receive hover enter events for this item.
 void hoverLeaveEvent(QGraphicsSceneHoverEvent event)
          This event handler, for event event, can be reimplemented to receive hover leave events for this item.
 void hoverMoveEvent(QGraphicsSceneHoverEvent event)
          This event handler, for event event, can be reimplemented to receive hover move events for this item.
 void inputMethodEvent(QInputMethodEvent event)
          This event handler, for event event, can be reimplemented to receive input method events for this item.
 java.lang.Object inputMethodQuery(Qt.InputMethodQuery query)
          This method is only relevant for input items.
 void installSceneEventFilter(QGraphicsItemInterface filterItem)
          Installs an event filter for this item on filterItem, causing all events for this item to first pass through filterItem's sceneEventFilter function.
 boolean isAncestorOf(QGraphicsItemInterface child)
          Returns true if this item is an ancestor of child (i.e., if this item is child's parent, or one of child's parent's ancestors).
 boolean isEnabled()
          Returns true if the item is enabled; otherwise, false is returned.
 boolean isObscured()
          Returns true if this item's bounding rect is completely obscured by the opaque shape of any of colliding items above it (i.e., with a higher Z value than this item).
 boolean isObscured(double x, double y, double w, double h)
          This convenience function is equivalent to calling isObscured(QRectF(x, y, w, h)).
 boolean isObscured(QRectF rect)
          Returns true if rect is completely obscured by the opaque shape of any of colliding items above it (i.e., with a higher Z value than this item).
 boolean isObscuredBy(QGraphicsItemInterface item)
          This function is reimplemented for internal reasons.
 boolean isSelected()
          Returns true if this item is selected; otherwise, false is returned.
 boolean isVisible()
          Returns true if the item is visible; otherwise, false is returned.
 java.lang.Object itemChange(QGraphicsItem.GraphicsItemChange change, java.lang.Object value)
          This virtual function is called by QGraphicsItem to notify custom items that some part of the item's state changes.
 void keyPressEvent(QKeyEvent event)
          This event handler, for event event, can be reimplemented to receive key press events for this item.
 void keyReleaseEvent(QKeyEvent event)
          This event handler, for event event, can be reimplemented to receive key release events for this item.
 QPointF mapFromItem(QGraphicsItemInterface item, double x, double y)
          This convenience function is equivalent to calling mapFromItem(item, QPointF(x, y)).
 QPolygonF mapFromItem(QGraphicsItemInterface item, double x, double y, double w, double h)
          This convenience function is equivalent to calling mapFromItem(item, QRectF(x, y, w, h)).
 QPainterPath mapFromItem(QGraphicsItemInterface item, QPainterPath path)
          Maps the path path, which is in item's coordinate system, to this item's coordinate system, and returns the mapped path.
 QPointF mapFromItem(QGraphicsItemInterface item, QPointF point)
          Maps the point point, which is in item's coordinate system, to this item's coordinate system, and returns the mapped coordinate.
 QPolygonF mapFromItem(QGraphicsItemInterface item, QPolygonF polygon)
          Maps the polygon polygon, which is in item's coordinate system, to this item's coordinate system, and returns the mapped polygon.
 QPolygonF mapFromItem(QGraphicsItemInterface item, QRectF rect)
          Maps the rectangle rect, which is in item's coordinate system, to this item's coordinate system, and returns the mapped rectangle as a polygon.
 QPointF mapFromParent(double x, double y)
          This convenience function is equivalent to calling mapFromParent(QPointF(x, y)).
 QPolygonF mapFromParent(double x, double y, double w, double h)
          This convenience function is equivalent to calling mapFromItem(QRectF(x, y, w, h)).
 QPainterPath mapFromParent(QPainterPath path)
          Maps the path path, which is in this item's parent's coordinate system, to this item's coordinate system, and returns the mapped path.
 QPointF mapFromParent(QPointF point)
          Maps the point point, which is in this item's parent's coordinate system, to this item's coordinate system, and returns the mapped coordinate.
 QPolygonF mapFromParent(QPolygonF polygon)
          Maps the polygon polygon, which is in this item's parent's coordinate system, to this item's coordinate system, and returns the mapped polygon.
 QPolygonF mapFromParent(QRectF rect)
          Maps the rectangle rect, which is in this item's parent's coordinate system, to this item's coordinate system, and returns the mapped rectangle as a polygon.
 QPointF mapFromScene(double x, double y)
          This convenience function is equivalent to calling mapFromScene(QPointF(x, y)).
 QPolygonF mapFromScene(double x, double y, double w, double h)
          This convenience function is equivalent to calling mapFromScene(QRectF(x, y, w, h)).
 QPainterPath mapFromScene(QPainterPath path)
          Maps the path path, which is in this item's scene's coordinate system, to this item's coordinate system, and returns the mapped path.
 QPointF mapFromScene(QPointF point)
          Maps the point point, which is in this item's scene's coordinate system, to this item's coordinate system, and returns the mapped coordinate.
 QPolygonF mapFromScene(QPolygonF polygon)
          Maps the polygon polygon, which is in this item's scene's coordinate system, to this item's coordinate system, and returns the mapped polygon.
 QPolygonF mapFromScene(QRectF rect)
          Maps the rectangle rect, which is in this item's scene's coordinate system, to this item's coordinate system, and returns the mapped rectangle as a polygon.
 QPointF mapToItem(QGraphicsItemInterface item, double x, double y)
          This convenience function is equivalent to calling mapToItem(item, QPointF(x, y)).
 QPolygonF mapToItem(QGraphicsItemInterface item, double x, double y, double w, double h)
          This convenience function is equivalent to calling mapToItem(item, QRectF(x, y, w, h)).
 QPainterPath mapToItem(QGraphicsItemInterface item, QPainterPath path)
          Maps the path path, which is in this item's coordinate system, to item's coordinate system, and returns the mapped path.
 QPointF mapToItem(QGraphicsItemInterface item, QPointF point)
          Maps the point point, which is in this item's coordinate system, to item's coordinate system, and returns the mapped coordinate.
 QPolygonF mapToItem(QGraphicsItemInterface item, QPolygonF polygon)
          Maps the polygon polygon, which is in this item's coordinate system, to item's coordinate system, and returns the mapped polygon.
 QPolygonF mapToItem(QGraphicsItemInterface item, QRectF rect)
          Maps the rectangle rect, which is in this item's coordinate system, to item's coordinate system, and returns the mapped rectangle as a polygon.
 QPointF mapToParent(double x, double y)
          This convenience function is equivalent to calling mapToParent(QPointF(x, y)).
 QPolygonF mapToParent(double x, double y, double w, double h)
          This convenience function is equivalent to calling mapToParent(QRectF(x, y, w, h)).
 QPainterPath mapToParent(QPainterPath path)
          Maps the path path, which is in this item's coordinate system, to its parent's coordinate system, and returns the mapped path.
 QPointF mapToParent(QPointF point)
          Maps the point point, which is in this item's coordinate system, to its parent's coordinate system, and returns the mapped coordinate.
 QPolygonF mapToParent(QPolygonF polygon)
          Maps the polygon polygon, which is in this item's coordinate system, to its parent's coordinate system, and returns the mapped polygon.
 QPolygonF mapToParent(QRectF rect)
          Maps the rectangle rect, which is in this item's coordinate system, to its parent's coordinate system, and returns the mapped rectangle as a polygon.
 QPointF mapToScene(double x, double y)
          This convenience function is equivalent to calling mapToScene(QPointF(x, y)).
 QPolygonF mapToScene(double x, double y, double w, double h)
          This convenience function is equivalent to calling mapToScene(QRectF(x, y, w, h)).
 QPainterPath mapToScene(QPainterPath path)
          Maps the path path, which is in this item's coordinate system, to the scene's coordinate system, and returns the mapped path.
 QPointF mapToScene(QPointF point)
          Maps the point point, which is in this item's coordinate system, to the scene's coordinate system, and returns the mapped coordinate.
 QPolygonF mapToScene(QPolygonF polygon)
          Maps the polygon polygon, which is in this item's coordinate system, to the scene's coordinate system, and returns the mapped polygon.
 QPolygonF mapToScene(QRectF rect)
          Maps the rectangle rect, which is in this item's coordinate system, to the scene's coordinate system, and returns the mapped rectangle as a polygon.
 void mouseDoubleClickEvent(QGraphicsSceneMouseEvent event)
          This event handler, for event event, can be reimplemented to receive mouse doubleclick events for this item.
 void mouseMoveEvent(QGraphicsSceneMouseEvent event)
          This event handler, for event event, can be reimplemented to receive mouse move events for this item.
 void mousePressEvent(QGraphicsSceneMouseEvent event)
          This event handler, for event event, can be reimplemented to receive mouse press events for this item.
 void mouseReleaseEvent(QGraphicsSceneMouseEvent event)
          This event handler, for event event, can be reimplemented to receive mouse release events for this item.
 void moveBy(double dx, double dy)
          Moves the item by dx points horizontally, and dy point vertically.
 QPainterPath opaqueArea()
          This function is reimplemented for internal reasons.
abstract  void paint(QPainter painter, QStyleOptionGraphicsItem option, QWidget widget)
          This function, which is usually called by QGraphicsView, paints the contents of an item in local coordinates.
 QGraphicsItemInterface parentItem()
          Returns a pointer to this item's parent item.
 QPen pen()
          Returns the item's pen.
 QPointF pos()
          Returns the position of the item in parent coordinates.
 void prepareGeometryChange()
          Prepares the item for a geometry change.
 void removeFromIndex()
          
 void removeSceneEventFilter(QGraphicsItemInterface filterItem)
          Removes an event filter on this item from filterItem.
 void resetTransform()
          Resets this item's transformation matrix to the identity matrix.
 void rotate(double angle)
          Rotates the current item transformation angle degrees clockwise around its origin.
 void scale(double sx, double sy)
          Scales the current item transformation by (sx, sy) around its origin.
 QGraphicsScene scene()
          Returns the current scene for the item, or 0 if the item is not stored in a scene.
 QRectF sceneBoundingRect()
          Returns the bounding rect of this item in scene coordinates, by combining sceneTransform with boundingRect.
 boolean sceneEvent(QEvent event)
          This virtual function receives events to this item.
 boolean sceneEventFilter(QGraphicsItemInterface watched, QEvent event)
          Filters events for the item watched.
 QPointF scenePos()
          Returns the item's position in scene coordinates.
 QTransform sceneTransform()
          Returns this item's scene transformation matrix.
 void setAcceptDrops(boolean on)
          If on is true, this item will accept drag and drop events; otherwise, it is transparent for drag and drop events.
 void setAcceptedMouseButtons(Qt.MouseButtons buttons)
          Sets the mouse buttons that this item accepts mouse events for.
 void setAcceptsHoverEvents(boolean enabled)
          If enabled is true, this item will accept hover events; otherwise, it will ignore them.
 void setBrush(QBrush brush)
          Sets the item's brush to brush.
 void setCursor(QCursor cursor)
          Sets the current cursor shape for the item to cursor.
 void setData(int key, java.lang.Object value)
          Sets this item's custom data for the key key to value.
 void setEnabled(boolean enabled)
          If enabled is true, the item is enabled; otherwise, it is disabled.
 void setExtension(QGraphicsItem.Extension extension, java.lang.Object variant)
          
 void setFlag(QGraphicsItem.GraphicsItemFlag flag, boolean enabled)
          If enabled is true, the item flag flag is enabled; otherwise, it is disabled.
 void setFlags(QGraphicsItem.GraphicsItemFlags flags)
          Sets the item flags to flags.
 void setFocus(Qt.FocusReason focusReason)
          Gives keyboard input focus to this item.
 void setGroup(QGraphicsItemGroup group)
          Adds this item to the item group group.
 void setHandlesChildEvents(boolean enabled)
          If enabled is true, this item is set to handle all events for all its children (i.e., all events intented for any of its children are instead sent to this item); otherwise, if enabled is false, this item will only handle its own events.
 void setParentItem(QGraphicsItemInterface parent)
          Sets this item's parent item to parent.
 void setPen(QPen pen)
          Sets the pen for this item to pen.
 void setPos(double x, double y)
          This convenience function is equivalent to calling setPos(QPointF(x, y)).
 void setPos(QPointF pos)
          Sets the position of the item to pos, which is in parent coordinates.
 void setSelected(boolean selected)
          If selected is true and this item is selectable, this item is selected; otherwise, it is unselected.
 void setToolTip(java.lang.String toolTip)
          Sets the item's tool tip to toolTip.
 void setTransform(QTransform matrix, boolean combine)
          Sets the item's current transformation matrix to matrix.
 void setVisible(boolean visible)
          If visible is true, the item is made visible.
 void setZValue(double z)
          Sets the Z-value, or the elevation, of the item, to z.
 QPainterPath shape()
          Returns the shape of this item as a QPainterPath in local coordinates.
 void shear(double sh, double sv)
          Shears the current item transformation by (sh, sv).
 void show()
          Shows the item.
 boolean supportsExtension(QGraphicsItem.Extension extension)
          
 java.lang.String toolTip()
          Returns the item's tool tip, or an empty QString if no tool tip has been set.
 QGraphicsItemInterface topLevelItem()
          Returns this item's top-level item.
 QTransform transform()
          Returns this item's transformation matrix.
 void translate(double dx, double dy)
          Translates the current item transformation by (dx, dy).
 int type()
          Returns the type of an item as an int.
 void unsetCursor()
          Clears the cursor from this item.
 void update(double x, double y, double width, double height)
          This convenience function is equivalent to calling update(QRectF(x, y, width, height)).
 void update(QRectF rect)
          Schedules a redraw of the area covered by rect in this item.
 void wheelEvent(QGraphicsSceneWheelEvent event)
          This event handler, for event event, can be reimplemented to receive wheel events for this item.
 double x()
          This convenience function is equivalent to calling pos.x.
 double y()
          This convenience function is equivalent to calling pos.y.
 double zValue()
          Returns the Z-value, or the elevation, of the item.
 
Methods inherited from class com.trolltech.qt.QtJambiObject
dispose, disposed, finalize, reassignNativeResources, tr, tr, tr
 
Methods inherited from class com.trolltech.qt.QSignalEmitter
blockSignals, disconnect, disconnect, signalsBlocked, signalSender, thread
 
Methods inherited from class java.lang.Object
clone, equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 
Methods inherited from interface com.trolltech.qt.QtJambiInterface
disableGarbageCollection, nativeId, nativePointer, reenableGarbageCollection, setJavaOwnership
 

Constructor Detail

QAbstractGraphicsShapeItem

public QAbstractGraphicsShapeItem(QGraphicsItemInterface parent)
Constructs a QAbstractGraphicsShapeItem. parent is passed to QGraphicsItem's constructor.


QAbstractGraphicsShapeItem

public QAbstractGraphicsShapeItem()
Constructs a parentless QAbstractGraphicsShapeItem.


QAbstractGraphicsShapeItem

public QAbstractGraphicsShapeItem(QGraphicsItemInterface parent,
                                  QGraphicsScene scene)
Constructs a new QAbstractGraphicsShapeItem with the specified parent and adds it to scene.

Method Detail

acceptDrops

public final boolean acceptDrops()

Returns true if this item can accept drag and drop events; otherwise, returns false. By default, items do not accept drag and drop events; items are transparent to drag and drop.

Specified by:
acceptDrops in interface QGraphicsItemInterface
See Also:
setAcceptDrops

acceptedMouseButtons

public final Qt.MouseButtons acceptedMouseButtons()

Returns the mouse buttons that this item accepts mouse events for. By default, all mouse buttons are accepted.

If an item accepts a mouse button, it will become the mouse grabber item when a mouse press event is delivered for that mouse button. However, if the item does not accept the button, QGraphicsScene will forward the mouse events to the first item beneath it that does.

Specified by:
acceptedMouseButtons in interface QGraphicsItemInterface
See Also:
setAcceptedMouseButtons, mousePressEvent

acceptsHoverEvents

public final boolean acceptsHoverEvents()

Returns true if an item accepts hover events (QGraphicsSceneHoverEvent); otherwise, returns false. By default, items do not accept hover events.

Specified by:
acceptsHoverEvents in interface QGraphicsItemInterface
See Also:
setAcceptsHoverEvents, setAcceptedMouseButtons

addToIndex

public final void addToIndex()

Specified by:
addToIndex in interface QGraphicsItemInterface

brush

public final QBrush brush()

Returns the item's brush, or an empty brush if no brush has been set.

See Also:
setBrush

childItems

public final java.util.List<QGraphicsItemInterface> childItems()

Returns a list of this item's children. The items are returned in no particular order.

Specified by:
childItems in interface QGraphicsItemInterface
See Also:
setParentItem

childrenBoundingRect

public final QRectF childrenBoundingRect()

Returns the bounding rect of this item's descendents (i.e., its children, their children, etc.) in local coordinates. If the item has no children, this function returns an empty QRectF.

This does not include this item's own bounding rect; it only returns its descendents' accumulated bounding rect. If you need to include this item's bounding rect, you can add boundingRect to childrenBoundingRect using QRectF::operator|().

This function is linear in complexity; it determines the size of the returned bounding rect by iterating through all descendents.

Specified by:
childrenBoundingRect in interface QGraphicsItemInterface
See Also:
boundingRect, sceneBoundingRect

clearFocus

public final void clearFocus()

Takes keyboard input focus from the item.

If it has focus, a focus out event is sent to this item to tell it that it is about to lose the focus.

Only items that set the ItemIsFocusable flag can accept keyboard focus.

Specified by:
clearFocus in interface QGraphicsItemInterface
See Also:
setFocus

collidingItems

public final java.util.List<QGraphicsItemInterface> collidingItems(Qt.ItemSelectionMode mode)

Returns a list of all items that collide with this item.

The way collisions are detected is determined by mode. The default value for mode is Qt::IntersectsItemShape; All items whose shape intersects or is contained by this item's shape are returned.

Specified by:
collidingItems in interface QGraphicsItemInterface
See Also:
QGraphicsScene::collidingItems, collidesWithItem

cursor

public final QCursor cursor()

Returns the current cursor shape for the item. The mouse cursor will assume this shape when it's over this item. See the list of predefined cursor objects for a range of useful shapes.

An editor item might want to use an I-beam cursor:

    item->setCursor(Qt::IBeamCursor);

If no cursor has been set, the parent's cursor is used.

Specified by:
cursor in interface QGraphicsItemInterface
See Also:
setCursor, hasCursor, unsetCursor, QWidget::cursor, QApplication::overrideCursor

data

public final java.lang.Object data(int key)

Returns this item's custom data for the key key as a QVariant.

Custom item data is useful for storing arbitrary properties in any item. Example:

    static const int ObjectName = 0;

    QGraphicsItem *item = scene.itemAt(100, 50);
    if (item->data(ObjectName).toString().isEmpty()) {
        if (qgraphicsitem_cast<ButtonItem *>(item))
            item->setData(ObjectName, "Button");
    }

Qt does not use this feature for storing data; it is provided solely for the convenience of the user.

Specified by:
data in interface QGraphicsItemInterface
See Also:
setData

deviceTransform

public final QTransform deviceTransform(QTransform viewportTransform)

Returns this item's device transformation matrix, using viewportTransform to map from scene to device coordinates. This matrix can be used to map coordinates and geometrical shapes from this item's local coordinate system to the viewport's (or any device's) coordinate system. To map coordinates from the viewport, you must first invert the returned matrix.

Example:

    QGraphicsRectItem rect;
    rect.setPos(100, 100);

    rect.deviceTransform(view->viewportTransform()).map(QPointF(0, 0));
    // returns the item's (0, 0) point in view's viewport coordinates

    rect.deviceTransform(view->viewportTransform()).inverted().map(QPointF(100, 100));
    // returns view's viewport's (100, 100) coordinate in item coordinates

This function is the same as combining this item's scene transform with the view's viewport transform, but is also understands ItemIgnoresTransformations.

Specified by:
deviceTransform in interface QGraphicsItemInterface
See Also:
transform, setTransform, scenePos, The Graphics View Coordinate System

ensureVisible

public final void ensureVisible(double x,
                                double y,
                                double w,
                                double h,
                                int xmargin,
                                int ymargin)

This convenience function is equivalent to calling ensureVisible(QRectF(x, y, w, h), xmargin, ymargin):

Specified by:
ensureVisible in interface QGraphicsItemInterface

ensureVisible

public final void ensureVisible(QRectF rect,
                                int xmargin,
                                int ymargin)

If this item is part of a scene that is viewed by a QGraphicsView, this convenience function will attempt to scroll the view to ensure that rect is visible inside the view's viewport. If rect is a null rect (the default), QGraphicsItem will default to the item's bounding rect. xmargin and ymargin are the number of pixels the view should use for margins.

If the specified rect cannot be reached, the contents are scrolled to the nearest valid position.

If this item is not viewed by a QGraphicsView, this function does nothing.

Specified by:
ensureVisible in interface QGraphicsItemInterface
See Also:
QGraphicsView::ensureVisible

flags

public final QGraphicsItem.GraphicsItemFlags flags()

Returns this item's flags. The flags describe what configurable features of the item are enabled and not. For example, if the flags include ItemIsFocusable, the item can accept input focus.

By default, no flags are enabled.

Specified by:
flags in interface QGraphicsItemInterface
See Also:
setFlags, setFlag

group

public final QGraphicsItemGroup group()

Returns a pointer to this item's item group, or 0 if this item is not member of a group.

Specified by:
group in interface QGraphicsItemInterface
See Also:
setGroup, QGraphicsItemGroup, QGraphicsScene::createItemGroup

handlesChildEvents

public final boolean handlesChildEvents()

Returns true if this item handles child events (i.e., all events intended for any of its children are instead sent to this item); otherwise, false is returned.

This property is useful for item groups; it allows one item to handle events on behalf of its children, as opposed to its children handling their events individually.

The default is to return false; children handle their own events. The exception for this is if the item is a QGraphicsItemGroup, then it defaults to return true.

Specified by:
handlesChildEvents in interface QGraphicsItemInterface
See Also:
setHandlesChildEvents

hasCursor

public final boolean hasCursor()

Returns true if this item has a cursor set; otherwise, false is returned.

By default, items don't have any cursor set. cursor will return a standard pointing arrow cursor.

Specified by:
hasCursor in interface QGraphicsItemInterface
See Also:
unsetCursor

hasFocus

public final boolean hasFocus()

Returns true if this item has focus (i.e., can accept key events); otherwise, returns false.

Specified by:
hasFocus in interface QGraphicsItemInterface
See Also:
setFocus, QGraphicsScene::setFocusItem

hide

public final void hide()

Hides the item. (Items are visible by default.)

This convenience function is equivalent to calling setVisible(false).

Specified by:
hide in interface QGraphicsItemInterface
See Also:
show, setVisible

installSceneEventFilter

public final void installSceneEventFilter(QGraphicsItemInterface filterItem)

Installs an event filter for this item on filterItem, causing all events for this item to first pass through filterItem's sceneEventFilter function.

To filter another item's events, install this item as an event filter for the other item. Example:

    QGraphicsScene scene;
    QGraphicsEllipseItem *ellipse = scene.addEllipse(QRectF(-10, -10, 20, 20));
    QGraphicsLineItem *line = scene.addLine(QLineF(-10, -10, 20, 20));

    line->installSceneEventFilter(ellipse);
    // line's events are filtered by ellipse's sceneEventFilter() function.

    ellipse->installSceneEventFilter(line);
    // ellipse's events are filtered by line's sceneEventFilter() function.

An item can only filter events for other items in the same scene. Also, an item cannot filter its own events; instead, you can reimplement sceneEvent directly.

Specified by:
installSceneEventFilter in interface QGraphicsItemInterface
See Also:
removeSceneEventFilter, sceneEventFilter, sceneEvent

isAncestorOf

public final boolean isAncestorOf(QGraphicsItemInterface child)

Returns true if this item is an ancestor of child (i.e., if this item is child's parent, or one of child's parent's ancestors).

Specified by:
isAncestorOf in interface QGraphicsItemInterface
See Also:
parentItem

isEnabled

public final boolean isEnabled()

Returns true if the item is enabled; otherwise, false is returned.

Specified by:
isEnabled in interface QGraphicsItemInterface
See Also:
setEnabled

isObscured

public final boolean isObscured()

Returns true if this item's bounding rect is completely obscured by the opaque shape of any of colliding items above it (i.e., with a higher Z value than this item).

Its implementation is based on calling isObscuredBy, which you can reimplement to provide a custom obscurity algorithm.

Specified by:
isObscured in interface QGraphicsItemInterface
See Also:
opaqueArea

isObscured

public final boolean isObscured(double x,
                                double y,
                                double w,
                                double h)

This convenience function is equivalent to calling isObscured(QRectF(x, y, w, h)).

Specified by:
isObscured in interface QGraphicsItemInterface

isObscured

public final boolean isObscured(QRectF rect)

Returns true if rect is completely obscured by the opaque shape of any of colliding items above it (i.e., with a higher Z value than this item).

Unlike the default isObscured function, this function does not call isObscuredBy.

Specified by:
isObscured in interface QGraphicsItemInterface
See Also:
opaqueArea

isSelected

public final boolean isSelected()

Returns true if this item is selected; otherwise, false is returned.

Items that are in a group inherit the group's selected state.

Items are not selected by default.

Specified by:
isSelected in interface QGraphicsItemInterface
See Also:
setSelected, QGraphicsScene::setSelectionArea

isVisible

public final boolean isVisible()

Returns true if the item is visible; otherwise, false is returned.

Note that the item's general visibility is unrelated to whether or not it is actually being visualized by a QGraphicsView.

Specified by:
isVisible in interface QGraphicsItemInterface
See Also:
setVisible

mapFromItem

public final QPainterPath mapFromItem(QGraphicsItemInterface item,
                                      QPainterPath path)

Maps the path path, which is in item's coordinate system, to this item's coordinate system, and returns the mapped path.

If item is 0, this function returns the same as mapFromScene.

Specified by:
mapFromItem in interface QGraphicsItemInterface
See Also:
mapFromParent, mapFromScene, mapToItem, The Graphics View Coordinate System

mapFromItem

public final QPolygonF mapFromItem(QGraphicsItemInterface item,
                                   QPolygonF polygon)

Maps the polygon polygon, which is in item's coordinate system, to this item's coordinate system, and returns the mapped polygon.

If item is 0, this function returns the same as mapFromScene.

Specified by:
mapFromItem in interface QGraphicsItemInterface
See Also:
mapToItem, mapFromParent, transform, The Graphics View Coordinate System

mapFromItem

public final QPolygonF mapFromItem(QGraphicsItemInterface item,
                                   QRectF rect)

Maps the rectangle rect, which is in item's coordinate system, to this item's coordinate system, and returns the mapped rectangle as a polygon.

If item is 0, this function returns the same as mapFromScene

Specified by:
mapFromItem in interface QGraphicsItemInterface
See Also:
mapToItem, mapFromParent, transform, The Graphics View Coordinate System

mapFromItem

public final QPolygonF mapFromItem(QGraphicsItemInterface item,
                                   double x,
                                   double y,
                                   double w,
                                   double h)

This convenience function is equivalent to calling mapFromItem(item, QRectF(x, y, w, h)).

Specified by:
mapFromItem in interface QGraphicsItemInterface

mapFromItem

public final QPointF mapFromItem(QGraphicsItemInterface item,
                                 double x,
                                 double y)

This convenience function is equivalent to calling mapFromItem(item, QPointF(x, y)).

Specified by:
mapFromItem in interface QGraphicsItemInterface

mapFromItem

public final QPointF mapFromItem(QGraphicsItemInterface item,
                                 QPointF point)

Maps the point point, which is in item's coordinate system, to this item's coordinate system, and returns the mapped coordinate.

If item is 0, this function returns the same as mapFromScene.

Specified by:
mapFromItem in interface QGraphicsItemInterface
See Also:
mapFromParent, mapFromScene, transform, mapToItem, The Graphics View Coordinate System

mapFromParent

public final QPainterPath mapFromParent(QPainterPath path)

Maps the path path, which is in this item's parent's coordinate system, to this item's coordinate system, and returns the mapped path.

Specified by:
mapFromParent in interface QGraphicsItemInterface
See Also:
mapFromScene, mapFromItem, mapToParent, The Graphics View Coordinate System

mapFromParent

public final QPointF mapFromParent(double x,
                                   double y)

This convenience function is equivalent to calling mapFromParent(QPointF(x, y)).

Specified by:
mapFromParent in interface QGraphicsItemInterface

mapFromParent

public final QPolygonF mapFromParent(QPolygonF polygon)

Maps the polygon polygon, which is in this item's parent's coordinate system, to this item's coordinate system, and returns the mapped polygon.

Specified by:
mapFromParent in interface QGraphicsItemInterface
See Also:
mapToParent, mapToItem, transform, The Graphics View Coordinate System

mapFromParent

public final QPointF mapFromParent(QPointF point)

Maps the point point, which is in this item's parent's coordinate system, to this item's coordinate system, and returns the mapped coordinate.

Specified by:
mapFromParent in interface QGraphicsItemInterface
See Also:
mapFromItem, mapFromScene, transform, mapToParent, The Graphics View Coordinate System

mapFromParent

public final QPolygonF mapFromParent(QRectF rect)

Maps the rectangle rect, which is in this item's parent's coordinate system, to this item's coordinate system, and returns the mapped rectangle as a polygon.

Specified by:
mapFromParent in interface QGraphicsItemInterface
See Also:
mapToParent, mapFromItem, transform, The Graphics View Coordinate System

mapFromParent

public final QPolygonF mapFromParent(double x,
                                     double y,
                                     double w,
                                     double h)

This convenience function is equivalent to calling mapFromItem(QRectF(x, y, w, h)).

Specified by:
mapFromParent in interface QGraphicsItemInterface

mapFromScene

public final QPointF mapFromScene(double x,
                                  double y)

This convenience function is equivalent to calling mapFromScene(QPointF(x, y)).

Specified by:
mapFromScene in interface QGraphicsItemInterface

mapFromScene

public final QPointF mapFromScene(QPointF point)

Maps the point point, which is in this item's scene's coordinate system, to this item's coordinate system, and returns the mapped coordinate.

Specified by:
mapFromScene in interface QGraphicsItemInterface
See Also:
mapFromItem, mapFromParent, transform, mapToScene, The Graphics View Coordinate System

mapFromScene

public final QPolygonF mapFromScene(double x,
                                    double y,
                                    double w,
                                    double h)

This convenience function is equivalent to calling mapFromScene(QRectF(x, y, w, h)).

Specified by:
mapFromScene in interface QGraphicsItemInterface

mapFromScene

public final QPolygonF mapFromScene(QRectF rect)

Maps the rectangle rect, which is in this item's scene's coordinate system, to this item's coordinate system, and returns the mapped rectangle as a polygon.

Specified by:
mapFromScene in interface QGraphicsItemInterface
See Also:
mapToScene, mapFromItem, transform, The Graphics View Coordinate System

mapFromScene

public final QPolygonF mapFromScene(QPolygonF polygon)

Maps the polygon polygon, which is in this item's scene's coordinate system, to this item's coordinate system, and returns the mapped polygon.

Specified by:
mapFromScene in interface QGraphicsItemInterface
See Also:
mapToScene, mapFromParent, transform, The Graphics View Coordinate System

mapFromScene

public final QPainterPath mapFromScene(QPainterPath path)

Maps the path path, which is in this item's scene's coordinate system, to this item's coordinate system, and returns the mapped path.

Specified by:
mapFromScene in interface QGraphicsItemInterface
See Also:
mapFromParent, mapFromItem, mapToScene, The Graphics View Coordinate System

mapToItem

public final QPointF mapToItem(QGraphicsItemInterface item,
                               QPointF point)

Maps the point point, which is in this item's coordinate system, to item's coordinate system, and returns the mapped coordinate.

If item is 0, this function returns the same as mapToScene.

Specified by:
mapToItem in interface QGraphicsItemInterface
See Also:
mapToParent, mapToScene, transform, mapFromItem, The Graphics View Coordinate System

mapToItem

public final QPolygonF mapToItem(QGraphicsItemInterface item,
                                 double x,
                                 double y,
                                 double w,
                                 double h)

This convenience function is equivalent to calling mapToItem(item, QRectF(x, y, w, h)).

Specified by:
mapToItem in interface QGraphicsItemInterface

mapToItem

public final QPolygonF mapToItem(QGraphicsItemInterface item,
                                 QPolygonF polygon)

Maps the polygon polygon, which is in this item's coordinate system, to item's coordinate system, and returns the mapped polygon.

If item is 0, this function returns the same as mapToScene.

Specified by:
mapToItem in interface QGraphicsItemInterface
See Also:
mapToParent, mapToScene, mapFromItem, The Graphics View Coordinate System

mapToItem

public final QPointF mapToItem(QGraphicsItemInterface item,
                               double x,
                               double y)

This convenience function is equivalent to calling mapToItem(item, QPointF(x, y)).

Specified by:
mapToItem in interface QGraphicsItemInterface

mapToItem

public final QPolygonF mapToItem(QGraphicsItemInterface item,
                                 QRectF rect)

Maps the rectangle rect, which is in this item's coordinate system, to item's coordinate system, and returns the mapped rectangle as a polygon.

If item is 0, this function returns the same as mapToScene.

Specified by:
mapToItem in interface QGraphicsItemInterface
See Also:
mapToParent, mapToScene, mapFromItem, The Graphics View Coordinate System

mapToItem

public final QPainterPath mapToItem(QGraphicsItemInterface item,
                                    QPainterPath path)

Maps the path path, which is in this item's coordinate system, to item's coordinate system, and returns the mapped path.

If item is 0, this function returns the same as mapToScene.

Specified by:
mapToItem in interface QGraphicsItemInterface
See Also:
mapToParent, mapToScene, mapFromItem, The Graphics View Coordinate System

mapToParent

public final QPolygonF mapToParent(double x,
                                   double y,
                                   double w,
                                   double h)

This convenience function is equivalent to calling mapToParent(QRectF(x, y, w, h)).

Specified by:
mapToParent in interface QGraphicsItemInterface

mapToParent

public final QPointF mapToParent(double x,
                                 double y)

This convenience function is equivalent to calling mapToParent(QPointF(x, y)).

Specified by:
mapToParent in interface QGraphicsItemInterface

mapToParent

public final QPointF mapToParent(QPointF point)

Maps the point point, which is in this item's coordinate system, to its parent's coordinate system, and returns the mapped coordinate. If the item has no parent, point will be mapped to the scene's coordinate system.

Specified by:
mapToParent in interface QGraphicsItemInterface
See Also:
mapToItem, mapToScene, transform, mapFromParent, The Graphics View Coordinate System

mapToParent

public final QPainterPath mapToParent(QPainterPath path)

Maps the path path, which is in this item's coordinate system, to its parent's coordinate system, and returns the mapped path. If the item has no parent, path will be mapped to the scene's coordinate system.

Specified by:
mapToParent in interface QGraphicsItemInterface
See Also:
mapToScene, mapToItem, mapFromParent, The Graphics View Coordinate System

mapToParent

public final QPolygonF mapToParent(QRectF rect)

Maps the rectangle rect, which is in this item's coordinate system, to its parent's coordinate system, and returns the mapped rectangle as a polygon. If the item has no parent, rect will be mapped to the scene's coordinate system.

Specified by:
mapToParent in interface QGraphicsItemInterface
See Also:
mapToScene, mapToItem, mapFromParent, The Graphics View Coordinate System

mapToParent

public final QPolygonF mapToParent(QPolygonF polygon)

Maps the polygon polygon, which is in this item's coordinate system, to its parent's coordinate system, and returns the mapped polygon. If the item has no parent, polygon will be mapped to the scene's coordinate system.

Specified by:
mapToParent in interface QGraphicsItemInterface
See Also:
mapToScene, mapToItem, mapFromParent, The Graphics View Coordinate System

mapToScene

public final QPolygonF mapToScene(QRectF rect)

Maps the rectangle rect, which is in this item's coordinate system, to the scene's coordinate system, and returns the mapped rectangle as a polygon.

Specified by:
mapToScene in interface QGraphicsItemInterface
See Also:
mapToParent, mapToItem, mapFromScene, The Graphics View Coordinate System

mapToScene

public final QPainterPath mapToScene(QPainterPath path)

Maps the path path, which is in this item's coordinate system, to the scene's coordinate system, and returns the mapped path.

Specified by:
mapToScene in interface QGraphicsItemInterface
See Also:
mapToParent, mapToItem, mapFromScene, The Graphics View Coordinate System

mapToScene

public final QPolygonF mapToScene(QPolygonF polygon)

Maps the polygon polygon, which is in this item's coordinate system, to the scene's coordinate system, and returns the mapped polygon.

Specified by:
mapToScene in interface QGraphicsItemInterface
See Also:
mapToParent, mapToItem, mapFromScene, The Graphics View Coordinate System

mapToScene

public final QPolygonF mapToScene(double x,
                                  double y,
                                  double w,
                                  double h)

This convenience function is equivalent to calling mapToScene(QRectF(x, y, w, h)).

Specified by:
mapToScene in interface QGraphicsItemInterface

mapToScene

public final QPointF mapToScene(double x,
                                double y)

This convenience function is equivalent to calling mapToScene(QPointF(x, y)).

Specified by:
mapToScene in interface QGraphicsItemInterface

mapToScene

public final QPointF mapToScene(QPointF point)

Maps the point point, which is in this item's coordinate system, to the scene's coordinate system, and returns the mapped coordinate.

Specified by:
mapToScene in interface QGraphicsItemInterface
See Also:
mapToItem, mapToParent, transform, mapFromScene, The Graphics View Coordinate System

moveBy

public final void moveBy(double dx,
                         double dy)

Moves the item by dx points horizontally, and dy point vertically. This function is equivalent to calling setPos(pos + QPointF(dx, dy)).

Specified by:
moveBy in interface QGraphicsItemInterface

parentItem

public final QGraphicsItemInterface parentItem()

Returns a pointer to this item's parent item. If this item does not have a parent, 0 is returned.

Specified by:
parentItem in interface QGraphicsItemInterface
See Also:
setParentItem, children

pen

public final QPen pen()

Returns the item's pen. If no pen has been set, this function returns QPen(), a default black solid line pen with 0 width.

See Also:
setPen

pos

public final QPointF pos()

Returns the position of the item in parent coordinates. If the item has no parent, its position is given in scene coordinates.

The position of the item describes its origin (local coordinate (0, 0)) in parent coordinates; this function returns the same as mapToParent(0, 0).

For convenience, you can also call scenePos to determine the item's position in scene coordinates, regardless of its parent.

Specified by:
pos in interface QGraphicsItemInterface
See Also:
x, y, setPos, matrix, The Graphics View Coordinate System

prepareGeometryChange

public final void prepareGeometryChange()

Prepares the item for a geometry change. Call this function before changing the bounding rect of an item to keep QGraphicsScene's index up to date.

prepareGeometryChange will call update if this is necessary.

Example:

    void CircleItem::setRadius(qreal newRadius)
    {
        if (radius != newRadius) {
            prepareGeometryChange();
            radius = newRadius;
        }
    }

Specified by:
prepareGeometryChange in interface QGraphicsItemInterface
See Also:
boundingRect

removeFromIndex

public final void removeFromIndex()

Specified by:
removeFromIndex in interface QGraphicsItemInterface

removeSceneEventFilter

public final void removeSceneEventFilter(QGraphicsItemInterface filterItem)

Removes an event filter on this item from filterItem.

Specified by:
removeSceneEventFilter in interface QGraphicsItemInterface
See Also:
installSceneEventFilter

resetTransform

public final void resetTransform()

Resets this item's transformation matrix to the identity matrix. This is equivalent to calling setTransform(QTransform()).

Specified by:
resetTransform in interface QGraphicsItemInterface
See Also:
setTransform, transform

rotate

public final void rotate(double angle)

Rotates the current item transformation angle degrees clockwise around its origin. To translate around an arbitrary point (x, y), you need to combine translation and rotation with setTransform.

Example:

    // Rotate an item 45 degrees around (0, 0).
    item->rotate(45);

    // Rotate an item 45 degrees around (x, y).
    item->setTransform(QTransform().translate(x, y).rotate(45).translate(-x, -y));

Specified by:
rotate in interface QGraphicsItemInterface
See Also:
setTransform, transform, scale, shear, translate

scale

public final void scale(double sx,
                        double sy)

Scales the current item transformation by (sx, sy) around its origin. To scale from an arbitrary point (x, y), you need to combine translation and scaling with setTransform.

Example:

    // Scale an item by 3x2 from its origin
    item->scale(3, 2);

    // Scale an item by 3x2 from (x, y)
    item->setTransform(QTransform().translate(x, y).scale(3, 2).translate(-x, -y));

Specified by:
scale in interface QGraphicsItemInterface
See Also:
setTransform, transform, rotate, shear, translate

scene

public final QGraphicsScene scene()

Returns the current scene for the item, or 0 if the item is not stored in a scene.

To add or move an item to a scene, call QGraphicsScene::addItem().

Specified by:
scene in interface QGraphicsItemInterface

sceneBoundingRect

public final QRectF sceneBoundingRect()

Returns the bounding rect of this item in scene coordinates, by combining sceneTransform with boundingRect.

Specified by:
sceneBoundingRect in interface QGraphicsItemInterface
See Also:
boundingRect, The Graphics View Coordinate System

scenePos

public final QPointF scenePos()

Returns the item's position in scene coordinates. This is equivalent to calling mapToScene(0, 0).

Specified by:
scenePos in interface QGraphicsItemInterface
See Also:
pos, sceneTransform, The Graphics View Coordinate System

sceneTransform

public final QTransform sceneTransform()

Returns this item's scene transformation matrix. This matrix can be used to map coordinates and geometrical shapes from this item's local coordinate system to the scene's coordinate system. To map coordinates from the scene, you must first invert the returned matrix.

Example:

    QGraphicsRectItem rect;
    rect.setPos(100, 100);

    rect.sceneTransform().map(QPointF(0, 0));
    // returns QPointF(100, 100);

    rect.sceneTransform().inverted().map(QPointF(100, 100));
    // returns QPointF(0, 0);

Unlike transform, which returns only an item's local transformation, this function includes the item's (and any parents') position.

Specified by:
sceneTransform in interface QGraphicsItemInterface
See Also:
transform, setTransform, scenePos, The Graphics View Coordinate System

setAcceptDrops

public final void setAcceptDrops(boolean on)

If on is true, this item will accept drag and drop events; otherwise, it is transparent for drag and drop events. By default, items do not accept drag and drop events.

Specified by:
setAcceptDrops in interface QGraphicsItemInterface
See Also:
acceptDrops

setAcceptedMouseButtons

public final void setAcceptedMouseButtons(Qt.MouseButtons buttons)

Sets the mouse buttons that this item accepts mouse events for.

By default, all mouse buttons are accepted. If an item accepts a mouse button, it will become the mouse grabber item when a mouse press event is delivered for that button. However, if the item does not accept the mouse button, QGraphicsScene will forward the mouse events to the first item beneath it that does.

To disable mouse events for an item (i.e., make it transparent for mouse events), call setAcceptedMouseButtons(0).

Specified by:
setAcceptedMouseButtons in interface QGraphicsItemInterface
See Also:
acceptedMouseButtons, mousePressEvent

setAcceptsHoverEvents

public final void setAcceptsHoverEvents(boolean enabled)

If enabled is true, this item will accept hover events; otherwise, it will ignore them. By default, items do not accept hover events.

Hover events are delivered when there is no current mouse grabber item. They are sent when the mouse cursor enters an item, when it moves around inside the item, and when the cursor leaves an item. Hover events are commonly used to highlight an item when it's entered, and for tracking the mouse cursor as it hovers over the item (equivalent to QWidget::mouseTracking).

Parent items receive hover enter events before their children, and leave events after their children. The parent does not receive a hover leave event if the cursor enters a child, though; the parent stays "hovered" until the cursor leaves its area, including its children's areas.

If a parent item handles child events (setHandlesChildEvents), it will receive hover move, drag move, and drop events as the cursor passes through its children, but it does not receive hover enter and hover leave, nor drag enter and drag leave events on behalf of its children.

Specified by:
setAcceptsHoverEvents in interface QGraphicsItemInterface
See Also:
acceptsHoverEvents, hoverEnterEvent, hoverMoveEvent, hoverLeaveEvent

setBrush

public final void setBrush(QBrush brush)

Sets the item's brush to brush.

The item's brush is used to fill the item.

If you use a brush with a QGradient, the gradient is relative to the item's coordinate system.

See Also:
brush

setCursor

public final void setCursor(QCursor cursor)

Sets the current cursor shape for the item to cursor. The mouse cursor will assume this shape when it's over this item. See the list of predefined cursor objects for a range of useful shapes.

An editor item might want to use an I-beam cursor:

    item->setCursor(Qt::IBeamCursor);

If no cursor has been set, the cursor of the item beneath is used.

Specified by:
setCursor in interface QGraphicsItemInterface
See Also:
cursor, hasCursor, unsetCursor, QWidget::cursor, QApplication::overrideCursor

setData

public final void setData(int key,
                          java.lang.Object value)

Sets this item's custom data for the key key to value.

Custom item data is useful for storing arbitrary properties for any item. Qt does not use this feature for storing data; it is provided solely for the convenience of the user.

Specified by:
setData in interface QGraphicsItemInterface
See Also:
data

setEnabled

public final void setEnabled(boolean enabled)

If enabled is true, the item is enabled; otherwise, it is disabled.

Disabled items are visible, but they do not receive any events, and cannot take focus nor be selected. Mouse events are discarded; they are not propagated unless the item is also invisible, or if it does not accept mouse events (see acceptedMouseButtons). A disabled item cannot become the mouse grabber, and as a result of this, an item loses the grab if it becomes disabled when grabbing the mouse, just like it loses focus if it had focus when it was disabled.

Disabled items are traditionally drawn using grayed-out colors (see QPalette::Disabled).

If you disable a parent item, all its children will also be disabled. If you enable a parent item, all children will be enabled, unless they have been explicitly disabled (i.e., if you call setEnabled(false) on a child, it will not be reenabled if its parent is disabled, and then enabled again).

Items are enabled by default.

Specified by:
setEnabled in interface QGraphicsItemInterface
See Also:
isEnabled

setFlag

public final void setFlag(QGraphicsItem.GraphicsItemFlag flag,
                          boolean enabled)

If enabled is true, the item flag flag is enabled; otherwise, it is disabled.

Specified by:
setFlag in interface QGraphicsItemInterface
See Also:
flags, setFlags

setFlags

public final void setFlags(QGraphicsItem.GraphicsItemFlags flags)

Sets the item flags to flags. All flags in flags are enabled; all flags not in flags are disabled.

If the item had focus and flags does not enable ItemIsFocusable, the item loses focus as a result of calling this function. Similarly, if the item was selected, and flags does not enabled ItemIsSelectable, the item is automatically unselected.

By default, no flags are enabled.

Specified by:
setFlags in interface QGraphicsItemInterface
See Also:
flags, setFlag

setFocus

public final void setFocus(Qt.FocusReason focusReason)

Gives keyboard input focus to this item. The focusReason argument will be passed into any focus event generated by this function; it is used to give an explanation of what caused the item to get focus.

Only items that set the ItemIsFocusable flag can accept keyboard focus.

If this item is not visible (i.e., isVisible returns false), not enabled, not associated with a scene, or if it already has input focus, this function will do nothing.

As a result of calling this function, this item will receive a focus in event with focusReason. If another item already has focus, that item will first receive a focus out event indicating that it has lost input focus.

Specified by:
setFocus in interface QGraphicsItemInterface
See Also:
clearFocus, hasFocus

setGroup

public final void setGroup(QGraphicsItemGroup group)

Adds this item to the item group group. If group is 0, this item is removed from any current group and added as a child of the previous group's parent.

Specified by:
setGroup in interface QGraphicsItemInterface
See Also:
group, QGraphicsScene::createItemGroup

setHandlesChildEvents

public final void setHandlesChildEvents(boolean enabled)

If enabled is true, this item is set to handle all events for all its children (i.e., all events intented for any of its children are instead sent to this item); otherwise, if enabled is false, this item will only handle its own events. The default value is false.

This property is useful for item groups; it allows one item to handle events on behalf of its children, as opposed to its children handling their events individually.

If a child item accepts hover events, its parent will receive hover move events as the cursor passes through the child, but it does not receive hover enter and hover leave events on behalf of its child.

Specified by:
setHandlesChildEvents in interface QGraphicsItemInterface
See Also:
handlesChildEvents

setParentItem

public final void setParentItem(QGraphicsItemInterface parent)

Sets this item's parent item to parent. If this item already has a parent, it is first removed from the previous parent. If parent is 0, this item will become a top-level item.

Specified by:
setParentItem in interface QGraphicsItemInterface
See Also:
parentItem, children

setPen

public final void setPen(QPen pen)

Sets the pen for this item to pen.

The pen is used to draw the item's outline.

See Also:
pen

setPos

public final void setPos(double x,
                         double y)

This convenience function is equivalent to calling setPos(QPointF(x, y)).

Specified by:
setPos in interface QGraphicsItemInterface
See Also:
pos

setPos

public final void setPos(QPointF pos)

Sets the position of the item to pos, which is in parent coordinates. For items with no parent, pos is in scene coordinates.

The position of the item describes its origin (local coordinate (0, 0)) in parent coordinates.

Specified by:
setPos in interface QGraphicsItemInterface
See Also:
pos, scenePos, The Graphics View Coordinate System

setSelected

public final void setSelected(boolean selected)

If selected is true and this item is selectable, this item is selected; otherwise, it is unselected.

If the item is in a group, the whole group's selected state is toggled by this function. If the group is selected, all items in the group are also selected, and if the group is not selected, no item in the group is selected.

Only visible, enabled, selectable items can be selected. If selected is true and this item is either invisible or disabled or unselectable, this function does nothing.

By default, items cannot be selected. To enable selection, set the ItemIsSelectable flag.

This function is provided for convenience, allowing individual toggling of the selected state of an item. However, a more common way of selecting items is to call QGraphicsScene::setSelectionArea(), which will call this function for all visible, enabled, and selectable items within a specified area on the scene.

Specified by:
setSelected in interface QGraphicsItemInterface
See Also:
isSelected, QGraphicsScene::selectedItems

setToolTip

public final void setToolTip(java.lang.String toolTip)

Sets the item's tool tip to toolTip. If toolTip is empty, the item's tool tip is cleared.

Specified by:
setToolTip in interface QGraphicsItemInterface
See Also:
toolTip, QToolTip

setTransform

public final void setTransform(QTransform matrix,
                               boolean combine)

Sets the item's current transformation matrix to matrix.

If combine is true, then matrix is combined with the current matrix; otherwise, matrix replaces the current matrix. combine is false by default.

To simplify interation with items using a transformed view, QGraphicsItem provides mapTo... and mapFrom... functions that can translate between items' and the scene's coordinates. For example, you can call mapToScene to map an item coordiate to a scene coordinate, or mapFromScene to map from scene coordinates to item coordinates.

Specified by:
setTransform in interface QGraphicsItemInterface
See Also:
transform, rotate, scale, shear, translate, The Graphics View Coordinate System

setVisible

public final void setVisible(boolean visible)

If visible is true, the item is made visible. Otherwise, the item is made invisible. Invisible items are not painted, nor do they receive any events. In particular, mouse events pass right through invisible items, and are delivered to any item that may be behind. Invisible items are also unselectable, they cannot take input focus, and are not detected by QGraphicsScene's item location functions.

If an item becomes invisible while grabbing the mouse, (i.e., while it is receiving mouse events,) it will automatically lose the mouse grab, and the grab is not regained by making the item visible again; it must receive a new mouse press to regain the mouse grab.

Similarly, an invisible item cannot have focus, so if the item has focus when it becomes invisible, it will lose focus, and the focus is not regained by simply making the item visible again.

If you hide a parent item, all its children will also be hidden. If you show a parent item, all children will be shown, unless they have been explicitly hidden (i.e., if you call setVisible(false) on a child, it will not be reshown even if its parent is hidden, and then shown again).

Items are visible by default; it is unnecessary to call setVisible on a new item.

Specified by:
setVisible in interface QGraphicsItemInterface
See Also:
isVisible, show, hide

setZValue

public final void setZValue(double z)

Sets the Z-value, or the elevation, of the item, to z. The elevation decides the stacking order of sibling (neighboring) items. An item of high Z-value will be drawn on top of an item with a lower Z-value if they share the same parent item. In addition, children of an item will always be drawn on top of the parent, regardless of the child's Z-value. Sibling items that share the same Z-value will be drawn in an undefined order, although the order will stay the same for as long as the items live.

Children of different parents are stacked according to the Z-value of each item's ancestor item which is an immediate child of the two items' closest common ancestor. For example, a robot item might define a torso item as the parent of a head item, two arm items, and two upper-leg items. The upper-leg items would each be parents of one lower-leg item, and each lower-leg item would be parents of one foot item. The stacking order of the feet is the same as the stacking order of each foot's ancestor that is an immediate child of the two feet's common ancestor (i.e., the torso item); so the feet are stacked in the same order as the upper-leg items, regardless of each foot's Z-value.

The Z-value does not affect the item's size in any way.

The default Z-value is 0.

Specified by:
setZValue in interface QGraphicsItemInterface
See Also:
zValue

shear

public final void shear(double sh,
                        double sv)

Shears the current item transformation by (sh, sv).

Specified by:
shear in interface QGraphicsItemInterface
See Also:
setTransform, transform, rotate, scale, translate

show

public final void show()

Shows the item. (Items are visible by default.)

This convenience function is equivalent to calling setVisible(true).

Specified by:
show in interface QGraphicsItemInterface
See Also:
hide, setVisible

toolTip

public final java.lang.String toolTip()

Returns the item's tool tip, or an empty QString if no tool tip has been set.

Specified by:
toolTip in interface QGraphicsItemInterface
See Also:
setToolTip, QToolTip

topLevelItem

public final QGraphicsItemInterface topLevelItem()

Returns this item's top-level item. The top-level item is the item's topmost ancestor item whose parent is 0. If an item has no parent, its own pointer is returned (i.e., a top-level item is its own top-level item).

Specified by:
topLevelItem in interface QGraphicsItemInterface
See Also:
parentItem

transform

public final QTransform transform()

Returns this item's transformation matrix. If no matrix has been set, the identity matrix is returned.

Specified by:
transform in interface QGraphicsItemInterface
See Also:
setTransform, sceneTransform

translate

public final void translate(double dx,
                            double dy)

Translates the current item transformation by (dx, dy).

If all you want is to move an item, you should call moveBy or setPos instead; this function changes the item's translation, which is conceptually separate from its position.

Specified by:
translate in interface QGraphicsItemInterface
See Also:
setTransform, transform, rotate, scale, shear

unsetCursor

public final void unsetCursor()

Clears the cursor from this item.

Specified by:
unsetCursor in interface QGraphicsItemInterface
See Also:
hasCursor, setCursor

update

public final void update(QRectF rect)

Schedules a redraw of the area covered by rect in this item. You can call this function whenever your item needs to be redrawn, such as if it changes appearance or size.

This function does not cause an immediate paint; instead it schedules a paint request that is processed by QGraphicsView after control reaches the event loop. The item will only be redrawn if it is visible in any associated view.

As a side effect of the item being repainted, other items that overlap the area rect may also be repainted.

If the item is invisible (i.e., isVisible returns false), this function does nothing.

Specified by:
update in interface QGraphicsItemInterface
See Also:
paint, boundingRect

update

public final void update(double x,
                         double y,
                         double width,
                         double height)

This convenience function is equivalent to calling update(QRectF(x, y, width, height)).

Specified by:
update in interface QGraphicsItemInterface

x

public final double x()

This convenience function is equivalent to calling pos.x.

Specified by:
x in interface QGraphicsItemInterface
See Also:
y

y

public final double y()

This convenience function is equivalent to calling pos.y.

Specified by:
y in interface QGraphicsItemInterface
See Also:
x

zValue

public final double zValue()

Returns the Z-value, or the elevation, of the item. The Z-value decides the stacking order of sibling (neighboring) items.

The default Z-value is 0.

Specified by:
zValue in interface QGraphicsItemInterface
See Also:
setZValue

advance

public void advance(int phase)

This virtual function is called twice for all items by the QGraphicsScene::advance() slot. In the first phase, all items are called with phase == 0, indicating that items on the scene are about to advance, and then all items are called with phase == 1. Reimplement this function to update your item if you need simple scene-controlled animation.

The default implementation does nothing.

For individual item animation, an alternative to this function is to either use QGraphicsItemAnimation, or to multiple-inherit from QObject and QGraphicsItem, and animate your item using QObject::startTimer() and QObject::timerEvent().

Specified by:
advance in interface QGraphicsItemInterface
See Also:
QGraphicsItemAnimation, QTimeLine

boundingRect

public abstract QRectF boundingRect()

This pure virtual function defines the outer bounds of the item as a rectangle; all painting must be restricted to inside an item's bounding rect. QGraphicsView uses this to determine whether the item requires redrawing.

Although the item's shape can be arbitrary, the bounding rect is always rectangular, and it is unaffected by the items' transformation (scale, rotate, etc.).

If you want to change the item's bounding rectangle, you must first call prepareGeometryChange. This notifies the scene of the imminent change, so that its can update its item geometry index; otherwise, the scene will be unaware of the item's new geometry, and the results are undefined (typically, rendering artifacts are left around in the view).

Reimplement this function to let QGraphicsView determine what parts of the widget, if any, need to be redrawn.

Note: For shapes that paint an outline / stroke, it is important to include half the pen width in the bounding rect. It is not necessary to compensate for antialiasing, though.

Example:

    QRectF CircleItem::boundingRect() const
    {
        qreal penWidth = 1;
        return QRectF(-radius - penWidth / 2, -radius - penWidth / 2,
                      diameter + penWidth, diameter + penWidth);
    }

Specified by:
boundingRect in interface QGraphicsItemInterface
See Also:
shape, contains, The Graphics View Coordinate System, prepareGeometryChange

collidesWithItem

public boolean collidesWithItem(QGraphicsItemInterface other,
                                Qt.ItemSelectionMode mode)

Returns true if this item collides with other; otherwise returns false. The ways items collide is determined by mode. The default value for mode is Qt::IntersectsItemShape; other collides with this item if it either intersect or are contained by this item's shape.

The default implementation is based on shape intersection, and it calls shape on both items. Because the complexity of arbitrary shape-shape intersection grows with an order of magnitude when the shapes are complex, this operation can be noticably time consuming. You have the option of reimplementing this function in a subclass of QGraphicsItem to provide a custom algorithm. This allows you to make use of natural constraints in the shapes of your own items, in order to improve the performance of the collision detection. For instance, two untransformed perfectly circular items' collision can be determined very efficiently by comparing their positions and radii.

Keep in mind that when reimplementing this function and calling shape or boundingRect on other, the returned coordinates must be mapped to this item's coordinate system before any intersection can take place.

Specified by:
collidesWithItem in interface QGraphicsItemInterface
See Also:
contains, shape

collidesWithPath

public boolean collidesWithPath(QPainterPath path,
                                Qt.ItemSelectionMode mode)

Returns true if this item collides with path.

The collision is determined by mode. The default value for mode is Qt::IntersectsItemShape; path collides with this item if it either intersects or is contained by this item's shape.

Specified by:
collidesWithPath in interface QGraphicsItemInterface
See Also:
collidesWithItem, contains, shape

contains

public boolean contains(QPointF point)

Returns true if this item contains point, which is in local coordinates; otherwise, false is returned. It is most often called from QGraphicsView to determine what item is under the cursor, and for that reason, the implementation of this function should be as light-weight as possible.

By default, this function calls shape, but you can reimplement it in a subclass to provide a (perhaps more efficient) implementation.

Specified by:
contains in interface QGraphicsItemInterface
See Also:
shape, boundingRect, collidesWithPath

contextMenuEvent

public void contextMenuEvent(QGraphicsSceneContextMenuEvent event)

This event handler can be reimplemented in a subclass to process context menu events. The event parameter contains details about the event to be handled.

If you ignore the event, (i.e., by calling QEvent::ignore(),) event will propagate to any item beneath this item. If no items accept the event, it will be ignored by the scene, and propagate to the view.

It's common to open a QMenu in response to receiving a context menu event. Example:

    void CustomItem::contextMenuEvent(QGraphicsSceneContextMenuEvent *event)
    {
        QMenu menu;
        QAction *removeAction = menu.addAction("Remove");
        QAction *markAction = menu.addAction("Mark");
        QAction *selectedAction = menu.exec(event->screenPos());
        // ...
    }

The default implementation does nothing.

Specified by:
contextMenuEvent in interface QGraphicsItemInterface
See Also:
sceneEvent

dragEnterEvent

public void dragEnterEvent(QGraphicsSceneDragDropEvent event)

This event handler, for event event, can be reimplemented to receive drag enter events for this item. Drag enter events are generated as the cursor enters the item's area.

By accepting the event, (i.e., by calling QEvent::accept(),) the item will accept drop events, in addition to receiving drag move and drag leave. Otherwise, the event will be ignored and propagate to the item beneath. If the event is accepted, the item will receive a drag move event before control goes back to the event loop.

A common implementation of dragEnterEvent accepts or ignores event depending on the associated mime data in event. Example:

    CustomItem::CustomItem()
    {
        setAcceptDrops(true);
        ...
    }

    void CustomItem::dragEnterEvent(QGraphicsSceneDragDropEvent *event)
    {
        event->setAccepted(event->mimeData()->hasFormat("text/plain"));
    }

Items do not receive drag and drop events by default; to enable this feature, call setAcceptDrops(true).

The default implementation does nothing.

Specified by:
dragEnterEvent in interface QGraphicsItemInterface
See Also:
dropEvent, dragMoveEvent, dragLeaveEvent

dragLeaveEvent

public void dragLeaveEvent(QGraphicsSceneDragDropEvent event)

This event handler, for event event, can be reimplemented to receive drag leave events for this item. Drag leave events are generated as the cursor leaves the item's area. Most often you will not need to reimplement this function, but it can be useful for resetting state in your item (e.g., highlighting).

Calling QEvent::ignore() or QEvent::accept() on event has no effect.

Items do not receive drag and drop events by default; to enable this feature, call setAcceptDrops(true).

The default implementation does nothing.

Specified by:
dragLeaveEvent in interface QGraphicsItemInterface
See Also:
dragEnterEvent, dropEvent, dragMoveEvent

dragMoveEvent

public void dragMoveEvent(QGraphicsSceneDragDropEvent event)

This event handler, for event event, can be reimplemented to receive drag move events for this item. Drag move events are generated as the cursor moves around inside the item's area. Most often you will not need to reimplement this function; it is used to indicate that only parts of the item can accept drops.

Calling QEvent::ignore() or QEvent::accept() on event toggles whether or not the item will accept drops at the position from the event. By default, event is accepted, indicating that the item allows drops at the specified position.

Items do not receive drag and drop events by default; to enable this feature, call setAcceptDrops(true).

The default implementation does nothing.

Specified by:
dragMoveEvent in interface QGraphicsItemInterface
See Also:
dropEvent, dragEnterEvent, dragLeaveEvent

dropEvent

public void dropEvent(QGraphicsSceneDragDropEvent event)

This event handler, for event event, can be reimplemented to receive drop events for this item. Items can only receive drop events if the last drag move event was accepted.

Calling QEvent::ignore() or QEvent::accept() on event has no effect.

Items do not receive drag and drop events by default; to enable this feature, call setAcceptDrops(true).

The default implementation does nothing.

Specified by:
dropEvent in interface QGraphicsItemInterface
See Also:
dragEnterEvent, dragMoveEvent, dragLeaveEvent

extension

public java.lang.Object extension(java.lang.Object variant)

Specified by:
extension in interface QGraphicsItemInterface
See Also:
setExtension

focusInEvent

public void focusInEvent(QFocusEvent event)

This event handler, for event event, can be reimplemented to receive focus in events for this item. The default implementation does nothing.

Specified by:
focusInEvent in interface QGraphicsItemInterface
See Also:
focusOutEvent, sceneEvent

focusOutEvent

public void focusOutEvent(QFocusEvent event)

This event handler, for event event, can be reimplemented to receive focus out events for this item. The default implementation does nothing.

Specified by:
focusOutEvent in interface QGraphicsItemInterface
See Also:
focusInEvent, sceneEvent

hoverEnterEvent

public void hoverEnterEvent(QGraphicsSceneHoverEvent event)

This event handler, for event event, can be reimplemented to receive hover enter events for this item. The default implementation calls update; otherwise it does nothing.

Calling QEvent::ignore() or QEvent::accept() on event has no effect.

Specified by:
hoverEnterEvent in interface QGraphicsItemInterface
See Also:
hoverMoveEvent, hoverLeaveEvent, sceneEvent, setAcceptsHoverEvents

hoverLeaveEvent

public void hoverLeaveEvent(QGraphicsSceneHoverEvent event)

This event handler, for event event, can be reimplemented to receive hover leave events for this item. The default implementation calls update; otherwise it does nothing.

Calling QEvent::ignore() or QEvent::accept() on event has no effect.

Specified by:
hoverLeaveEvent in interface QGraphicsItemInterface
See Also:
hoverEnterEvent, hoverMoveEvent, sceneEvent, setAcceptsHoverEvents

hoverMoveEvent

public void hoverMoveEvent(QGraphicsSceneHoverEvent event)

This event handler, for event event, can be reimplemented to receive hover move events for this item. The default implementation does nothing.

Calling QEvent::ignore() or QEvent::accept() on event has no effect.

Specified by:
hoverMoveEvent in interface QGraphicsItemInterface
See Also:
hoverEnterEvent, hoverLeaveEvent, sceneEvent, setAcceptsHoverEvents

inputMethodEvent

public void inputMethodEvent(QInputMethodEvent event)

This event handler, for event event, can be reimplemented to receive input method events for this item. The default implementation ignores the event.

Specified by:
inputMethodEvent in interface QGraphicsItemInterface
See Also:
inputMethodQuery, sceneEvent

inputMethodQuery

public java.lang.Object inputMethodQuery(Qt.InputMethodQuery query)

This method is only relevant for input items. It is used by the input method to query a set of properties of the item to be able to support complex input method operations, such as support for surrounding text and reconversions. query specifies which property is queried.

Specified by:
inputMethodQuery in interface QGraphicsItemInterface
See Also:
inputMethodEvent

isObscuredBy

public boolean isObscuredBy(QGraphicsItemInterface item)

This function is reimplemented for internal reasons.

Specified by:
isObscuredBy in interface QGraphicsItemInterface
See Also:
opaqueArea, isObscured

itemChange

public java.lang.Object itemChange(QGraphicsItem.GraphicsItemChange change,
                                   java.lang.Object value)

This virtual function is called by QGraphicsItem to notify custom items that some part of the item's state changes. By reimplementing this function, your can react to a change, and in some cases, (depending on change,) adjustments can be made.

change is the parameter of the item that is changing. value is the new value; the type of the value depends on change.

Example:

    QVariant Component::itemChange(GraphicsItemChange change, const QVariant &value)
    {
        if (change == ItemPositionChange && scene()) {
            // value is the new position.
            QPointF newPos = value.toPointF();
            QRectF rect = scene()->sceneRect();
            if (!rect.contains(newPos)) {
                // Keep the item inside the scene rect.
                newPos.setX(qMin(rect.right(), qMax(newPos.x(), rect.left())));
                newPos.setY(qMin(rect.bottom(), qMax(newPos.y(), rect.top())));
                return newPos;
            }
        }
        return QGraphicsItem::itemChange(change, value);
    }

The default implementation does nothing, and returns value.

Note: Certain QGraphicsItem functions cannot be called in a reimplementation of this function; see the GraphicsItemChange documentation for details.

Specified by:
itemChange in interface QGraphicsItemInterface
See Also:
GraphicsItemChange

keyPressEvent

public void keyPressEvent(QKeyEvent event)

This event handler, for event event, can be reimplemented to receive key press events for this item. The default implementation ignores the event. If you reimplement this handler, the event will by default be accepted.

Calling QEvent::ignore() or QEvent::accept() on event has no effect.

Note that key events are only received for items that set the ItemIsFocusable flag, and that have keyboard input focus.

Specified by:
keyPressEvent in interface QGraphicsItemInterface
See Also:
keyReleaseEvent, setFocus, QGraphicsScene::setFocusItem, sceneEvent

keyReleaseEvent

public void keyReleaseEvent(QKeyEvent event)

This event handler, for event event, can be reimplemented to receive key release events for this item. The default implementation ignores the event. If you reimplement this handler, the event will by default be accepted.

Calling QEvent::ignore() or QEvent::accept() on event has no effect.

Note that key events are only received for items that set the ItemIsFocusable flag, and that have keyboard input focus.

Specified by:
keyReleaseEvent in interface QGraphicsItemInterface
See Also:
keyPressEvent, setFocus, QGraphicsScene::setFocusItem, sceneEvent

mouseDoubleClickEvent

public void mouseDoubleClickEvent(QGraphicsSceneMouseEvent event)

This event handler, for event event, can be reimplemented to receive mouse doubleclick events for this item.

When doubleclicking an item, the item will first receive a mouse press event, followed by a release event (i.e., a click), then a doubleclick event, and finally a release event.

Calling QEvent::ignore() or QEvent::accept() on event has no effect.

The default implementation calls mousePressEvent. If you want to keep the base implementation when reimplementing this function, call QGraphicsItem::mouseDoubleClickEvent() in your reimplementation.

Specified by:
mouseDoubleClickEvent in interface QGraphicsItemInterface
See Also:
mousePressEvent, mouseMoveEvent, mouseReleaseEvent, sceneEvent

mouseMoveEvent

public void mouseMoveEvent(QGraphicsSceneMouseEvent event)

This event handler, for event event, can be reimplemented to receive mouse move events for this item. If you do receive this event, you can be certain that this item also received a mouse press event, and that this item is the current mouse grabber.

Calling QEvent::ignore() or QEvent::accept() on event has no effect.

The default implementation handles basic item interaction, such as selection and moving. If you want to keep the base implementation when reimplementing this function, call QGraphicsItem::mouseMoveEvent() in your reimplementation.

Specified by:
mouseMoveEvent in interface QGraphicsItemInterface
See Also:
mousePressEvent, mouseReleaseEvent, mouseDoubleClickEvent, sceneEvent

mousePressEvent

public void mousePressEvent(QGraphicsSceneMouseEvent event)

This event handler, for event event, can be reimplemented to receive mouse press events for this item. Mouse press events are only delivered to items that accept the mouse button that is pressed. By default, an item accepts all mouse buttons, but you can change this by calling setAcceptedMouseButtons.

The mouse press event decides which item should become the mouse grabber (see QGraphicsScene::mouseGrabberItem()). If you do not reimplement this function, the press event will propagate to any topmost item beneath this item, and no other mouse events will be delivered to this item.

If you do reimplement this function, event will by default be accepted (see QEvent::accept()), and this item is then the mouse grabber. This allows the item to receive future move, release and doubleclick events. If you call QEvent::ignore() on event, this item will lose the mouse grab, and event will propagate to any topmost item beneath. No further mouse events will be delivered to this item unless a new mouse press event is received.

The default implementation handles basic item interaction, such as selection and moving. If you want to keep the base implementation when reimplementing this function, call QGraphicsItem::mousePressEvent() in your reimplementation.

Specified by:
mousePressEvent in interface QGraphicsItemInterface
See Also:
mouseMoveEvent, mouseReleaseEvent, mouseDoubleClickEvent, sceneEvent

mouseReleaseEvent

public void mouseReleaseEvent(QGraphicsSceneMouseEvent event)

This event handler, for event event, can be reimplemented to receive mouse release events for this item.

Calling QEvent::ignore() or QEvent::accept() on event has no effect.

The default implementation handles basic item interaction, such as selection and moving. If you want to keep the base implementation when reimplementing this function, call QGraphicsItem::mouseReleaseEvent() in your reimplementation.

Specified by:
mouseReleaseEvent in interface QGraphicsItemInterface
See Also:
mousePressEvent, mouseMoveEvent, mouseDoubleClickEvent, sceneEvent

opaqueArea

public QPainterPath opaqueArea()

This function is reimplemented for internal reasons.

Specified by:
opaqueArea in interface QGraphicsItemInterface
See Also:
isObscuredBy, isObscured, shape

paint

public abstract void paint(QPainter painter,
                           QStyleOptionGraphicsItem option,
                           QWidget widget)

This function, which is usually called by QGraphicsView, paints the contents of an item in local coordinates.

Reimplement this function in a QGraphicsItem subclass to provide the item's painting implementation, using painter. The option parameter provides style options for the item, such as its state, exposed area and its level-of-detail hints. The widget argument is optional. If provided, it points to the widget that is being painted on; otherwise, it is 0.

    void RoundRectItem::paint(QPainter *painter,
                              const QStyleOptionGraphicsItem *option,
                              QWidget *widget)
    {
        painter->drawRoundRect(-10, -10, 20, 20);
    }

The painter's pen is 0-width by default, and its pen is initialized to the QPalette::Text brush from the paint device's palette. The brush is initialized to QPalette::Window.

All painting is done in local coordinates.

Specified by:
paint in interface QGraphicsItemInterface

sceneEvent

public boolean sceneEvent(QEvent event)

This virtual function receives events to this item. Reimplement this function to intercept events before they are dispatched to the specialized event handlers contextMenuEvent, focusInEvent, focusOutEvent, hoverEnterEvent, hoverMoveEvent, hoverLeaveEvent, keyPressEvent, keyReleaseEvent, mousePressEvent, mouseReleaseEvent, mouseMoveEvent, and mouseDoubleClickEvent.

Returns true if the event was recognized and handled; otherwise, (e.g., if the event type was not recognized,) false is returned.

event is the intercepted event.

Specified by:
sceneEvent in interface QGraphicsItemInterface

sceneEventFilter

public boolean sceneEventFilter(QGraphicsItemInterface watched,
                                QEvent event)

Filters events for the item watched. event is the filtered event.

Reimplementing this function in a subclass makes it possible for the item to be used as an event filter for other items, intercepting all the events send to those items before they are able to respond.

Reimplementations must return true to prevent further processing of a given event, ensuring that it will not be delivered to the watched item, or return false to indicate that the event should be propagated further by the event system.

Specified by:
sceneEventFilter in interface QGraphicsItemInterface
See Also:
installSceneEventFilter

setExtension

public void setExtension(QGraphicsItem.Extension extension,
                         java.lang.Object variant)

Specified by:
setExtension in interface QGraphicsItemInterface
See Also:
extension

shape

public QPainterPath shape()

Returns the shape of this item as a QPainterPath in local coordinates. The shape is used for many things, including collision detection, hit tests, and for the QGraphicsScene::items() functions.

The default implementation calls boundingRect to return a simple rectangular shape, but subclasses can reimplement this function to return a more accurate shape for non-rectangular items. For example, a round item may choose to return an elliptic shape for better collision detection. For example:

    QPainterPath RoundItem::shape() const
    {
        QPainterPath path;
        path.addEllipse(boundingRect());
        return path;
    }

This function is called by the default implementations of contains and collidesWithPath.

Specified by:
shape in interface QGraphicsItemInterface
See Also:
boundingRect, contains, prepareGeometryChange

supportsExtension

public boolean supportsExtension(QGraphicsItem.Extension extension)

Specified by:
supportsExtension in interface QGraphicsItemInterface

type

public int type()

Returns the type of an item as an int. All standard graphicsitem classes are associated with a unique value; see QGraphicsItem::Type. This type information is used by qgraphicsitem_cast() to distinguish between types.

Reimplementing this function and declaring a Type enum value equal to your custom item's type will enable use of qgraphicsitem_cast() with the item. Custom items must return a value larger than or equal to UserType (65536).

The default implementation (in QGraphicsItem) returns UserType.

Specified by:
type in interface QGraphicsItemInterface

wheelEvent

public void wheelEvent(QGraphicsSceneWheelEvent event)

This event handler, for event event, can be reimplemented to receive wheel events for this item. If you reimplement this function, event will be accepted by default.

If you ignore the event, (i.e., by calling QEvent::ignore(),) it will propagate to any item beneath this item. If no items accept the event, it will be ignored by the scene, and propagate to the view (e.g., the view's vertical scroll bar).

The default implementation ignores the event.

Specified by:
wheelEvent in interface QGraphicsItemInterface
See Also:
sceneEvent

fromNativePointer

public static QAbstractGraphicsShapeItem fromNativePointer(QNativePointer nativePointer)
This function returns the QAbstractGraphicsShapeItem instance pointed to by nativePointer

Parameters:
nativePointer - the QNativePointer of which object should be returned.

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