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QtGui.IQGraphicsItem Interface Reference

The QGraphicsItem class is the base class for all graphical items in a QGraphicsScene. More...

Inheritance diagram for QtGui.IQGraphicsItem:

Public Member Functions

void Advance (int phase)
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new QRegion BoundingRegion (QTransform itemToDeviceTransform)
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new void ClearFocus ()
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bool CollidesWithItem (IQGraphicsItem other, Qt.ItemSelectionMode mode=Qt.ItemSelectionMode.IntersectsItemShape)
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bool CollidesWithPath (QPainterPath path, Qt.ItemSelectionMode mode=Qt.ItemSelectionMode.IntersectsItemShape)
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new
System.Collections.Generic.List
< IQGraphicsItem
CollidingItems (Qt.ItemSelectionMode mode=Qt.ItemSelectionMode.IntersectsItemShape)
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new IQGraphicsItem CommonAncestorItem (IQGraphicsItem other)
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bool Contains (QPointF point)
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new object Data (int key)
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new QTransform DeviceTransform (QTransform viewportTransform)
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new void EnsureVisible ()
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new void EnsureVisible (QRectF rect, int xmargin=50, int ymargin=50)
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new void EnsureVisible (double x, double y, double w, double h, int xmargin=50, int ymargin=50)
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new IQGraphicsItem FocusItem ()
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new IQGraphicsItem FocusScopeItem ()
 
new void GrabKeyboard ()
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new void GrabMouse ()
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new void Hide ()
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new void InstallSceneEventFilter (IQGraphicsItem filterItem)
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new bool IsAncestorOf (IQGraphicsItem child)
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new bool IsBlockedByModalPanel (IQGraphicsItem blockingPanel=null)
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new bool IsObscured ()
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new bool IsObscured (QRectF rect)
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new bool IsObscured (double x, double y, double w, double h)
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bool IsObscuredBy (IQGraphicsItem item)
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new bool IsVisibleTo (IQGraphicsItem parent)
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new QTransform ItemTransform (IQGraphicsItem other)
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new QTransform ItemTransform (IQGraphicsItem other, ref bool ok)
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new QPolygonF MapFromItem (IQGraphicsItem item, QRectF rect)
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new QPainterPath MapFromItem (IQGraphicsItem item, QPainterPath path)
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new QPointF MapFromItem (IQGraphicsItem item, QPointF point)
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new QPolygonF MapFromItem (IQGraphicsItem item, QPolygonF polygon)
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new QPointF MapFromItem (IQGraphicsItem item, double x, double y)
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new QPolygonF MapFromItem (IQGraphicsItem item, double x, double y, double w, double h)
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new QPolygonF MapFromParent (QPolygonF polygon)
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new QPolygonF MapFromParent (QRectF rect)
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new QPainterPath MapFromParent (QPainterPath path)
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new QPointF MapFromParent (QPointF point)
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new QPointF MapFromParent (double x, double y)
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new QPolygonF MapFromParent (double x, double y, double w, double h)
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new QPolygonF MapFromScene (QPolygonF polygon)
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new QPolygonF MapFromScene (QRectF rect)
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new QPainterPath MapFromScene (QPainterPath path)
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new QPointF MapFromScene (QPointF point)
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new QPointF MapFromScene (double x, double y)
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new QPolygonF MapFromScene (double x, double y, double w, double h)
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new QRectF MapRectFromItem (IQGraphicsItem item, QRectF rect)
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new QRectF MapRectFromItem (IQGraphicsItem item, double x, double y, double w, double h)
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new QRectF MapRectFromParent (QRectF rect)
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new QRectF MapRectFromParent (double x, double y, double w, double h)
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new QRectF MapRectFromScene (QRectF rect)
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new QRectF MapRectFromScene (double x, double y, double w, double h)
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new QRectF MapRectToItem (IQGraphicsItem item, QRectF rect)
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new QRectF MapRectToItem (IQGraphicsItem item, double x, double y, double w, double h)
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new QRectF MapRectToParent (QRectF rect)
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new QRectF MapRectToParent (double x, double y, double w, double h)
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new QRectF MapRectToScene (QRectF rect)
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new QRectF MapRectToScene (double x, double y, double w, double h)
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new QPainterPath MapToItem (IQGraphicsItem item, QPainterPath path)
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new QPolygonF MapToItem (IQGraphicsItem item, QRectF rect)
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new QPolygonF MapToItem (IQGraphicsItem item, QPolygonF polygon)
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new QPointF MapToItem (IQGraphicsItem item, QPointF point)
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new QPointF MapToItem (IQGraphicsItem item, double x, double y)
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new QPolygonF MapToItem (IQGraphicsItem item, double x, double y, double w, double h)
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new QPolygonF MapToParent (QPolygonF polygon)
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new QPainterPath MapToParent (QPainterPath path)
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new QPointF MapToParent (QPointF point)
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new QPolygonF MapToParent (QRectF rect)
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new QPointF MapToParent (double x, double y)
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new QPolygonF MapToParent (double x, double y, double w, double h)
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new QPolygonF MapToScene (QPolygonF polygon)
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new QPointF MapToScene (QPointF point)
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new QPainterPath MapToScene (QPainterPath path)
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new QPolygonF MapToScene (QRectF rect)
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new QPointF MapToScene (double x, double y)
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new QPolygonF MapToScene (double x, double y, double w, double h)
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new void MoveBy (double dx, double dy)
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void Paint (QPainter painter, QStyleOptionGraphicsItem option, QWidget widget=null)
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new void RemoveSceneEventFilter (IQGraphicsItem filterItem)
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new void ResetMatrix ()
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new void ResetTransform ()
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new void Rotate (double angle)
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new double Scale ()
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new void Scale (double sx, double sy)
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new void Scroll (double dx, double dy)
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new void Scroll (double dx, double dy, QRectF rect)
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new void SetActive (bool active)
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new void SetCacheMode (QGraphicsItem.CacheMode mode, QSize cacheSize)
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new void SetData (int key, object value)
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new void SetEnabled (bool enabled)
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new void SetFlag (QGraphicsItem.GraphicsItemFlag flag, bool enabled=true)
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new void SetFocus (Qt.FocusReason focusReason=Qt.FocusReason.OtherFocusReason)
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new void SetMatrix (QMatrix matrix, bool combine=false)
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new void SetPos (double x, double y)
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new void SetScale (double scale)
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new void SetSelected (bool selected)
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new void SetTransform (QTransform matrix, bool combine=false)
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new void SetTransformOriginPoint (double ax, double ay)
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new void SetVisible (bool visible)
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new void Shear (double sh, double sv)
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new void Show ()
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new void StackBefore (IQGraphicsItem sibling)
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new QGraphicsObject ToGraphicsObject ()
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new void Translate (double dx, double dy)
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new void UngrabKeyboard ()
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new void UngrabMouse ()
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new void UnsetCursor ()
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new void Update ()
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new void Update (QRectF rect)
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new void Update (double x, double y, double width, double height)
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Properties

System.Boolean AcceptDrops [get, set]
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System.Boolean AcceptHoverEvents [get, set]
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System.Boolean AcceptTouchEvents [get, set]
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Qt.MouseButton AcceptedMouseButtons [get, set]
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System.Boolean AcceptsHoverEvents [get, set]
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System.Double BoundingRegionGranularity [get, set]
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QGraphicsItem.CacheMode cacheMode [get, set]
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QCursor Cursor [get, set]
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System.Boolean FiltersChildEvents [get, set]
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QGraphicsItem.GraphicsItemFlag Flags [get, set]
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IQGraphicsItem FocusProxy [get, set]
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QGraphicsEffect GraphicsEffect [get, set]
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QGraphicsItemGroup Group [get, set]
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System.Boolean HandlesChildEvents [get, set]
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Qt.InputMethodHint InputMethodHints [get, set]
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System.Double Opacity [get, set]
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QGraphicsItem.PanelModality panelModality [get, set]
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IQGraphicsItem ParentItem [get, set]
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QPointF Pos [get, set]
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System.Double Rotation [get, set]
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System.String ToolTip [get, set]
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QPointF TransformOriginPoint [get, set]
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System.Collections.Generic.List
< QGraphicsTransform
Transformations [get, set]
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System.Double X [get, set]
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System.Double Y [get, set]
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System.Double ZValue [get, set]
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QMatrix Matrix [get]
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QTransform Transform [get]
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QRectF BoundingRect [get]
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System.Collections.Generic.List
< IQGraphicsItem
ChildItems [get]
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System.Collections.Generic.List
< IQGraphicsItem
Children [get]
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QRectF ChildrenBoundingRect [get]
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QPainterPath ClipPath [get]
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System.Double EffectiveOpacity [get]
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System.Boolean HasCursor [get]
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System.Boolean HasFocus [get]
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System.Boolean IsActive [get]
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System.Boolean IsClipped [get]
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System.Boolean IsEnabled [get]
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System.Boolean IsPanel [get]
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System.Boolean IsSelected [get]
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System.Boolean IsUnderMouse [get]
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System.Boolean IsVisible [get]
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System.Boolean IsWidget [get]
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System.Boolean IsWindow [get]
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QPainterPath OpaqueArea [get]
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IQGraphicsItem Panel [get]
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QGraphicsObject ParentObject [get]
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QGraphicsWidget ParentWidget [get]
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QGraphicsScene Scene [get]
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QRectF SceneBoundingRect [get]
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QMatrix SceneMatrix [get]
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QPointF ScenePos [get]
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QTransform SceneTransform [get]
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QPainterPath Shape [get]
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IQGraphicsItem TopLevelItem [get]
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QGraphicsWidget TopLevelWidget [get]
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System.Int32 Type [get]
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QGraphicsWidget Window [get]
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Detailed Description

The QGraphicsItem class is the base class for all graphical items in a QGraphicsScene.

It provides a light-weight foundation for writing your own custom items. This includes defining the item's geometry, collision detection, its painting implementation and item interaction through its event handlers. QGraphicsItem is part of the Graphics View Framework

For convenience, Qt provides a set of standard graphics items for the most common shapes. These are:

QGraphicsEllipseItem provides an ellipse item

QGraphicsLineItem provides a line item

QGraphicsPathItem provides an arbitrary path item

QGraphicsPixmapItem provides a pixmap item

QGraphicsPolygonItem provides a polygon item

QGraphicsRectItem provides a rectangular item

QGraphicsSimpleTextItem provides a simple text label item

QGraphicsTextItem provides an advanced text browser item

All of an item's geometric information is based on its local coordinate system. The item's position, pos(), is the only function that does not operate in local coordinates, as it returns a position in parent coordinates. The Graphics View Coordinate System describes the coordinate system in detail.

You can set whether an item should be visible (i.e., drawn, and accepting events), by calling setVisible(). Hiding an item will also hide its children. Similarly, you can enable or disable an item by calling setEnabled(). If you disable an item, all its children will also be disabled. By default, items are both visible and enabled. To toggle whether an item is selected or not, first enable selection by setting the ItemIsSelectable flag, and then call setSelected(). Normally, selection is toggled by the scene, as a result of user interaction.

To write your own graphics item, you first create a subclass of QGraphicsItem, and then start by implementing its two pure virtual public functions: boundingRect(), which returns an estimate of the area painted by the item, and paint(), which implements the actual painting. For example:

class SimpleItem : public QGraphicsItem

{

public:

QRectF boundingRect() const

{

qreal penWidth = 1;

return QRectF(-10 - penWidth / 2, -10 - penWidth / 2,

20 + penWidth, 20 + penWidth);

}

void paint(QPainter *painter, const QStyleOptionGraphicsItem *option,

QWidget *widget)

{

painter->drawRoundedRect(-10, -10, 20, 20, 5, 5);

}

};

The boundingRect() function has many different purposes. QGraphicsScene bases its item index on boundingRect(), and QGraphicsView uses it both for culling invisible items, and for determining the area that needs to be recomposed when drawing overlapping items. In addition, QGraphicsItem's collision detection mechanisms use boundingRect() to provide an efficient cut-off. The fine grained collision algorithm in collidesWithItem() is based on calling shape(), which returns an accurate outline of the item's shape as a QPainterPath.

QGraphicsScene expects all items boundingRect() and shape() to remain unchanged unless it is notified. If you want to change an item's geometry in any way, you must first call prepareGeometryChange() to allow QGraphicsScene to update its bookkeeping.

Collision detection can be done in two ways:

Reimplement shape() to return an accurate shape for your item, and rely on the default implementation of collidesWithItem() to do shape-shape intersection. This can be rather expensive if the shapes are complex.

Reimplement collidesWithItem() to provide your own custom item and shape collision algorithm.

The contains() function can be called to determine whether the item contains a point or not. This function can also be reimplemented by the item. The default behavior of contains() is based on calling shape().

Items can contain other items, and also be contained by other items. All items can have a parent item and a list of children. Unless the item has no parent, its position is in parent coordinates (i.e., the parent's local coordinates). Parent items propagate both their position and their transformation to all children.

Transformations

QGraphicsItem supports projective transformations in addition to its base position, pos(). There are several ways to change an item's transformation. For simple transformations, you can call either of the convenience functions setRotation() or setScale(), or you can pass any transformation matrix to setTransform(). For advanced transformation control you also have the option of setting several combined transformations by calling setTransformations().

Item transformations accumulate from parent to child, so if both a parent and child item are rotated 90 degrees, the child's total transformation will be 180 degrees. Similarly, if the item's parent is scaled to 2x its original size, its children will also be twice as large. An item's transformation does not affect its own local geometry; all geometry functions (e.g., contains(), update(), and all the mapping functions) still operate in local coordinates. For convenience, QGraphicsItem provides the functions sceneTransform(), which returns the item's total transformation matrix (including its position and all parents' positions and transformations), and scenePos(), which returns its position in scene coordinates. To reset an item's matrix, call resetTransform().

Certain transformation operations produce a different outcome depending on the order in which they are applied. For example, if you scale an transform, and then rotate it, you may get a different result than if the transform was rotated first. However, the order you set the transformation properties on QGraphicsItem does not affect the resulting transformation; QGraphicsItem always applies the properties in a fixed, defined order:

The item's base transform is applied (transform())

The item's transformations list is applied in order (transformations())

The item is rotated relative to its transform origin point (rotation(), transformOriginPoint())

The item is scaled relative to its transform origin point (scale(), transformOriginPoint())

Painting

The paint() function is called by QGraphicsView to paint the item's contents. The item has no background or default fill of its own; whatever is behind the item will shine through all areas that are not explicitly painted in this function. You can call update() to schedule a repaint, optionally passing the rectangle that needs a repaint. Depending on whether or not the item is visible in a view, the item may or may not be repainted; there is no equivalent to QWidget::repaint() in QGraphicsItem.

Items are painted by the view, starting with the parent items and then drawing children, in ascending stacking order. You can set an item's stacking order by calling setZValue(), and test it by calling zValue(), where items with low z-values are painted before items with high z-values. Stacking order applies to sibling items; parents are always drawn before their children.

Sorting

All items are drawn in a defined, stable order, and this same order decides which items will receive mouse input first when you click on the scene. Normally you don't have to worry about sorting, as the items follow a "natural order", following the logical structure of the scene.

An item's children are stacked on top of the parent, and sibling items are stacked by insertion order (i.e., in the same order that they were either added to the scene, or added to the same parent). If you add item A, and then B, then B will be on top of A. If you then add C, the items' stacking order will be A, then B, then C.

This example shows the stacking order of all limbs of the robot from the Drag and Drop Robot example. The torso is the root item (all other items are children or descendants of the torso), so it is drawn first. Next, the head is drawn, as it is the first item in the torso's list of children. Then the upper left arm is drawn. As the lower arm is a child of the upper arm, the lower arm is then drawn, followed by the upper arm's next sibling, which is the upper right arm, and so on.

For advanced users, there are ways to alter how your items are sorted:

You can call setZValue() on an item to explicitly stack it on top of, or under, other sibling items. The default Z value for an item is 0. Items with the same Z value are stacked by insertion order.

You can call stackBefore() to reorder the list of children. This will directly modify the insertion order.

You can set the ItemStacksBehindParent flag to stack a child item behind its parent.

The stacking order of two sibling items also counts for each item's children and descendant items. So if one item is on top of another, then all its children will also be on top of all the other item's children as well.

Events

QGraphicsItem receives events from QGraphicsScene through the virtual function sceneEvent(). This function distributes the most common events to a set of convenience event handlers:

contextMenuEvent() handles context menu events

focusInEvent() and focusOutEvent() handle focus in and out events

hoverEnterEvent(), hoverMoveEvent(), and hoverLeaveEvent() handles hover enter, move and leave events

inputMethodEvent() handles input events, for accessibility support

keyPressEvent() and keyReleaseEvent() handle key press and release events

mousePressEvent(), mouseMoveEvent(), mouseReleaseEvent(), and mouseDoubleClickEvent() handles mouse press, move, release, click and doubleclick events

You can filter events for any other item by installing event filters. This functionality is separate from Qt's regular event filters (see QObject::installEventFilter()), which only work on subclasses of QObject. After installing your item as an event filter for another item by calling installSceneEventFilter(), the filtered events will be received by the virtual function sceneEventFilter(). You can remove item event filters by calling removeSceneEventFilter().

Custom Data

Sometimes it's useful to register custom data with an item, be it a custom item, or a standard item. You can call setData() on any item to store data in it using a key-value pair (the key being an integer, and the value is a QVariant). To get custom data from an item, call data(). This functionality is completely untouched by Qt itself; it is provided for the user's convenience.

See also QGraphicsScene, QGraphicsView, and Graphics View Framework.

Member Function Documentation

void QtGui.IQGraphicsItem.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().

See also QGraphicsItemAnimation and QTimeLine.

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new QRegion QtGui.IQGraphicsItem.BoundingRegion ( QTransform  itemToDeviceTransform)

Returns the bounding region for this item. The coordinate space of the returned region depends on itemToDeviceTransform. If you pass an identity QTransform as a parameter, this function will return a local coordinate region.

The bounding region describes a coarse outline of the item's visual contents. Although it's expensive to calculate, it's also more precise than boundingRect(), and it can help to avoid unnecessary repainting when an item is updated. This is particularly efficient for thin items (e.g., lines or simple polygons). You can tune the granularity for the bounding region by calling setBoundingRegionGranularity(). The default granularity is 0; in which the item's bounding region is the same as its bounding rect.

itemToDeviceTransform is the transformation from item coordinates to device coordinates. If you want this function to return a QRegion in scene coordinates, you can pass sceneTransform() as an argument.

This function was introduced in Qt 4.4.

See also boundingRegionGranularity().

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new void QtGui.IQGraphicsItem.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, or widgets that set an appropriate focus policy, can accept keyboard focus.

See also setFocus(), hasFocus(), and QGraphicsWidget::focusPolicy.

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

bool QtGui.IQGraphicsItem.CollidesWithItem ( IQGraphicsItem  other,
Qt.ItemSelectionMode  mode = Qt.ItemSelectionMode.IntersectsItemShape 
)

Returns true if this item collides with other; otherwise returns false.

The mode is applied to other, and the resulting shape or bounding rectangle is then compared to this item's shape. The default value for mode is Qt::IntersectsItemShape; other collides with this item if it either intersects, contains, or is contained by this item's shape (see Qt::ItemSelectionMode for details).

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.

See also contains() and shape().

Implemented in QtGui.QGraphicsItem.

bool QtGui.IQGraphicsItem.CollidesWithPath ( QPainterPath  path,
Qt.ItemSelectionMode  mode = Qt.ItemSelectionMode.IntersectsItemShape 
)

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, contains, or is contained by this item's shape.

Note that this function checks whether the item's shape or bounding rectangle (depending on mode) is contained within path, and not whether path is contained within the items shape or bounding rectangle.

See also collidesWithItem(), contains(), and shape().

Implemented in QtGui.QGraphicsItem.

new System.Collections.Generic.List<IQGraphicsItem> QtGui.IQGraphicsItem.CollidingItems ( Qt.ItemSelectionMode  mode = Qt.ItemSelectionMode.IntersectsItemShape)

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

The way collisions are detected is determined by applying mode to items that are compared to this item, i.e., each item's shape or bounding rectangle is checked against this item's shape. The default value for mode is Qt::IntersectsItemShape.

See also collidesWithItem().

Implemented in QtGui.QGraphicsItem.

new IQGraphicsItem QtGui.IQGraphicsItem.CommonAncestorItem ( IQGraphicsItem  other)

Returns the closest common ancestor item of this item and other, or 0 if either other is 0, or there is no common ancestor.

This function was introduced in Qt 4.4.

See also isAncestorOf().

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

bool QtGui.IQGraphicsItem.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.

See also shape(), boundingRect(), and collidesWithPath().

Implemented in QtGui.QGraphicsTextItem, QtGui.QGraphicsSimpleTextItem, QtGui.QGraphicsRectItem, QtGui.QGraphicsPolygonItem, QtGui.QGraphicsPixmapItem, QtGui.QGraphicsPathItem, QtGui.QGraphicsObject, QtGui.QGraphicsLineItem, QtGui.QGraphicsItem, and QtGui.QGraphicsEllipseItem.

new object QtGui.IQGraphicsItem.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.

See also setData().

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new QTransform QtGui.IQGraphicsItem.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 it also understands the ItemIgnoresTransformations flag. The device transform can be used to do accurate coordinate mapping (and collision detection) for untransformable items.

This function was introduced in Qt 4.3.

See also transform(), setTransform(), scenePos(), The Graphics View Coordinate System, and itemTransform().

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new void QtGui.IQGraphicsItem.EnsureVisible ( )

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.

See also QGraphicsView::ensureVisible().

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new void QtGui.IQGraphicsItem.EnsureVisible ( QRectF  rect,
int  xmargin = 50,
int  ymargin = 50 
)

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.

See also QGraphicsView::ensureVisible().

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new void QtGui.IQGraphicsItem.EnsureVisible ( double  x,
double  y,
double  w,
double  h,
int  xmargin = 50,
int  ymargin = 50 
)

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

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new IQGraphicsItem QtGui.IQGraphicsItem.FocusItem ( )

If this item, a child or descendant of this item currently has input focus, this function will return a pointer to that item. If no descendant has input focus, 0 is returned.

This function was introduced in Qt 4.6.

See also hasFocus(), setFocus(), and QWidget::focusWidget().

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new IQGraphicsItem QtGui.IQGraphicsItem.FocusScopeItem ( )
new void QtGui.IQGraphicsItem.GrabKeyboard ( )

Grabs the keyboard input.

The item will receive all keyboard input to the scene until one of the following events occur:

The item becomes invisible

The item is removed from the scene

The item is deleted

The item calls ungrabKeyboard()

Another item calls grabKeyboard(); the item will regain the keyboard grab when the other item calls ungrabKeyboard().

When an item gains the keyboard grab, it receives a QEvent::GrabKeyboard event. When it loses the keyboard grab, it receives a QEvent::UngrabKeyboard event. These events can be used to detect when your item gains or loses the keyboard grab through other means than gaining input focus.

It is almost never necessary to explicitly grab the keyboard in Qt, as Qt grabs and releases it sensibly. In particular, Qt grabs the keyboard when your item gains input focus, and releases it when your item loses input focus, or when the item is hidden.

Note that only visible items can grab keyboard input. Calling grabKeyboard() on an invisible item has no effect.

Keyboard events are not affected.

This function was introduced in Qt 4.4.

See also ungrabKeyboard(), grabMouse(), and setFocus().

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new void QtGui.IQGraphicsItem.GrabMouse ( )

Grabs the mouse input.

This item will receive all mouse events for the scene until any of the following events occurs:

The item becomes invisible

The item is removed from the scene

The item is deleted

The item call ungrabMouse()

Another item calls grabMouse(); the item will regain the mouse grab when the other item calls ungrabMouse().

When an item gains the mouse grab, it receives a QEvent::GrabMouse event. When it loses the mouse grab, it receives a QEvent::UngrabMouse event. These events can be used to detect when your item gains or loses the mouse grab through other means than receiving mouse button events.

It is almost never necessary to explicitly grab the mouse in Qt, as Qt grabs and releases it sensibly. In particular, Qt grabs the mouse when you press a mouse button, and keeps the mouse grabbed until you release the last mouse button. Also, Qt::Popup widgets implicitly call grabMouse() when shown, and ungrabMouse() when hidden.

Note that only visible items can grab mouse input. Calling grabMouse() on an invisible item has no effect.

Keyboard events are not affected.

This function was introduced in Qt 4.4.

See also QGraphicsScene::mouseGrabberItem(), ungrabMouse(), and grabKeyboard().

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new void QtGui.IQGraphicsItem.Hide ( )

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

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

See also show() and setVisible().

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new void QtGui.IQGraphicsItem.InstallSceneEventFilter ( IQGraphicsItem  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.

Items must belong to a scene for scene event filters to be installed and used.

See also removeSceneEventFilter(), sceneEventFilter(), and sceneEvent().

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new bool QtGui.IQGraphicsItem.IsAncestorOf ( IQGraphicsItem  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).

See also parentItem().

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new bool QtGui.IQGraphicsItem.IsBlockedByModalPanel ( IQGraphicsItem  blockingPanel = null)

Returns true if this item is blocked by a modal panel, false otherwise. If blockingPanel is non-zero, blockingPanel will be set to the modal panel that is blocking this item. If this item is not blocked, blockingPanel will not be set by this function.

This function always returns false for items not in a scene.

This function was introduced in Qt 4.6.

See also panelModality(), setPanelModality(), and PanelModality.

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new bool QtGui.IQGraphicsItem.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.

See also opaqueArea().

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new bool QtGui.IQGraphicsItem.IsObscured ( QRectF  rect)

This is an overloaded function.

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().

This function was introduced in Qt 4.3.

See also opaqueArea().

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new bool QtGui.IQGraphicsItem.IsObscured ( double  x,
double  y,
double  w,
double  h 
)

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

This function was introduced in Qt 4.3.

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

bool QtGui.IQGraphicsItem.IsObscuredBy ( IQGraphicsItem  item)

Returns true if this item's bounding rect is completely obscured by the opaque shape of item.

The base implementation maps item's opaqueArea() to this item's coordinate system, and then checks if this item's boundingRect() is fully contained within the mapped shape.

You can reimplement this function to provide a custom algorithm for determining whether this item is obscured by item.

See also opaqueArea() and isObscured().

Implemented in QtGui.QGraphicsTextItem, QtGui.QGraphicsSimpleTextItem, QtGui.QGraphicsRectItem, QtGui.QGraphicsPolygonItem, QtGui.QGraphicsPixmapItem, QtGui.QGraphicsPathItem, QtGui.QGraphicsObject, QtGui.QGraphicsLineItem, QtGui.QGraphicsItemGroup, QtGui.QGraphicsItem, QtGui.QGraphicsEllipseItem, and QtGui.QAbstractGraphicsShapeItem.

new bool QtGui.IQGraphicsItem.IsVisibleTo ( IQGraphicsItem  parent)

Returns true if the item is visible to parent; otherwise, false is returned. parent can be 0, in which case this function will return whether the item is visible to the scene or not.

An item may not be visible to its ancestors even if isVisible() is true. It may also be visible to its ancestors even if isVisible() is false. If any ancestor is hidden, the item itself will be implicitly hidden, in which case this function will return false.

This function was introduced in Qt 4.4.

See also isVisible() and setVisible().

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new QTransform QtGui.IQGraphicsItem.ItemTransform ( IQGraphicsItem  other)

Returns a QTransform that maps coordinates from this item to other. If ok is not null, and if there is no such transform, the boolean pointed to by ok will be set to false; otherwise it will be set to true.

This transform provides an alternative to the mapToItem() or mapFromItem() functions, by returning the appropriate transform so that you can map shapes and coordinates yourself. It also helps you write more efficient code when repeatedly mapping between the same two items.

Note: In rare circumstances, there is no transform that maps between two items.

This function was introduced in Qt 4.5.

See also mapToItem(), mapFromItem(), and deviceTransform().

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new QTransform QtGui.IQGraphicsItem.ItemTransform ( IQGraphicsItem  other,
ref bool  ok 
)

Returns a QTransform that maps coordinates from this item to other. If ok is not null, and if there is no such transform, the boolean pointed to by ok will be set to false; otherwise it will be set to true.

This transform provides an alternative to the mapToItem() or mapFromItem() functions, by returning the appropriate transform so that you can map shapes and coordinates yourself. It also helps you write more efficient code when repeatedly mapping between the same two items.

Note: In rare circumstances, there is no transform that maps between two items.

This function was introduced in Qt 4.5.

See also mapToItem(), mapFromItem(), and deviceTransform().

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new QPolygonF QtGui.IQGraphicsItem.MapFromItem ( IQGraphicsItem  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()

See also itemTransform(), mapToItem(), mapFromParent(), transform(), and The Graphics View Coordinate System.

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new QPainterPath QtGui.IQGraphicsItem.MapFromItem ( IQGraphicsItem  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().

See also itemTransform(), mapFromParent(), mapFromScene(), mapToItem(), and The Graphics View Coordinate System.

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new QPointF QtGui.IQGraphicsItem.MapFromItem ( IQGraphicsItem  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().

See also itemTransform(), mapFromParent(), mapFromScene(), transform(), mapToItem(), and The Graphics View Coordinate System.

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new QPolygonF QtGui.IQGraphicsItem.MapFromItem ( IQGraphicsItem  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().

See also itemTransform(), mapToItem(), mapFromParent(), transform(), and The Graphics View Coordinate System.

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new QPointF QtGui.IQGraphicsItem.MapFromItem ( IQGraphicsItem  item,
double  x,
double  y 
)

This is an overloaded function.

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

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new QPolygonF QtGui.IQGraphicsItem.MapFromItem ( IQGraphicsItem  item,
double  x,
double  y,
double  w,
double  h 
)

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

This function was introduced in Qt 4.3.

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new QPolygonF QtGui.IQGraphicsItem.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.

See also mapToParent(), mapToItem(), transform(), and The Graphics View Coordinate System.

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new QPolygonF QtGui.IQGraphicsItem.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.

See also mapToParent(), mapFromItem(), transform(), and The Graphics View Coordinate System.

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new QPainterPath QtGui.IQGraphicsItem.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.

See also mapFromScene(), mapFromItem(), mapToParent(), and The Graphics View Coordinate System.

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new QPointF QtGui.IQGraphicsItem.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.

See also mapFromItem(), mapFromScene(), transform(), mapToParent(), and The Graphics View Coordinate System.

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new QPointF QtGui.IQGraphicsItem.MapFromParent ( double  x,
double  y 
)

This is an overloaded function.

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

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new QPolygonF QtGui.IQGraphicsItem.MapFromParent ( double  x,
double  y,
double  w,
double  h 
)

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

This function was introduced in Qt 4.3.

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new QPolygonF QtGui.IQGraphicsItem.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.

See also mapToScene(), mapFromParent(), transform(), and The Graphics View Coordinate System.

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new QPolygonF QtGui.IQGraphicsItem.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.

See also mapToScene(), mapFromItem(), transform(), and The Graphics View Coordinate System.

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new QPainterPath QtGui.IQGraphicsItem.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.

See also mapFromParent(), mapFromItem(), mapToScene(), and The Graphics View Coordinate System.

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new QPointF QtGui.IQGraphicsItem.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.

See also mapFromItem(), mapFromParent(), transform(), mapToScene(), and The Graphics View Coordinate System.

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new QPointF QtGui.IQGraphicsItem.MapFromScene ( double  x,
double  y 
)

This is an overloaded function.

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

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new QPolygonF QtGui.IQGraphicsItem.MapFromScene ( double  x,
double  y,
double  w,
double  h 
)

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

This function was introduced in Qt 4.3.

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new QRectF QtGui.IQGraphicsItem.MapRectFromItem ( IQGraphicsItem  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 new rectangle (i.e., the bounding rectangle of the resulting polygon).

If item is 0, this function returns the same as mapRectFromScene().

This function was introduced in Qt 4.5.

See also itemTransform(), mapToParent(), mapToScene(), mapFromItem(), and The Graphics View Coordinate System.

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new QRectF QtGui.IQGraphicsItem.MapRectFromItem ( IQGraphicsItem  item,
double  x,
double  y,
double  w,
double  h 
)

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

This function was introduced in Qt 4.5.

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new QRectF QtGui.IQGraphicsItem.MapRectFromParent ( 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 new rectangle (i.e., the bounding rectangle of the resulting polygon).

This function was introduced in Qt 4.5.

See also itemTransform(), mapToParent(), mapToScene(), mapFromItem(), and The Graphics View Coordinate System.

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new QRectF QtGui.IQGraphicsItem.MapRectFromParent ( double  x,
double  y,
double  w,
double  h 
)

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

This function was introduced in Qt 4.5.

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new QRectF QtGui.IQGraphicsItem.MapRectFromScene ( QRectF  rect)

Maps the rectangle rect, which is in scene coordinates, to this item's coordinate system, and returns the mapped rectangle as a new rectangle (i.e., the bounding rectangle of the resulting polygon).

This function was introduced in Qt 4.5.

See also itemTransform(), mapToParent(), mapToScene(), mapFromItem(), and The Graphics View Coordinate System.

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new QRectF QtGui.IQGraphicsItem.MapRectFromScene ( double  x,
double  y,
double  w,
double  h 
)

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

This function was introduced in Qt 4.5.

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new QRectF QtGui.IQGraphicsItem.MapRectToItem ( IQGraphicsItem  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 new rectangle (i.e., the bounding rectangle of the resulting polygon).

If item is 0, this function returns the same as mapRectToScene().

This function was introduced in Qt 4.5.

See also itemTransform(), mapToParent(), mapToScene(), mapFromItem(), and The Graphics View Coordinate System.

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new QRectF QtGui.IQGraphicsItem.MapRectToItem ( IQGraphicsItem  item,
double  x,
double  y,
double  w,
double  h 
)

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

This function was introduced in Qt 4.5.

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new QRectF QtGui.IQGraphicsItem.MapRectToParent ( 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 new rectangle (i.e., the bounding rectangle of the resulting polygon).

This function was introduced in Qt 4.5.

See also itemTransform(), mapToParent(), mapToScene(), mapFromItem(), and The Graphics View Coordinate System.

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new QRectF QtGui.IQGraphicsItem.MapRectToParent ( double  x,
double  y,
double  w,
double  h 
)

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

This function was introduced in Qt 4.5.

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new QRectF QtGui.IQGraphicsItem.MapRectToScene ( QRectF  rect)

Maps the rectangle rect, which is in this item's coordinate system, to the scene coordinate system, and returns the mapped rectangle as a new rectangle (i.e., the bounding rectangle of the resulting polygon).

This function was introduced in Qt 4.5.

See also itemTransform(), mapToParent(), mapToScene(), mapFromItem(), and The Graphics View Coordinate System.

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new QRectF QtGui.IQGraphicsItem.MapRectToScene ( double  x,
double  y,
double  w,
double  h 
)

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

This function was introduced in Qt 4.5.

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new QPainterPath QtGui.IQGraphicsItem.MapToItem ( IQGraphicsItem  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().

See also itemTransform(), mapToParent(), mapToScene(), mapFromItem(), and The Graphics View Coordinate System.

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new QPolygonF QtGui.IQGraphicsItem.MapToItem ( IQGraphicsItem  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().

See also itemTransform(), mapToParent(), mapToScene(), mapFromItem(), and The Graphics View Coordinate System.

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new QPolygonF QtGui.IQGraphicsItem.MapToItem ( IQGraphicsItem  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().

See also itemTransform(), mapToParent(), mapToScene(), mapFromItem(), and The Graphics View Coordinate System.

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new QPointF QtGui.IQGraphicsItem.MapToItem ( IQGraphicsItem  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().

See also itemTransform(), mapToParent(), mapToScene(), transform(), mapFromItem(), and The Graphics View Coordinate System.

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new QPointF QtGui.IQGraphicsItem.MapToItem ( IQGraphicsItem  item,
double  x,
double  y 
)

This is an overloaded function.

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

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new QPolygonF QtGui.IQGraphicsItem.MapToItem ( IQGraphicsItem  item,
double  x,
double  y,
double  w,
double  h 
)

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

This function was introduced in Qt 4.3.

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new QPolygonF QtGui.IQGraphicsItem.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.

See also mapToScene(), mapToItem(), mapFromParent(), and The Graphics View Coordinate System.

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new QPainterPath QtGui.IQGraphicsItem.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.

See also mapToScene(), mapToItem(), mapFromParent(), and The Graphics View Coordinate System.

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new QPointF QtGui.IQGraphicsItem.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.

See also mapToItem(), mapToScene(), transform(), mapFromParent(), and The Graphics View Coordinate System.

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new QPolygonF QtGui.IQGraphicsItem.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.

See also mapToScene(), mapToItem(), mapFromParent(), and The Graphics View Coordinate System.

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new QPointF QtGui.IQGraphicsItem.MapToParent ( double  x,
double  y 
)

This is an overloaded function.

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

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new QPolygonF QtGui.IQGraphicsItem.MapToParent ( double  x,
double  y,
double  w,
double  h 
)

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

This function was introduced in Qt 4.3.

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new QPolygonF QtGui.IQGraphicsItem.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.

See also mapToParent(), mapToItem(), mapFromScene(), and The Graphics View Coordinate System.

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new QPointF QtGui.IQGraphicsItem.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.

See also mapToItem(), mapToParent(), transform(), mapFromScene(), and The Graphics View Coordinate System.

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new QPainterPath QtGui.IQGraphicsItem.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.

See also mapToParent(), mapToItem(), mapFromScene(), and The Graphics View Coordinate System.

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new QPolygonF QtGui.IQGraphicsItem.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.

See also mapToParent(), mapToItem(), mapFromScene(), and The Graphics View Coordinate System.

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new QPointF QtGui.IQGraphicsItem.MapToScene ( double  x,
double  y 
)

This is an overloaded function.

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

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new QPolygonF QtGui.IQGraphicsItem.MapToScene ( double  x,
double  y,
double  w,
double  h 
)

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

This function was introduced in Qt 4.3.

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new void QtGui.IQGraphicsItem.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)).

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

void QtGui.IQGraphicsItem.Paint ( QPainter  painter,
QStyleOptionGraphicsItem  option,
QWidget  widget = null 
)

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. For cached painting, widget is always 0.

void RoundRectItem::paint(QPainter *painter,

const QStyleOptionGraphicsItem *option,

QWidget *widget)

{

painter->drawRoundedRect(-10, -10, 20, 20, 5, 5);

}

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.

Make sure to constrain all painting inside the boundaries of boundingRect() to avoid rendering artifacts (as QGraphicsView does not clip the painter for you). In particular, when QPainter renders the outline of a shape using an assigned QPen, half of the outline will be drawn outside, and half inside, the shape you're rendering (e.g., with a pen width of 2 units, you must draw outlines 1 unit inside boundingRect()). QGraphicsItem does not support use of cosmetic pens with a non-zero width.

All painting is done in local coordinates.

See also setCacheMode(), QPen::width(), Item Coordinates, and ItemUsesExtendedStyleOption.

Implemented in QtGui.QGraphicsWidget, QtGui.QGraphicsTextItem, QtGui.QGraphicsSimpleTextItem, QtGui.QGraphicsRectItem, QtGui.QGraphicsProxyWidget, QtGui.QGraphicsPolygonItem, QtGui.QGraphicsPixmapItem, QtGui.QGraphicsPathItem, QtGui.QGraphicsObject, QtGui.QGraphicsLineItem, QtGui.QGraphicsItemGroup, QtGui.QGraphicsItem, QtGui.QGraphicsEllipseItem, and QtSvg.QGraphicsSvgItem.

new void QtGui.IQGraphicsItem.RemoveSceneEventFilter ( IQGraphicsItem  filterItem)

Removes an event filter on this item from filterItem.

See also installSceneEventFilter().

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new void QtGui.IQGraphicsItem.ResetMatrix ( )

Use resetTransform() instead.

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new void QtGui.IQGraphicsItem.ResetTransform ( )

Resets this item's transformation matrix to the identity matrix or all the transformation properties to their default values. This is equivalent to calling setTransform(QTransform()).

This function was introduced in Qt 4.3.

See also setTransform() and transform().

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new void QtGui.IQGraphicsItem.Rotate ( double  angle)

Use

setRotation(rotation() + angle);

instead.

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));

See also setTransform(), transform(), scale(), shear(), and translate().

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new double QtGui.IQGraphicsItem.Scale ( )

Returns the scale factor of the item. The default scale factor is 1.0 (i.e., the item is not scaled).

The scale is combined with the item's rotation(), transform() and transformations() to map the item's coordinate system to the parent item.

This function was introduced in Qt 4.6.

See also setScale(), rotation(), and Transformations.

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new void QtGui.IQGraphicsItem.Scale ( double  sx,
double  sy 
)

Use

setTransform(QTransform::fromScale(sx, sy), true);

instead.

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));

See also setTransform() and transform().

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new void QtGui.IQGraphicsItem.Scroll ( double  dx,
double  dy 
)

Scrolls the contents of rect by dx, dy. If rect is a null rect (the default), the item's bounding rect is scrolled.

Scrolling provides a fast alternative to simply redrawing when the contents of the item (or parts of the item) are shifted vertically or horizontally. Depending on the current transformation and the capabilities of the paint device (i.e., the viewport), this operation may consist of simply moving pixels from one location to another using memmove(). In most cases this is faster than rerendering the entire area.

After scrolling, the item will issue an update for the newly exposed areas. If scrolling is not supported (e.g., you are rendering to an OpenGL viewport, which does not benefit from scroll optimizations), this function is equivalent to calling update(rect).

Note: Scrolling is only supported when QGraphicsItem::ItemCoordinateCache is enabled; in all other cases calling this function is equivalent to calling update(rect). If you for sure know that the item is opaque and not overlapped by other items, you can map the rect to viewport coordinates and scroll the viewport.

QTransform xform = item->deviceTransform(view->viewportTransform());

QRect deviceRect = xform.mapRect(rect).toAlignedRect();

view->viewport()->scroll(dx, dy, deviceRect);

This function was introduced in Qt 4.4.

See also boundingRect().

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new void QtGui.IQGraphicsItem.Scroll ( double  dx,
double  dy,
QRectF  rect 
)

Scrolls the contents of rect by dx, dy. If rect is a null rect (the default), the item's bounding rect is scrolled.

Scrolling provides a fast alternative to simply redrawing when the contents of the item (or parts of the item) are shifted vertically or horizontally. Depending on the current transformation and the capabilities of the paint device (i.e., the viewport), this operation may consist of simply moving pixels from one location to another using memmove(). In most cases this is faster than rerendering the entire area.

After scrolling, the item will issue an update for the newly exposed areas. If scrolling is not supported (e.g., you are rendering to an OpenGL viewport, which does not benefit from scroll optimizations), this function is equivalent to calling update(rect).

Note: Scrolling is only supported when QGraphicsItem::ItemCoordinateCache is enabled; in all other cases calling this function is equivalent to calling update(rect). If you for sure know that the item is opaque and not overlapped by other items, you can map the rect to viewport coordinates and scroll the viewport.

QTransform xform = item->deviceTransform(view->viewportTransform());

QRect deviceRect = xform.mapRect(rect).toAlignedRect();

view->viewport()->scroll(dx, dy, deviceRect);

This function was introduced in Qt 4.4.

See also boundingRect().

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new void QtGui.IQGraphicsItem.SetActive ( bool  active)

If active is true, and the scene is active, this item's panel will be activated. Otherwise, the panel is deactivated.

If the item is not part of an active scene, active will decide what happens to the panel when the scene becomes active or the item is added to the scene. If true, the item's panel will be activated when the item is either added to the scene or the scene is activated. Otherwise, the item will stay inactive independent of the scene's activated state.

This function was introduced in Qt 4.6.

See also isPanel(), QGraphicsScene::setActivePanel(), and QGraphicsScene::isActive().

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new void QtGui.IQGraphicsItem.SetCacheMode ( QGraphicsItem.CacheMode  mode,
QSize  cacheSize 
)

Sets the item's cache mode to mode.

The optional logicalCacheSize argument is used only by ItemCoordinateCache mode, and describes the resolution of the cache buffer; if logicalCacheSize is (100, 100), QGraphicsItem will fit the item into 100x100 pixels in graphics memory, regardless of the logical size of the item itself. By default QGraphicsItem uses the size of boundingRect(). For all other cache modes than ItemCoordinateCache, logicalCacheSize is ignored.

Caching can speed up rendering if your item spends a significant time redrawing itself. In some cases the cache can also slow down rendering, in particular when the item spends less time redrawing than QGraphicsItem spends redrawing from the cache. When enabled, the item's paint() function will be called only once for each call to update(); for any subsequent repaint requests, the Graphics View framework will redraw from the cache. This approach works particularly well with QGLWidget, which stores all the cache as OpenGL textures.

Be aware that QPixmapCache's cache limit may need to be changed to obtain optimal performance.

You can read more about the different cache modes in the CacheMode documentation.

This function was introduced in Qt 4.4.

See also cacheMode(), CacheMode, and QPixmapCache::setCacheLimit().

Implemented in QtGui.QGraphicsObject.

new void QtGui.IQGraphicsItem.SetData ( int  key,
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.

See also data().

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new void QtGui.IQGraphicsItem.SetEnabled ( bool  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.

Note: If you install an event filter, you can still intercept events before they are delivered to items; this mechanism disregards the item's enabled state.

See also isEnabled().

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new void QtGui.IQGraphicsItem.SetFlag ( QGraphicsItem.GraphicsItemFlag  flag,
bool  enabled = true 
)

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

See also flags() and setFlags().

Implemented in QtGui.QGraphicsObject.

new void QtGui.IQGraphicsItem.SetFocus ( Qt.FocusReason  focusReason = Qt.FocusReason.OtherFocusReason)

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

If this item is not visible, not active, or not associated with a scene, it will not gain immediate input focus. However, it will be registered as the preferred focus item for its subtree of items, should it later become visible.

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.

See also clearFocus(), hasFocus(), focusItem(), and focusProxy().

Implemented in QtGui.QGraphicsItem.

new void QtGui.IQGraphicsItem.SetMatrix ( QMatrix  matrix,
bool  combine = false 
)

Sets the item's affine transformation matrix. This is a subset or the item's full transformation matrix, and might not represent the item's full transformation.

Use setTransform() instead.

See also matrix(), transform(), and The Graphics View Coordinate System.

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new void QtGui.IQGraphicsItem.SetPos ( double  x,
double  y 
)

This is an overloaded function.

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

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new void QtGui.IQGraphicsItem.SetScale ( double  scale)

Sets the scale factor of the item. The default scale factor is 1.0 (i.e., the item is not scaled). A scale factor of 0.0 will collapse the item to a single point. If you provide a negative scale factor, the item will be flipped and mirrored (i.e., rotated 180 degrees).

The item is scaled around its transform origin point, which by default is (0, 0). You can select a different transformation origin by calling setTransformOriginPoint().

The scale is combined with the item's rotation(), transform() and transformations() to map the item's coordinate system to the parent item.

This function was introduced in Qt 4.6.

See also scale(), setTransformOriginPoint(), and Transformations Example.

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new void QtGui.IQGraphicsItem.SetSelected ( bool  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.

See also isSelected() and QGraphicsScene::selectedItems().

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new void QtGui.IQGraphicsItem.SetTransform ( QTransform  matrix,
bool  combine = false 
)

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.

The transformation matrix is combined with the item's rotation(), scale() and transformations() into a combined transformation that maps the item's coordinate system to its parent.

This function was introduced in Qt 4.3.

See also transform(), setRotation(), setScale(), setTransformOriginPoint(), The Graphics View Coordinate System, and Transformations.

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new void QtGui.IQGraphicsItem.SetTransformOriginPoint ( double  ax,
double  ay 
)

This is an overloaded function.

Sets the origin point for the transformation in item coordinates. This is equivalent to calling setTransformOriginPoint(QPointF(x, y)).

This function was introduced in Qt 4.6.

See also setTransformOriginPoint() and Transformations.

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new void QtGui.IQGraphicsItem.SetVisible ( bool  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.

See also isVisible(), show(), and hide().

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new void QtGui.IQGraphicsItem.Shear ( double  sh,
double  sv 
)

Use

setTransform(QTransform().shear(sh, sv), true);

instead.

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

See also setTransform() and transform().

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new void QtGui.IQGraphicsItem.Show ( )

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

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

See also hide() and setVisible().

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new void QtGui.IQGraphicsItem.StackBefore ( IQGraphicsItem  sibling)

Stacks this item before sibling, which must be a sibling item (i.e., the two items must share the same parent item, or must both be toplevel items). The sibling must have the same Z value as this item, otherwise calling this function will have no effect.

By default, all sibling items are stacked by insertion order (i.e., the first item you add is drawn before the next item you add). If two items' Z values are different, then the item with the highest Z value is drawn on top. When the Z values are the same, the insertion order will decide the stacking order.

This function was introduced in Qt 4.6.

See also setZValue(), ItemStacksBehindParent, and Sorting.

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new QGraphicsObject QtGui.IQGraphicsItem.ToGraphicsObject ( )

Return the graphics item cast to a QGraphicsObject, if the class is actually a graphics object, 0 otherwise.

This function was introduced in Qt 4.6.

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new void QtGui.IQGraphicsItem.Translate ( double  dx,
double  dy 
)

Use setPos() or setTransformOriginPoint() instead. For identical behavior, use

setTransform(QTransform::fromTranslate(dx, dy), true);

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.

See also setTransform() and transform().

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new void QtGui.IQGraphicsItem.UngrabKeyboard ( )

Releases the keyboard grab.

This function was introduced in Qt 4.4.

See also grabKeyboard() and ungrabMouse().

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new void QtGui.IQGraphicsItem.UngrabMouse ( )

Releases the mouse grab.

This function was introduced in Qt 4.4.

See also grabMouse() and ungrabKeyboard().

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new void QtGui.IQGraphicsItem.UnsetCursor ( )

Clears the cursor from this item.

See also hasCursor() and setCursor().

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new void QtGui.IQGraphicsItem.Update ( )

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.

See also paint() and boundingRect().

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new void QtGui.IQGraphicsItem.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.

See also paint() and boundingRect().

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

new void QtGui.IQGraphicsItem.Update ( double  x,
double  y,
double  width,
double  height 
)

This is an overloaded function.

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

Implemented in QtGui.QGraphicsObject, and QtGui.QGraphicsItem.

Property Documentation

System.Boolean QtGui.IQGraphicsItem.AcceptDrops
getset

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.

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.

Qt.MouseButton QtGui.IQGraphicsItem.AcceptedMouseButtons
getset

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.

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).

System.Boolean QtGui.IQGraphicsItem.AcceptHoverEvents
getset

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

This function was introduced in Qt 4.4.

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, 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.

A QGraphicsWidget with window decorations will accept hover events regardless of the value of acceptHoverEvents().

This function was introduced in Qt 4.4.

System.Boolean QtGui.IQGraphicsItem.AcceptsHoverEvents
getset

Call acceptHoverEvents() instead.

Use setAcceptHoverEvents(enabled) instead.

System.Boolean QtGui.IQGraphicsItem.AcceptTouchEvents
getset

Returns true if an item accepts touch events; otherwise, returns false. By default, items do not accept touch events.

This function was introduced in Qt 4.6.

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

This function was introduced in Qt 4.6.

QRectF QtGui.IQGraphicsItem.BoundingRect
get

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.

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);

}

See also boundingRegion(), shape(), contains(), The Graphics View Coordinate System, and prepareGeometryChange().

System.Double QtGui.IQGraphicsItem.BoundingRegionGranularity
getset

Returns the item's bounding region granularity; a value between and including 0 and 1. The default value is 0 (i.e., the lowest granularity, where the bounding region corresponds to the item's bounding rectangle).

This function was introduced in Qt 4.4.

Sets the bounding region granularity to granularity; a value between and including 0 and 1. The default value is 0 (i.e., the lowest granularity, where the bounding region corresponds to the item's bounding rectangle).

The granularity is used by boundingRegion() to calculate how fine the bounding region of the item should be. The highest achievable granularity is 1, where boundingRegion() will return the finest outline possible for the respective device (e.g., for a QGraphicsView viewport, this gives you a pixel-perfect bounding region). The lowest possible granularity is 0. The value of granularity describes the ratio between device resolution and the resolution of the bounding region (e.g., a value of 0.25 will provide a region where each chunk corresponds to 4x4 device units / pixels).

This function was introduced in Qt 4.4.

QGraphicsItem.CacheMode QtGui.IQGraphicsItem.cacheMode
getset

Returns the cache mode for this item. The default mode is NoCache (i.e., cache is disabled and all painting is immediate).

This function was introduced in Qt 4.4.

Sets the item's cache mode to mode.

The optional logicalCacheSize argument is used only by ItemCoordinateCache mode, and describes the resolution of the cache buffer; if logicalCacheSize is (100, 100), QGraphicsItem will fit the item into 100x100 pixels in graphics memory, regardless of the logical size of the item itself. By default QGraphicsItem uses the size of boundingRect(). For all other cache modes than ItemCoordinateCache, logicalCacheSize is ignored.

Caching can speed up rendering if your item spends a significant time redrawing itself. In some cases the cache can also slow down rendering, in particular when the item spends less time redrawing than QGraphicsItem spends redrawing from the cache. When enabled, the item's paint() function will be called only once for each call to update(); for any subsequent repaint requests, the Graphics View framework will redraw from the cache. This approach works particularly well with QGLWidget, which stores all the cache as OpenGL textures.

Be aware that QPixmapCache's cache limit may need to be changed to obtain optimal performance.

You can read more about the different cache modes in the CacheMode documentation.

This function was introduced in Qt 4.4.

System.Collections.Generic.List<IQGraphicsItem> QtGui.IQGraphicsItem.ChildItems
get

Returns a list of this item's children.

The items are sorted by stacking order. This takes into account both the items' insertion order and their Z-values.

This function was introduced in Qt 4.4.

See also setParentItem(), zValue(), and Sorting.

System.Collections.Generic.List<IQGraphicsItem> QtGui.IQGraphicsItem.Children
get

Use childItems() instead.

See also setParentItem().

QRectF QtGui.IQGraphicsItem.ChildrenBoundingRect
get

Returns the bounding rect of this item's descendants (i.e., its children, their children, etc.) in local coordinates. The rectangle will contain all descendants after they have been mapped to 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 descendants' 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 descendants.

See also boundingRect() and sceneBoundingRect().

QPainterPath QtGui.IQGraphicsItem.ClipPath
get

Returns this item's clip path, or an empty QPainterPath if this item is not clipped. The clip path constrains the item's appearance and interaction (i.e., restricts the area the item can draw, and it also restricts the area that the item receives events).

You can enable clipping by setting the ItemClipsToShape or ItemClipsChildrenToShape flags. The item's clip path is calculated by intersecting all clipping ancestors' shapes. If the item sets ItemClipsToShape, the final clip is intersected with the item's own shape.

Note: Clipping introduces a performance penalty for all items involved; you should generally avoid using clipping if you can (e.g., if your items always draw inside boundingRect() or shape() boundaries, clipping is not necessary).

This function was introduced in Qt 4.5.

See also isClipped(), shape(), and setFlags().

QCursor QtGui.IQGraphicsItem.Cursor
getset

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 cursor of the item beneath is used.

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.

System.Double QtGui.IQGraphicsItem.EffectiveOpacity
get

Returns this item's effective opacity, which is between 0.0 (transparent) and 1.0 (opaque). This value is a combination of this item's local opacity, and its parent and ancestors' opacities. The effective opacity decides how the item is rendered.

This function was introduced in Qt 4.5.

See also opacity(), setOpacity(), paint(), ItemIgnoresParentOpacity, and ItemDoesntPropagateOpacityToChildren.

System.Boolean QtGui.IQGraphicsItem.FiltersChildEvents
getset

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

The default value is false; child events are not filtered.

This function was introduced in Qt 4.6.

If enabled is true, this item is set to filter 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 function was introduced in Qt 4.6.

QGraphicsItem.GraphicsItemFlag QtGui.IQGraphicsItem.Flags
getset

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.

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. (QGraphicsWidget enables the ItemSendsGeometryChanges flag by default in order to track position changes.)

IQGraphicsItem QtGui.IQGraphicsItem.FocusProxy
getset

Returns this item's focus proxy, or 0 if this item has no focus proxy.

This function was introduced in Qt 4.6.

Sets the item's focus proxy to item.

If an item has a focus proxy, the focus proxy will receive input focus when the item gains input focus. The item itself will still have focus (i.e., hasFocus() will return true), but only the focus proxy will receive the keyboard input.

A focus proxy can itself have a focus proxy, and so on. In such case, keyboard input will be handled by the outermost focus proxy.

The focus proxy item must belong to the same scene as this item.

This function was introduced in Qt 4.6.

QGraphicsEffect QtGui.IQGraphicsItem.GraphicsEffect
getset

Returns a pointer to this item's effect if it has one; otherwise 0.

This function was introduced in Qt 4.6.

Sets effect as the item's effect. If there already is an effect installed on this item, QGraphicsItem will delete the existing effect before installing the new effect.

If effect is the installed on a different item, setGraphicsEffect() will remove the effect from the item and install it on this item.

QGraphicsItem takes ownership of effect.

Note: This function will apply the effect on itself and all its children.

This function was introduced in Qt 4.6.

QGraphicsItemGroup QtGui.IQGraphicsItem.Group
getset

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

System.Boolean QtGui.IQGraphicsItem.HandlesChildEvents
getset

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.

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.

System.Boolean QtGui.IQGraphicsItem.HasCursor
get

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.

See also unsetCursor().

System.Boolean QtGui.IQGraphicsItem.HasFocus
get

Returns true if this item is active, and it or its focus proxy has keyboard input focus; otherwise, returns false.

See also focusItem(), setFocus(), QGraphicsScene::setFocusItem(), and isActive().

Qt.InputMethodHint QtGui.IQGraphicsItem.InputMethodHints
getset

Returns the current input method hints of this item.

Input method hints are only relevant for input items. The hints are used by the input method to indicate how it should operate. For example, if the Qt::ImhNumbersOnly flag is set, the input method may change its visual components to reflect that only numbers can be entered.

The effect may vary between input method implementations.

This function was introduced in Qt 4.6.

Sets the current input method hints of this item to hints.

This function was introduced in Qt 4.6.

System.Boolean QtGui.IQGraphicsItem.IsActive
get

Returns true if this item is active; otherwise returns false.

An item can only be active if the scene is active. An item is active if it is, or is a descendent of, an active panel. Items in non-active panels are not active.

Items that are not part of a panel follow scene activation when the scene has no active panel.

Only active items can gain input focus.

This function was introduced in Qt 4.6.

See also QGraphicsScene::isActive(), QGraphicsScene::activePanel(), panel(), and isPanel().

System.Boolean QtGui.IQGraphicsItem.IsClipped
get

Returns true if this item is clipped. An item is clipped if it has either set the ItemClipsToShape flag, or if it or any of its ancestors has set the ItemClipsChildrenToShape flag.

Clipping affects the item's appearance (i.e., painting), as well as mouse and hover event delivery.

See also clipPath(), shape(), and setFlags().

System.Boolean QtGui.IQGraphicsItem.IsEnabled
get

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

See also setEnabled().

System.Boolean QtGui.IQGraphicsItem.IsPanel
get

Returns true if the item is a panel; otherwise returns false.

This function was introduced in Qt 4.6.

See also QGraphicsItem::panel() and ItemIsPanel.

System.Boolean QtGui.IQGraphicsItem.IsSelected
get

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.

See also setSelected() and QGraphicsScene::setSelectionArea().

System.Boolean QtGui.IQGraphicsItem.IsUnderMouse
get

Returns true if this item is currently under the mouse cursor in one of the views; otherwise, false is returned.

This function was introduced in Qt 4,4.

See also QGraphicsScene::views() and QCursor::pos().

System.Boolean QtGui.IQGraphicsItem.IsVisible
get

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.

See also setVisible().

System.Boolean QtGui.IQGraphicsItem.IsWidget
get

Returns true if this item is a widget (i.e., QGraphicsWidget); otherwise, returns false.

This function was introduced in Qt 4.4.

System.Boolean QtGui.IQGraphicsItem.IsWindow
get

Returns true if the item is a QGraphicsWidget window, otherwise returns false.

This function was introduced in Qt 4.4.

See also QGraphicsWidget::windowFlags().

QMatrix QtGui.IQGraphicsItem.Matrix
get

Returns the item's affine transformation matrix. This is a subset or the item's full transformation matrix, and might not represent the item's full transformation.

Use transform() instead.

See also setMatrix(), setTransform(), and sceneTransform().

System.Double QtGui.IQGraphicsItem.Opacity
getset

Returns this item's local opacity, which is between 0.0 (transparent) and 1.0 (opaque). This value is combined with parent and ancestor values into the effectiveOpacity(). The effective opacity decides how the item is rendered.

The opacity property decides the state of the painter passed to the paint() function. If the item is cached, i.e., ItemCoordinateCache or DeviceCoordinateCache, the effective property will be applied to the item's cache as it is rendered.

The default opacity is 1.0; fully opaque.

This function was introduced in Qt 4.5.

Sets this item's local opacity, between 0.0 (transparent) and 1.0 (opaque). The item's local opacity is combined with parent and ancestor opacities into the effectiveOpacity().

By default, opacity propagates from parent to child, so if a parent's opacity is 0.5 and the child is also 0.5, the child's effective opacity will be 0.25.

The opacity property decides the state of the painter passed to the paint() function. If the item is cached, i.e., ItemCoordinateCache or DeviceCoordinateCache, the effective property will be applied to the item's cache as it is rendered.

There are two item flags that affect how the item's opacity is combined with the parent: ItemIgnoresParentOpacity and ItemDoesntPropagateOpacityToChildren.

This function was introduced in Qt 4.5.

QPainterPath QtGui.IQGraphicsItem.OpaqueArea
get

This virtual function returns a shape representing the area where this item is opaque. An area is opaque if it is filled using an opaque brush or color (i.e., not transparent).

This function is used by isObscuredBy(), which is called by underlying items to determine if they are obscured by this item.

The default implementation returns an empty QPainterPath, indicating that this item is completely transparent and does not obscure any other items.

See also isObscuredBy(), isObscured(), and shape().

IQGraphicsItem QtGui.IQGraphicsItem.Panel
get

Returns the item's panel, or 0 if this item does not have a panel. If the item is a panel, it will return itself. Otherwise it will return the closest ancestor that is a panel.

This function was introduced in Qt 4.6.

See also isPanel() and ItemIsPanel.

QGraphicsItem.PanelModality QtGui.IQGraphicsItem.panelModality
getset

Returns the modality for this item.

This function was introduced in Qt 4.6.

Sets the modality for this item to panelModality.

Changing the modality of a visible item takes effect immediately.

This function was introduced in Qt 4.6.

IQGraphicsItem QtGui.IQGraphicsItem.ParentItem
getset

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

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

Note that this implicitly adds this graphics item to the scene of the parent. You should not add the item to the scene yourself.

Calling this function on an item that is an ancestor of newParent have undefined behaviour.

QGraphicsObject QtGui.IQGraphicsItem.ParentObject
get

Returns a pointer to the item's parent, cast to a QGraphicsObject. returns 0 if the parent item is not a QGraphicsObject.

This function was introduced in Qt 4.6.

See also parentItem() and childItems().

QGraphicsWidget QtGui.IQGraphicsItem.ParentWidget
get

Returns a pointer to the item's parent widget. The item's parent widget is the closest parent item that is a widget.

This function was introduced in Qt 4.4.

See also parentItem() and childItems().

QPointF QtGui.IQGraphicsItem.Pos
getset

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.

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.

System.Double QtGui.IQGraphicsItem.Rotation
getset

Returns the clockwise rotation, in degrees, around the Z axis. The default value is 0 (i.e., the item is not rotated).

The rotation is combined with the item's scale(), transform() and transformations() to map the item's coordinate system to the parent item.

This function was introduced in Qt 4.6.

Sets the clockwise rotation angle, in degrees, around the Z axis. The default value is 0 (i.e., the item is not rotated). Assigning a negative value will rotate the item counter-clockwise. Normally the rotation angle is in the range (-360, 360), but it's also possible to assign values outside of this range (e.g., a rotation of 370 degrees is the same as a rotation of 10 degrees).

The item is rotated around its transform origin point, which by default is (0, 0). You can select a different transformation origin by calling setTransformOriginPoint().

The rotation is combined with the item's scale(), transform() and transformations() to map the item's coordinate system to the parent item.

This function was introduced in Qt 4.6.

QGraphicsScene QtGui.IQGraphicsItem.Scene
get

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().

QRectF QtGui.IQGraphicsItem.SceneBoundingRect
get

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

See also boundingRect() and The Graphics View Coordinate System.

QMatrix QtGui.IQGraphicsItem.SceneMatrix
get

Use sceneTransform() instead.

See also transform(), setTransform(), scenePos(), and The Graphics View Coordinate System.

QPointF QtGui.IQGraphicsItem.ScenePos
get

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

See also pos(), sceneTransform(), and The Graphics View Coordinate System.

QTransform QtGui.IQGraphicsItem.SceneTransform
get

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, and all the transfomation properties.

This function was introduced in Qt 4.3.

See also transform(), setTransform(), scenePos(), The Graphics View Coordinate System, and Transformations.

QPainterPath QtGui.IQGraphicsItem.Shape
get

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;

}

The outline of a shape can vary depending on the width and style of the pen used when drawing. If you want to include this outline in the item's shape, you can create a shape from the stroke using QPainterPathStroker.

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

See also boundingRect(), contains(), prepareGeometryChange(), and QPainterPathStroker.

System.String QtGui.IQGraphicsItem.ToolTip
getset

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

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

IQGraphicsItem QtGui.IQGraphicsItem.TopLevelItem
get

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).

See also parentItem().

QGraphicsWidget QtGui.IQGraphicsItem.TopLevelWidget
get

Returns a pointer to the item's top level widget (i.e., the item's ancestor whose parent is 0, or whose parent is not a widget), or 0 if this item does not have a top level widget. If the item is its own top level widget, this function returns a pointer to the item itself.

This function was introduced in Qt 4.4.

QTransform QtGui.IQGraphicsItem.Transform
get

Returns this item's transformation matrix.

The transformation matrix is combined with the item's rotation(), scale() and transformations() into a combined transformations for the item.

The default transformation matrix is an identity matrix.

This function was introduced in Qt 4.3.

See also setTransform() and sceneTransform().

System.Collections.Generic.List<QGraphicsTransform> QtGui.IQGraphicsItem.Transformations
getset

Returns a list of graphics transforms that currently apply to this item.

QGraphicsTransform is for applying and controlling a chain of individual transformation operations on an item. It's particularly useful in animations, where each transform operation needs to be interpolated independently, or differently.

The transformations are combined with the item's rotation(), scale() and transform() to map the item's coordinate system to the parent item.

This function was introduced in Qt 4.6.

Sets a list of graphics transformations (QGraphicsTransform) that currently apply to this item.

If all you want is to rotate or scale an item, you should call setRotation() or setScale() instead. If you want to set an arbitrary transformation on an item, you can call setTransform().

QGraphicsTransform is for applying and controlling a chain of individual transformation operations on an item. It's particularly useful in animations, where each transform operation needs to be interpolated independently, or differently.

The transformations are combined with the item's rotation(), scale() and transform() to map the item's coordinate system to the parent item.

This function was introduced in Qt 4.6.

QPointF QtGui.IQGraphicsItem.TransformOriginPoint
getset

Returns the origin point for the transformation in item coordinates.

The default is QPointF(0,0).

This function was introduced in Qt 4.6.

Sets the origin point for the transformation in item coordinates.

This function was introduced in Qt 4.6.

System.Int32 QtGui.IQGraphicsItem.Type
get

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.

The default implementation (in QGraphicsItem) returns UserType.

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

For example:

class CustomItem : public QGraphicsItem

{

...

enum { Type = UserType + 1 };

int type() const

{

// Enable the use of qgraphicsitem_cast with this item.

return Type;

}

...

};

See also UserType.

QGraphicsWidget QtGui.IQGraphicsItem.Window
get

Returns the item's window, or 0 if this item does not have a window. If the item is a window, it will return itself. Otherwise it will return the closest ancestor that is a window.

This function was introduced in Qt 4.4.

See also QGraphicsWidget::isWindow().

System.Double QtGui.IQGraphicsItem.X
getset

This convenience function is equivalent to calling pos().x().

Set's the x coordinate of the item's position. Equivalent to calling setPos(x, y()).

This function was introduced in Qt 4.6.

System.Double QtGui.IQGraphicsItem.Y
getset

This convenience function is equivalent to calling pos().y().

Set's the y coordinate of the item's position. Equivalent to calling setPos(x(), y).

This function was introduced in Qt 4.6.

System.Double QtGui.IQGraphicsItem.ZValue
getset

Returns the Z-value of the item. The Z-value affects the stacking order of sibling (neighboring) items.

The default Z-value is 0.

Sets the Z-value of the item to z. The Z value decides the stacking order of sibling (neighboring) items. A sibling item of high Z value will always be drawn on top of another sibling item with a lower Z value.

If you restore the Z value, the item's insertion order will decide its stacking order.

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

The default Z-value is 0.