Typedef for QFlags<CacheModeFlag>. Refer to QGraphicsView::CacheModeFlag for documentation.

Typedef for QFlags<OptimizationFlag>. Refer to QGraphicsView::OptimizationFlag for documentation.

This enum describes the flags that you can set for a QGraphicsView's cache mode.

See also

cacheMode

This enum describes the default action for the view when pressing and dragging the mouse over the viewport.

See also

dragMode, QGraphicsScene::setSelectionArea()

This enum describes flags which can enabled to improve rendering performance. By default none of these flags are set. Setting a flag usually imposes a side effect which can vary between paint devices and platforms.

This enums describe the possible anchors that QGraphicsView can use when the user resizes the view or when the view is transformed.

See also

resizeAnchor, transformationAnchor

This enum describes how QGraphicsView updates its viewport when the scene contents change or are exposed.

See also

viewportUpdateMode

Constructs a QGraphicsView. The parent is passed to the QWidget constructor.

Constructs a QGraphicsView and sets the visualized scene to scene. The parent is passed to the QWidget constructor.

Destroys the QGraphicsView object.

Returns the value of the QGraphicsView::alignment property.

Returns the value of the backgroundBrush property.

Returns the value of the cacheMode property.

Scrolls the contents of the viewport to ensure that item is centered in the view.

See also

ensureVisible()

Scrolls the contents of the viewport to ensure the scene coordinate pos is centered in the view. Because pos is a floating point coordinate and the scroll bars operate on integer coordinates, the centering is only an approximation.

If the item is close to or outside the border it will be visible in the view but not centered.

See also

ensureVisible()

Equivalent to calling centerOn(QPointF(x, y)).

Reimplemented from QWidget::contextMenuEvent()

Reimplemented from QWidget::dragEnterEvent()

Reimplemented from QWidget::dragLeaveEvent()

Returns the value of the dragMode property.

Reimplemented from QWidget::dragMoveEvent()

Draws the background of the scene using painter, before any items and the foreground are drawn. Reimplement this method to provide a custom background for this view. If all you want is to define a color, texture or gradient for the background call setBackgroundBrush().

All painting is done in scene coordinates. The value for rect is the exposed rectangle. The default implementation fills rect using the view's backgroundBrush. If no brush is defined the drawBackground() method for the scene is called.

See also

drawForeground(), QGraphicsScene::drawBackground()

Draws the foreground of the scene using painter, after the background and all items are drawn. Reimplement this method to provide a custom foreground for this view. If all you want is to define a color, texture or gradient for the foreground call setForegroundBrush().

All painting is done in scene coordinates. The value for rect is the exposed rectangle. The default implementation fills rect using the view's foregroundBrush. If no brush is defined drawForeground() method for the scene is called.

See also

drawBackground(), QGraphicsScene::drawForeground()

Deprecated:

Not recommend for application code.

Draws the items in the scene using painter after the background and before the foreground are drawn. The numItems is the number of items in the given items and options. The value for options is a list of styleoptions with one for each item.

Reimplement this method to provide custom item drawing for this view. The default implementation calls the scene's drawItems() method. This method is not called unless the QGraphicsView::IndirectPainting flag is given as an Optimization flag.

See also

drawForeground(), drawBackground(), QGraphicsScene::drawItems()

Reimplemented from QWidget::dropEvent()

Scrolls the contents of the viewport so the center of item is visible, with margins specified in pixels by xmargin and ymargin. If the specified point can not be reached, the contents are scrolled to the nearest valid position. The default value for both margins is 50 pixels.

See also

centerOn()

Scrolls the contents of the viewport so the scene rectangle rect is visible, with margins specified in pixels by xmargin and ymargin. If the specified rect can not be reached the contents are scrolled to the nearest valid position. The default value for both margins is 50 pixels.

See also

centerOn()

Equivalent to calling ensureVisible(QRectF(x, y, width, height), xmargin, ymargin).

Reimplemented from QAbstractScollArea::event()

Ensures item fits exactly inside the view by scaling the view according to mode.

See also

ensureVisible(), centerOn()

Scales the view matrix and scrolls the scroll bars to ensure that the scene rect fits inside the viewport. The given rect must be inside the scene rectangle otherwise this method can not guarantee the entire rectangle will be visible. This method does not change the current rotation, translation, or shear. The view is scaled according to mode. The rect will be centered in the view if it does not fit exactly. If rect is empty or if the viewport is too small this method will do nothing.

It is common to call this method from inside a reimplementation of resizeEvent() to ensure the entire scene or parts of the scene is scaled to fit the new size. However, this can lead to infinite resize recursion when the transformation toggles the state of the scrollbars. You can set the scrollbar policies to always on or always off to prevent this from happening.

See also

setTransform(), ensureVisible(), centerOn(), horizontalScrollBarPolicy(), verticalScrollBarPolicy()

Equivalent to calling fitInView(QRectF(x, y, width,height), mode).

See also

ensureVisible(), centerOn()

Reimplemented from QWidget::focusInEvent()

Reimplemented from QWidget::focusNextPrevChild()

Reimplemented from QWidget::focusOutEvent()

Returns the value of the foregroundBrush property.

Reimplemented from QWidget::inputMethodEvent()

Reimplemented from QWidget::inputMethodQuery()

Invalidates and schedules a redraw of layers inside rect. The given rect is in scene coordinates. Call this method to notify QGraphicsView of changes to the background or the foreground of the scene.

QGraphicsView only supports caching the background layer. This method is equivalent to calling update() if any layer other than QGraphicsScene::BackgroundLayer is passed.

See also

QGraphicsScene::invalidate(), update(), QGraphicsView::CacheModeFlag

Returns the value of the QGraphicsView::interactive property.

Returns true if the view is transformed which occurs when a transform has been assigned or the scrollbars are adjusted.

See also

setTransform(), horizontalScrollBar(), verticalScrollBar()

Returns the item located at pos. The position is in viewport coordinates. If there are several items at this position this method returns the item in front.

See also

items(), Sorting

Equivalent to calling itemAt(QPoint(x, y)).

Returns a sorted list of all the items in the current scene. The first element is the front item.

See also

QGraphicsScene::items(), Sorting

Returns a sorted list of all the items matching the given path and mode. The value for path is in viewport coordinates. The first element is the front item. The default value for mode is Qt::IntersectsItemShape where all items whose exact shape intersects with or is contained by path are returned.

See also

itemAt(), items(), mapToScene(), Sorting

Returns a sorted list of items at pos. The position is in viewport coordinates. The first element is the front item.

See also

QGraphicsScene::items(), Sorting

Returns a sorted list of all the items matching the given polygon and mode. The value for polygon is in viewport coordinates. The first element is the front item. The default value for mode is Qt::IntersectsItemShape where all items whose exact shape intersects with or is contained by polygon are returned.

See also

itemAt(), items(), mapToScene(), Sorting

Returns a sorted list of all the items matching the given rect and mode. The value for rect is in viewport coordinates. The first element is the front item. The default value for mode is Qt::IntersectsItemShape where all items whose exact shape intersects with or is contained by rect are returned.

See also

itemAt(), items(), mapToScene(), Sorting

Equivalent to calling items(QPoint(x, y)).

Equivalent to calling items(QRectF(x, y, width, height), mode).

Reimplemented from QWidget::keyPressEvent()

Reimplemented from QWidget::keyReleaseEvent()

Converts the given path from scene coordinates to viewport coordinates.

See also

mapToScene()

Converts the given point from scene coordinates to viewport coordinates.

See also

mapToScene()

Converts the given polygon from scene coordinates to viewport coordinates.

See also

mapToScene()

Converts the given rect from scene coordinates to viewport coordinates.

See also

mapToScene()

Equivalent to calling mapFromScene(QPointF(x, y)).

Equivalent to calling mapFromScene(QRectF(x, y, width, height)).

Converts the given path from viewport coordinates to scene coordinates.

See also

mapFromScene()

Converts the given point from viewport coordinates to scene coordinates.

It can be useful to map the entire rectangle covered by the pixel at the given point instead of the point itself. To do this call mapToScene(QRect(point, QSize(2, 2))).

See also

mapFromScene()

Converts the given polygon from viewport coordinates to scene coordinates.

See also

mapFromScene()

Converts the given rect from viewport coordinates to scene coordinates.

See also

mapFromScene()

Equivalent to calling mapToScene(QPoint(x, y)).

Equivalent to calling mapToScene(QRect(x, y, width, height).

Returns the current transformation matrix for the view. If no current transformation is set the identity matrix is returned.

See also

setMatrix(), transform(), rotate(), scale(), shear(), translate()

Reimplemented from QWidget::mouseDoubleClickEvent()

Reimplemented from QWidget::mouseMoveEvent()

Reimplemented from QWidget::mousePressEvent()

Reimplemented from QWidget::mouseReleaseEvent()

Returns the value of the optimizationFlags property.

Reimplemented from QWidget::paintEvent()

Renders the source rectangle which is in view coordinates into the target rectangle, which is in paint device coordinates, using painter. This method is useful for rendering the contents of the view onto a paint device, such as a QImage or for printing to a QPrinter.

If source is a null rectangle this method will call rect() to determine what to render. If the target is a null rectangle the full dimensions of the QPainter device will be used. The source rectangle contents will be transformed according to mode to fit into the target rectangle. By default, the aspect ratio is kept and source is scaled to fit in target.

See also

QGraphicsScene::render()

Returns the value of the renderHints property.

Clears all cached content. If the current cache mode is CacheNone then this method does nothing. This method is called automatically when the backgroundBrush or QGraphicsScene::backgroundBrush properties change. Only call this method if you have reimplemented QGraphicsScene::drawBackground() or QGraphicsView::drawBackground() to draw a custom background and need to trigger a full redraw.

See also

cacheMode()

Resets the view transformation matrix to the identity matrix.

See also

resetTransform()

Resets the view transformation matrix to the identity matrix.

See also

transform(), setTransform()

Returns the value of the resizeAnchor property.

Reimplemented from QWidget::resizeEvent()

Rotates the current view transformation angle degrees clockwise.

See also

setTransform(), transform(), scale(), shear(), translate()

This signal is emitted when the rubber band rectangle is changed. The viewport is specified by viewportRect. The drag start position and drag end position are provided in scene coordinates with fromScenePoint and toScenePoint.

When a rubber band selection ends this signal will be emitted and all of the values will be null.

See also

rubberBandRect()

This method returns the current rubber band area in viewport coordinates if the user is currently doing an item selection with the rubber band. When the user is not using the rubber band this method returns a null QRectF. Part of this QRect can be outside the visual viewport or contain negative values.

See also

rubberBandSelectionMode, rubberBandChanged()

Returns the value of the rubberBandSelectionMode property.

Scales the current view transformation by (sx, sy).

See also

setTransform(), transform(), rotate(), shear(), translate()

Returns a pointer to the scene which is currently displayed in the view. If no scene is currently displayed a nullptr is returned.

See also

setScene()

Returns the value of the sceneRect property.

Reimplemented from QAbstractScrollArea::scrollContentsBy()

Sets the value of the QGraphicsView::alignment property to alignment.

Sets the value of the backgroundBrush property to brush.

Sets the value of the cacheMode property to mode.

Sets the value of the dragMode property to mode.

Sets the value of the foregroundBrush property to brush.

Sets the value of the QGraphicsView::interactive property to allowed.

Sets the view's current transformation to matrix. If combine is true then the given matrix is combined with the current matrix, otherwise matrix replaces the current matrix.

The transformation matrix is used to transform the scene into view coordinates. The default transformation uses the identity matrix which means one pixel in the view is one unit in the scene. To simplify interaction with items using a transformed view, QGraphicsView provides mapToScene() and mapFromScene() methods which translate between scene and view coordinates.

See also

matrix(), setTransform(), rotate(), scale(), shear(), translate()

Enables flag if enabled is true, otherwise disables flag.

See also

optimizationFlags

Sets the value of the optimizationFlags property to flags.

If enabled is true the render hint is enabled, otherwise it is disabled.

See also

renderHints

Sets the value of the renderHints property to hints.

Sets the value of the resizeAnchor property to anchor.

Sets the value of the rubberBandSelectionMode property to mode.

Sets the current scene to the given scene. If the scene is being displayed this method does nothing. When a scene is set on a view the QGraphicsScene::changed() signal is automatically connected to this view's updateScene() slot and the view's scroll bars are adjusted to fit the size of the scene.

See also

scene()

Sets the value of the sceneRect property to rect.

Sets the value of the sceneRect property to (x, y, width, height).

Sets the view's current transformation to matrix. If combine is true then the given matrix is combined with the current matrix, otherwise matrix replaces the current matrix.

The transformation matrix is used to transform the scene into view coordinates. The default transformation uses the identity matrix which means one pixel in the view is one unit in the scene. To simplify interaction with items using a transformed view, QGraphicsView provides mapToSceene() and mapFromScene() methods which translate between scene and view coordinates.

See also

transform(), rotate(), scale(), shear(), translate()

Sets the value of the transformationAnchor property to anchor.

This slot is called by QAbstractScrollArea after setViewport() has been called. Reimplement this method in a subclass of QGraphicsView to initialize the new viewport widget before it is used.

See also

setViewport()

Sets the value of the viewportUpdateMode property to mode.

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

See also

setTransform(), transform(), rotate(), scale(), translate()

Reimplemented from QWidget::showEvent()

Reimplemented from QWidget::sizeHint()

Returns the current transformation matrix for the view. If no transformation is set the identity matrix is returned.

See also

setTransform(), rotate(), scale(), shear(), translate()

Returns the value of the transformationAnchor property.

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

See also

setTransform(), transform(), rotate(), shear()

Schedules an update of the scene rectangles rects.

See also

QGraphicsScene::changed()

Notifies QGraphicsView the scene's rectangle has changed. The given rect is the new scene rectangle. If the view already has an explicitly set scene rectangle this method does nothing.

See also

sceneRect, QGraphicsScene::sceneRectChanged()

Reimplemented from QAbstractScrollArea::viewportEvent()

Returns a matrix which maps viewport coordinates to scene coordinates.

See also

mapToScene(), mapFromScene()

Returns the value of the viewportUpdateMode property.

Reimplemented from QWidget::wheelEvent()

This property holds the alignment of the scene in the view when the entire scene is visible.

If the entire scene is visible in the view the alignment will determine where the scene will be rendered in the view. For example, if the alignment is Qt::AlignCenter the scene will be centered in the view and if the alignment is (Qt::AlignLeft | Qt::AlignTop) the scene will be rendered in the top-left corner of the view.

This property holds the background brush of the scene. This property sets the background brush for the scene in this view. It is used to override the scene's own background and defines the behavior of drawBackground(). To provide custom background drawing for this view reimplement drawBackground().

By default, this property contains a brush with the Qt::NoBrush pattern.

See also

QGraphicsScene::backgroundBrush, foregroundBrush

This property holds which parts of the view are cached. QGraphicsView can cache pre-rendered content in a QPixmap, which is then drawn onto the viewport. The purpose of such caching is to speed up the total rendering time for areas which are slow to render. Texture, gradient, and alpha blended backgrounds, can be slow to render, especially with a transformed view. The CacheBackground flag enables caching of the view's background.

The cache is invalidated every time the view is transformed. When scrolling, only partial invalidation is required. By default nothing is cached.

See also

resetCachedContent(), QPixmapCache

This property holds the behavior for dragging the mouse over the scene while the left mouse button is pressed. This property defines what should happen when the user clicks on the scene background and drags the mouse along the background. The default value NoDrag does nothing.

This dragMode only affects mouse clicks that are not handled by any item. You can define a custom behavior by creating a subclass of QGraphicsView and reimplementing mouseMoveEvent().

This property holds the foreground brush of the scene. This property sets the foreground brush for the scene in this view. It is used to override the foreground and defines the behavior of drawForeground(). To customize the foreground drawing for this view reimplement drawForeground(). By default, this property contains a brush with the Qt::NoBrush pattern.

See also

QGraphicsScene::foregroundBrush, backgroundBrush

This property holds whether the view allowed scene interaction. If enabled the view is set to allow scene interaction. Otherwise, this view will not allow interaction and any mouse or key events are ignored. By default, this property is true.

This property holds flags which are used to optimize performance. QGraphicsView uses clipping, extra bounding rectangle adjustments, and certain other strategies to improve rendering quality and performance for the common case graphics scene. Depending on the target platform the scene and the viewport, some of these strategies operations can degrade performance and should be turned off. By default, no optimization flags are enabled.

See also

setOptimizationFlag(), OptimizationFlags