QGraphicsView¶

The QGraphicsView class provides a widget for displaying the contents of a QGraphicsScene . More…

Inherited by: QtCharts.QChartView

Synopsis¶

Functions¶

def alignment ()
def backgroundBrush ()
def cacheMode ()
def centerOn (item)
def centerOn (pos)
def centerOn (x, y)
def dragMode ()
def ensureVisible (item[, xmargin=50[, ymargin=50]])
def ensureVisible (rect[, xmargin=50[, ymargin=50]])
def ensureVisible (x, y, w, h[, xmargin=50[, ymargin=50]])
def fitInView (item[, aspectRadioMode=Qt.IgnoreAspectRatio])
def fitInView (rect[, aspectRadioMode=Qt.IgnoreAspectRatio])
def fitInView (x, y, w, h[, aspectRadioMode=Qt.IgnoreAspectRatio])
def foregroundBrush ()
def isInteractive ()
def isTransformed ()
def itemAt (pos)
def itemAt (x, y)
def items ()
def items (path[, mode=Qt.IntersectsItemShape])
def items (polygon[, mode=Qt.IntersectsItemShape])
def items (pos)
def items (rect[, mode=Qt.IntersectsItemShape])
def items (x, y)
def items (x, y, w, h[, mode=Qt.IntersectsItemShape])
def mapFromScene (path)
def mapFromScene (point)
def mapFromScene (polygon)
def mapFromScene (rect)
def mapFromScene (x, y)
def mapFromScene (x, y, w, h)
def mapToScene (path)
def mapToScene (point)
def mapToScene (polygon)
def mapToScene (rect)
def mapToScene (x, y)
def mapToScene (x, y, w, h)
def matrix ()
def optimizationFlags ()
def render (painter[, target=QRectF()[, source=QRect()[, aspectRatioMode=Qt.KeepAspectRatio]]])
def renderHints ()
def resetCachedContent ()
def resetMatrix ()
def resetTransform ()
def resizeAnchor ()
def rotate (angle)
def rubberBandRect ()
def rubberBandSelectionMode ()
def scale (sx, sy)
def scene ()
def sceneRect ()
def setAlignment (alignment)
def setBackgroundBrush (brush)
def setCacheMode (mode)
def setDragMode (mode)
def setForegroundBrush (brush)
def setInteractive (allowed)
def setMatrix (matrix[, combine=false])
def setOptimizationFlag (flag[, enabled=true])
def setOptimizationFlags (flags)
def setRenderHint (hint[, enabled=true])
def setRenderHints (hints)
def setResizeAnchor (anchor)
def setRubberBandSelectionMode (mode)
def setScene (scene)
def setSceneRect (rect)
def setSceneRect (x, y, w, h)
def setTransform (matrix[, combine=false])
def setTransformationAnchor (anchor)
def setViewportUpdateMode (mode)
def shear (sh, sv)
def transform ()
def transformationAnchor ()
def translate (dx, dy)
def viewportTransform ()
def viewportUpdateMode ()

Virtual functions¶

def drawBackground (painter, rect)
def drawForeground (painter, rect)
def drawItems (painter, items, options)

Slots¶

def invalidateScene ([rect=QRectF()[, layers=QGraphicsScene.AllLayers]])
def updateScene (rects)
def updateSceneRect (rect)

Signals¶

def rubberBandChanged (viewportRect, fromScenePoint, toScenePoint)

Detailed Description¶

QGraphicsView visualizes the contents of a QGraphicsScene in a scrollable viewport. To create a scene with geometrical items, see QGraphicsScene ‘s documentation. QGraphicsView is part of the Graphics View Framework .

To visualize a scene, you start by constructing a QGraphicsView object, passing the address of the scene you want to visualize to QGraphicsView ‘s constructor. Alternatively, you can call setScene() to set the scene at a later point. After you call show() , the view will by default scroll to the center of the scene and display any items that are visible at this point. For example:
scene = QGraphicsScene()
scene.addText("Hello, world!")

view = QGraphicsView(scene)
view.show()
You can explicitly scroll to any position on the scene by using the scroll bars, or by calling centerOn() . By passing a point to centerOn() , QGraphicsView will scroll its viewport to ensure that the point is centered in the view. An overload is provided for scrolling to a QGraphicsItem , in which case QGraphicsView will see to that the center of the item is centered in the view. If all you want is to ensure that a certain area is visible, (but not necessarily centered,) you can call ensureVisible() instead.

QGraphicsView can be used to visualize a whole scene, or only parts of it. The visualized area is by default detected automatically when the view is displayed for the first time (by calling itemsBoundingRect() ). To set the visualized area rectangle yourself, you can call setSceneRect() . This will adjust the scroll bars’ ranges appropriately. Note that although the scene supports a virtually unlimited size, the range of the scroll bars will never exceed the range of an integer (INT_MIN, INT_MAX).

QGraphicsView visualizes the scene by calling render() . By default, the items are drawn onto the viewport by using a regular QPainter , and using default render hints. To change the default render hints that QGraphicsView passes to QPainter when painting items, you can call setRenderHints() .

By default, QGraphicsView provides a regular QWidget for the viewport widget. You can access this widget by calling viewport() , or you can replace it by calling setViewport() . To render using OpenGL, simply call setViewport (new QGLWidget ). QGraphicsView takes ownership of the viewport widget.

QGraphicsView supports affine transformations, using QTransform . You can either pass a matrix to setTransform() , or you can call one of the convenience functions rotate() , scale() , translate() or shear() . The most two common transformations are scaling, which is used to implement zooming, and rotation. QGraphicsView keeps the center of the view fixed during a transformation. Because of the scene alignment (setAligment()), translating the view will have no visual impact.

You can interact with the items on the scene by using the mouse and keyboard. QGraphicsView translates the mouse and key events into scene events, (events that inherit QGraphicsSceneEvent ,), and forward them to the visualized scene. In the end, it’s the individual item that handles the events and reacts to them. For example, if you click on a selectable item, the item will typically let the scene know that it has been selected, and it will also redraw itself to display a selection rectangle. Similiary, if you click and drag the mouse to move a movable item, it’s the item that handles the mouse moves and moves itself. Item interaction is enabled by default, and you can toggle it by calling setInteractive() .

You can also provide your own custom scene interaction, by creating a subclass of QGraphicsView , and reimplementing the mouse and key event handlers. To simplify how you programmatically interact with items in the view, QGraphicsView provides the mapping functions mapToScene() and mapFromScene() , and the item accessors items() and itemAt() . These functions allow you to map points, rectangles, polygons and paths between view coordinates and scene coordinates, and to find items on the scene using view coordinates.

See also

QGraphicsScene QGraphicsItem QGraphicsSceneEvent

class QGraphicsView(scene[, parent=None])¶

QGraphicsView([parent=None])

param parent

QWidget

param scene

QGraphicsScene

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

Constructs a QGraphicsView . parent is passed to QWidget ‘s constructor.

PySide2.QtWidgets.QGraphicsView.ViewportAnchor¶

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

Constant	Description
QGraphicsView.NoAnchor	No anchor, i.e. the view leaves the scene’s position unchanged.
QGraphicsView.AnchorViewCenter	The scene point at the center of the view is used as the anchor.
QGraphicsView.AnchorUnderMouse	The point under the mouse is used as the anchor.

See also

resizeAnchor transformationAnchor

PySide2.QtWidgets.QGraphicsView.CacheModeFlag¶

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

Constant	Description
QGraphicsView.CacheNone	All painting is done directly onto the viewport.
QGraphicsView.CacheBackground	The background is cached. This affects both custom backgrounds, and backgrounds based on the `backgroundBrush` property. When this flag is enabled, `QGraphicsView` will allocate one pixmap with the full size of the viewport.

See also

cacheMode

PySide2.QtWidgets.QGraphicsView.DragMode¶

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

Constant	Description
QGraphicsView.NoDrag	Nothing happens; the mouse event is ignored.
QGraphicsView.ScrollHandDrag	The cursor changes into a pointing hand, and dragging the mouse around will scroll the scrolbars. This mode works both in `interactive` and non-interactive mode.
QGraphicsView.RubberBandDrag	A rubber band will appear. Dragging the mouse will set the rubber band geometry, and all items covered by the rubber band are selected. This mode is disabled for non-interactive views.

See also

dragMode setSelectionArea()

PySide2.QtWidgets.QGraphicsView.ViewportUpdateMode¶

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

Constant	Description
QGraphicsView.FullViewportUpdate	When any visible part of the scene changes or is reexposed, `QGraphicsView` will update the entire viewport. This approach is fastest when `QGraphicsView` spends more time figuring out what to draw than it would spend drawing (e.g., when very many small items are repeatedly updated). This is the preferred update mode for viewports that do not support partial updates, such as `QGLWidget` , and for viewports that need to disable scroll optimization.
QGraphicsView.MinimalViewportUpdate	`QGraphicsView` will determine the minimal viewport region that requires a redraw, minimizing the time spent drawing by avoiding a redraw of areas that have not changed. This is `QGraphicsView` ‘s default mode. Although this approach provides the best performance in general, if there are many small visible changes on the scene, `QGraphicsView` might end up spending more time finding the minimal approach than it will spend drawing.
QGraphicsView.SmartViewportUpdate	`QGraphicsView` will attempt to find an optimal update mode by analyzing the areas that require a redraw.
QGraphicsView.BoundingRectViewportUpdate	The bounding rectangle of all changes in the viewport will be redrawn. This mode has the advantage that `QGraphicsView` searches only one region for changes, minimizing time spent determining what needs redrawing. The disadvantage is that areas that have not changed also need to be redrawn.
QGraphicsView.NoViewportUpdate	`QGraphicsView` will never update its viewport when the scene changes; the user is expected to control all updates. This mode disables all (potentially slow) item visibility testing in `QGraphicsView` , and is suitable for scenes that either require a fixed frame rate, or where the viewport is otherwise updated externally.

See also

viewportUpdateMode

PySide2.QtWidgets.QGraphicsView.OptimizationFlag¶

This enum describes flags that you can enable to improve rendering performance in QGraphicsView . By default, none of these flags are set. Note that setting a flag usually imposes a side effect, and this effect can vary between paint devices and platforms.

Constant	Description
QGraphicsView.DontClipPainter	This value is obsolete and has no effect.
QGraphicsView.DontSavePainterState	When rendering, `QGraphicsView` protects the painter state (see `save()` ) when rendering the background or foreground, and when rendering each item. This allows you to leave the painter in an altered state (i.e., you can call `setPen()` or `setBrush()` without restoring the state after painting). However, if the items consistently do restore the state, you should enable this flag to prevent `QGraphicsView` from doing the same.
QGraphicsView.DontAdjustForAntialiasing	Disables `QGraphicsView` ‘s antialiasing auto-adjustment of exposed areas. Items that render antialiased lines on the boundaries of their `boundingRect()` can end up rendering parts of the line outside. To prevent rendering artifacts, `QGraphicsView` expands all exposed regions by 2 pixels in all directions. If you enable this flag, `QGraphicsView` will no longer perform these adjustments, minimizing the areas that require redrawing, which improves performance. A common side effect is that items that do draw with antialiasing can leave painting traces behind on the scene as they are moved.
QGraphicsView.IndirectPainting	Since Qt 4.6, restore the old painting algorithm that calls `drawItems()` and `drawItems()` . To be used only for compatibility with old code.

PySide2.QtWidgets.QGraphicsView.alignment()¶

Return type: Alignment

See also

setAlignment()

PySide2.QtWidgets.QGraphicsView.backgroundBrush()¶

Return type: QBrush

See also

setBackgroundBrush()

PySide2.QtWidgets.QGraphicsView.cacheMode()¶

Return type: CacheMode

See also

setCacheMode()

PySide2.QtWidgets.QGraphicsView.centerOn(pos)¶

Parameters: pos – QPointF

PySide2.QtWidgets.QGraphicsView.centerOn(x, y)

Parameters

x – qreal
y – qreal

This is an overloaded function.

This function is provided for convenience. It’s equivalent to calling centerOn ( QPointF (x , y )).

PySide2.QtWidgets.QGraphicsView.centerOn(item)

Parameters: item – QGraphicsItem

This is an overloaded function.

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

See also

ensureVisible()

PySide2.QtWidgets.QGraphicsView.dragMode()¶

Return type: DragMode

See also

setDragMode()

PySide2.QtWidgets.QGraphicsView.drawBackground(painter, rect)¶

Parameters

painter – QPainter
rect – QRectF

Draws the background of the scene using painter , before any items and the foreground are drawn. Reimplement this function to provide a custom background for this view.

If all you want is to define a color, texture or gradient for the background, you can call setBackgroundBrush() instead.

All painting is done in scene coordinates. rect is the exposed rectangle.

The default implementation fills rect using the view’s backgroundBrush . If no such brush is defined (the default), the scene’s function is called instead.

See also

drawForeground() drawBackground()

PySide2.QtWidgets.QGraphicsView.drawForeground(painter, rect)¶

Parameters

painter – QPainter
rect – QRectF

Draws the foreground of the scene using painter , after the background and all items are drawn. Reimplement this function to provide a custom foreground for this view.

If all you want is to define a color, texture or gradient for the foreground, you can call setForegroundBrush() instead.

All painting is done in scene coordinates. rect is the exposed rectangle.

The default implementation fills rect using the view’s foregroundBrush . If no such brush is defined (the default), the scene’s function is called instead.

See also

drawBackground() drawForeground()

PySide2.QtWidgets.QGraphicsView.drawItems(painter, items, options)¶

Parameters

painter – QPainter
items – QGraphicsItem[]
options – QStyleOptionGraphicsItem[]

Draws the items items in the scene using painter , after the background and before the foreground are drawn. numItems is the number of items in items and options in options . options is a list of styleoptions; one for each item. Reimplement this function to provide custom item drawing for this view.

The default implementation calls the scene’s function.

Since Qt 4.6, this function is not called anymore unless the IndirectPainting flag is given as an Optimization flag.

PySide2.QtWidgets.QGraphicsView.ensureVisible(item[, xmargin=50[, ymargin=50]])¶

Parameters

item – QGraphicsItem
xmargin – int
ymargin – int

This is an overloaded function.

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

See also

centerOn()

PySide2.QtWidgets.QGraphicsView.ensureVisible(rect[, xmargin=50[, ymargin=50]])

Parameters

rect – QRectF
xmargin – int
ymargin – int

PySide2.QtWidgets.QGraphicsView.ensureVisible(x, y, w, h[, xmargin=50[, ymargin=50]])

Parameters

x – qreal
y – qreal
w – qreal
h – qreal
xmargin – int
ymargin – int

This is an overloaded function.

This function is provided for convenience. It’s equivalent to calling ensureVisible ( QRectF (x , y , w , h ), xmargin , ymargin ).

PySide2.QtWidgets.QGraphicsView.fitInView(x, y, w, h[, aspectRadioMode=Qt.IgnoreAspectRatio])¶

Parameters

x – qreal
y – qreal
w – qreal
h – qreal
aspectRadioMode – AspectRatioMode

This is an overloaded function.

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

See also

ensureVisible() centerOn()

PySide2.QtWidgets.QGraphicsView.fitInView(rect[, aspectRadioMode=Qt.IgnoreAspectRatio])

Parameters

rect – QRectF
aspectRadioMode – AspectRatioMode

PySide2.QtWidgets.QGraphicsView.fitInView(item[, aspectRadioMode=Qt.IgnoreAspectRatio])

Parameters

item – QGraphicsItem
aspectRadioMode – AspectRatioMode

This is an overloaded function.

Ensures that item fits tightly inside the view, scaling the view according to aspectRatioMode .

See also

ensureVisible() centerOn()

PySide2.QtWidgets.QGraphicsView.foregroundBrush()¶

Return type: QBrush

See also

setForegroundBrush()

PySide2.QtWidgets.QGraphicsView.invalidateScene([rect=QRectF()[, layers=QGraphicsScene.AllLayers]])¶

Parameters

rect – QRectF
layers – SceneLayers

Invalidates and schedules a redraw of layers inside rect . rect is in scene coordinates. Any cached content for layers inside rect is unconditionally invalidated and redrawn.

You can call this function to notify QGraphicsView of changes to the background or the foreground of the scene. It is commonly used for scenes with tile-based backgrounds to notify changes when QGraphicsView has enabled background caching.

Note that QGraphicsView currently supports background caching only (see CacheBackground ). This function is equivalent to calling update() if any layer but BackgroundLayer is passed.

See also

invalidate() update()

PySide2.QtWidgets.QGraphicsView.isInteractive()¶

Return type: bool

PySide2.QtWidgets.QGraphicsView.isTransformed()¶

Return type: bool

Returns true if the view is transformed (i.e., a non-identity transform has been assigned, or the scrollbars are adjusted).

PySide2.QtWidgets.QGraphicsView.itemAt(pos)¶

Parameters: pos – QPoint
Return type: QGraphicsItem

Returns the item at position pos , which is in viewport coordinates. If there are several items at this position, this function returns the topmost item.

Example:

def mousePressEvent(self, event):
    if (item = itemAt(event.pos()):
        print "You clicked on item", item
    else:
        print "You didn't click on an item."

See also

items() Sorting

PySide2.QtWidgets.QGraphicsView.itemAt(x, y)

Parameters

x – int
y – int

Return type

QGraphicsItem

This is an overloaded function.

This function is provided for convenience. It’s equivalent to calling itemAt ( QPoint (x , y )).

PySide2.QtWidgets.QGraphicsView.items()¶

Return type

Returns a list of all the items in the associated scene, in descending stacking order (i.e., the first item in the returned list is the uppermost item).

See also

items() Sorting

PySide2.QtWidgets.QGraphicsView.items(path[, mode=Qt.IntersectsItemShape])

Parameters

path – QPainterPath
mode – ItemSelectionMode

Return type

PySide2.QtWidgets.QGraphicsView.items(pos)

Parameters: pos – QPoint
Return type

Returns a list of all the items at the position pos in the view. The items are listed in descending stacking order (i.e., the first item in the list is the uppermost item, and the last item is the lowermost item). pos is in viewport coordinates.

This function is most commonly called from within mouse event handlers in a subclass in QGraphicsView . pos is in untransformed viewport coordinates, just like pos() .

def mousePressEvent(self, event):
    print "There are", items(event->pos()).size(), "items at position", mapToScene(event->pos())

See also

items() Sorting

PySide2.QtWidgets.QGraphicsView.items(polygon[, mode=Qt.IntersectsItemShape])

Parameters

polygon – QPolygon
mode – ItemSelectionMode

Return type

PySide2.QtWidgets.QGraphicsView.items(rect[, mode=Qt.IntersectsItemShape])

Parameters

rect – QRect
mode – ItemSelectionMode

Return type

PySide2.QtWidgets.QGraphicsView.items(x, y)

Parameters

x – int
y – int

Return type

This function is provided for convenience. It’s equivalent to calling items( QPoint (x , y )).

PySide2.QtWidgets.QGraphicsView.items(x, y, w, h[, mode=Qt.IntersectsItemShape])

Parameters

x – int
y – int
w – int
h – int
mode – ItemSelectionMode

Return type

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

PySide2.QtWidgets.QGraphicsView.mapFromScene(path)¶

Parameters: path – QPainterPath
Return type: QPainterPath

PySide2.QtWidgets.QGraphicsView.mapFromScene(x, y, w, h)

Parameters

x – qreal
y – qreal
w – qreal
h – qreal

Return type

QPolygon

This function is provided for convenience. It’s equivalent to calling mapFromScene ( QRectF (x , y , w , h )).

PySide2.QtWidgets.QGraphicsView.mapFromScene(x, y)

Parameters

x – qreal
y – qreal

Return type

QPoint

This function is provided for convenience. It’s equivalent to calling mapFromScene ( QPointF (x , y )).

PySide2.QtWidgets.QGraphicsView.mapFromScene(polygon)

Parameters: polygon – QPolygonF
Return type: QPolygon

PySide2.QtWidgets.QGraphicsView.mapFromScene(point)

Parameters: point – QPointF
Return type: QPoint

PySide2.QtWidgets.QGraphicsView.mapFromScene(rect)

Parameters: rect – QRectF
Return type: QPolygon

PySide2.QtWidgets.QGraphicsView.mapToScene(x, y, w, h)¶

Parameters

x – int
y – int
w – int
h – int

Return type

QPolygonF

This function is provided for convenience. It’s equivalent to calling mapToScene ( QRect (x , y , w , h )).

PySide2.QtWidgets.QGraphicsView.mapToScene(x, y)

Parameters

x – int
y – int

Return type

QPointF

This function is provided for convenience. It’s equivalent to calling mapToScene ( QPoint (x , y )).

PySide2.QtWidgets.QGraphicsView.mapToScene(rect)

Parameters: rect – QRect
Return type: QPolygonF

PySide2.QtWidgets.QGraphicsView.mapToScene(polygon)

Parameters: polygon – QPolygon
Return type: QPolygonF

PySide2.QtWidgets.QGraphicsView.mapToScene(point)

Parameters: point – QPoint
Return type: QPointF

PySide2.QtWidgets.QGraphicsView.mapToScene(path)

Parameters: path – QPainterPath
Return type: QPainterPath

PySide2.QtWidgets.QGraphicsView.matrix()¶

Return type: QMatrix

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

PySide2.QtWidgets.QGraphicsView.optimizationFlags()¶

Return type: OptimizationFlags

See also

setOptimizationFlags()

PySide2.QtWidgets.QGraphicsView.render(painter[, target=QRectF()[, source=QRect()[, aspectRatioMode=Qt.KeepAspectRatio]]])¶

Parameters

painter – QPainter
target – QRectF
source – QRect
aspectRatioMode – AspectRatioMode

Renders the source rect, which is in view coordinates, from the scene into target , which is in paint device coordinates, using painter . This function is useful for capturing the contents of the view onto a paint device, such as a QImage (e.g., to take a screenshot), or for printing to QPrinter . For example:

scene = QGraphicsScene()
scene.addItem(...
...

view = QGraphicsView(scene)
view.show()
...

printer = QPrinter(QPrinter.HighResolution)
printer.setPageSize(QPrinter.A4)
painter = QPainter(printer)

# print, fitting the viewport contents into a full page
view.render(painter)

# print the upper half of the viewport into the lower.
# half of the page.
viewport = view.viewport()->rect()
view.render(painter,
            QRectF(0, printer.height() / 2,
                   printer.width(), printer.height() / 2),
            viewport.adjusted(0, 0, 0, -viewport.height() / 2))

If source is a null rect, this function will use viewport() -> rect() to determine what to draw. If target is a null rect, the full dimensions of painter ‘s paint device (e.g., for a QPrinter , the page size) will be used.

The source rect contents will be transformed according to aspectRatioMode to fit into the target rect. By default, the aspect ratio is kept, and source is scaled to fit in target .

See also

render()

PySide2.QtWidgets.QGraphicsView.renderHints()¶

Return type: RenderHints

See also

setRenderHints()

PySide2.QtWidgets.QGraphicsView.resetCachedContent()¶

Resets any cached content. Calling this function will clear QGraphicsView ‘s cache. If the current cache mode is CacheNone , this function does nothing.

This function is called automatically for you when the backgroundBrush or backgroundBrush properties change; you only need to call this function if you have reimplemented drawBackground() or drawBackground() to draw a custom background, and need to trigger a full redraw.

See also

cacheMode()

PySide2.QtWidgets.QGraphicsView.resetMatrix()¶: Resets the view transformation matrix to the identity matrix.

See also

resetTransform()

PySide2.QtWidgets.QGraphicsView.resetTransform()¶: Resets the view transformation to the identity matrix.

See also

transform() setTransform()

PySide2.QtWidgets.QGraphicsView.resizeAnchor()¶

Return type: ViewportAnchor

See also

setResizeAnchor()

PySide2.QtWidgets.QGraphicsView.rotate(angle)¶

Parameters: angle – qreal

Rotates the current view transformation angle degrees clockwise.

PySide2.QtWidgets.QGraphicsView.rubberBandChanged(viewportRect, fromScenePoint, toScenePoint)¶

Parameters

viewportRect – QRect
fromScenePoint – QPointF
toScenePoint – QPointF

PySide2.QtWidgets.QGraphicsView.rubberBandRect()¶

Return type: QRect

This functions returns the current rubber band area (in viewport coordinates) if the user is currently doing an itemselection with rubber band. When the user is not using the rubber band this functions returns (a null) QRectF().

Notice that part of this QRect can be outise the visual viewport. It can e.g contain negative values.

PySide2.QtWidgets.QGraphicsView.rubberBandSelectionMode()¶

Return type: ItemSelectionMode

See also

setRubberBandSelectionMode()

PySide2.QtWidgets.QGraphicsView.scale(sx, sy)¶

Parameters

sx – qreal
sy – qreal

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

PySide2.QtWidgets.QGraphicsView.scene()¶

Return type: QGraphicsScene

Returns a pointer to the scene that is currently visualized in the view. If no scene is currently visualized, 0 is returned.

See also

setScene()

PySide2.QtWidgets.QGraphicsView.sceneRect()¶

Return type: QRectF

See also

setSceneRect()

PySide2.QtWidgets.QGraphicsView.setAlignment(alignment)¶

Parameters: alignment – Alignment

See also

alignment()

PySide2.QtWidgets.QGraphicsView.setBackgroundBrush(brush)¶

Parameters: brush – QBrush

See also

backgroundBrush()

PySide2.QtWidgets.QGraphicsView.setCacheMode(mode)¶

Parameters: mode – CacheMode

See also

cacheMode()

PySide2.QtWidgets.QGraphicsView.setDragMode(mode)¶

Parameters: mode – DragMode

See also

dragMode()

PySide2.QtWidgets.QGraphicsView.setForegroundBrush(brush)¶

Parameters: brush – QBrush

See also

foregroundBrush()

PySide2.QtWidgets.QGraphicsView.setInteractive(allowed)¶

Parameters: allowed – bool

See also

isInteractive()

PySide2.QtWidgets.QGraphicsView.setMatrix(matrix[, combine=false])¶

Parameters

matrix – QMatrix
combine – bool

Sets the view’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.

The transformation matrix tranforms the scene into view coordinates. Using the default transformation, provided by the identity matrix, one pixel in the view represents one unit in the scene (e.g., a 10x10 rectangular item is drawn using 10x10 pixels in the view). If a 2x2 scaling matrix is applied, the scene will be drawn in 1:2 (e.g., a 10x10 rectangular item is then drawn using 20x20 pixels in the view).

Example:

scene = QGraphicsScene()
scene.addText("GraphicsView rotated clockwise")

view = QGraphicsView(scene)
view.rotate(90) # the text is rendered with a 90 degree clockwise rotation
view.show()

To simplify interation with items using a transformed view, QGraphicsView provides mapTo … and mapFrom … functions that can translate between scene and view coordinates. For example, you can call mapToScene() to map a view coordinate to a floating point scene coordinate, or mapFromScene() to map from floating point scene coordinates to view coordinates.

PySide2.QtWidgets.QGraphicsView.setOptimizationFlag(flag[, enabled=true])¶

Parameters

flag – OptimizationFlag
enabled – bool

Enables flag if enabled is true; otherwise disables flag .

See also

optimizationFlags

PySide2.QtWidgets.QGraphicsView.setOptimizationFlags(flags)¶

Parameters: flags – OptimizationFlags

See also

optimizationFlags()

PySide2.QtWidgets.QGraphicsView.setRenderHint(hint[, enabled=true])¶

Parameters

hint – RenderHint
enabled – bool

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

See also

renderHints

PySide2.QtWidgets.QGraphicsView.setRenderHints(hints)¶

Parameters: hints – RenderHints

See also

renderHints()

PySide2.QtWidgets.QGraphicsView.setResizeAnchor(anchor)¶

Parameters: anchor – ViewportAnchor

See also

resizeAnchor()

PySide2.QtWidgets.QGraphicsView.setRubberBandSelectionMode(mode)¶

Parameters: mode – ItemSelectionMode

See also

rubberBandSelectionMode()

PySide2.QtWidgets.QGraphicsView.setScene(scene)¶

Parameters: scene – QGraphicsScene

Sets the current scene to scene . If scene is already being viewed, this function does nothing.

When a scene is set on a view, the 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.

The view does not take ownership of scene .

See also

scene()

PySide2.QtWidgets.QGraphicsView.setSceneRect(rect)¶

Parameters: rect – QRectF

See also

sceneRect()

PySide2.QtWidgets.QGraphicsView.setSceneRect(x, y, w, h)

Parameters

x – qreal
y – qreal
w – qreal
h – qreal

PySide2.QtWidgets.QGraphicsView.setTransform(matrix[, combine=false])¶

Parameters

matrix – QTransform
combine – bool

Sets the view’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.

The transformation matrix tranforms the scene into view coordinates. Using the default transformation, provided by the identity matrix, one pixel in the view represents one unit in the scene (e.g., a 10x10 rectangular item is drawn using 10x10 pixels in the view). If a 2x2 scaling matrix is applied, the scene will be drawn in 1:2 (e.g., a 10x10 rectangular item is then drawn using 20x20 pixels in the view).

Example:

scene = QGraphicsScene()
scene.addText("GraphicsView rotated clockwise")

view = QGraphicsView(scene)
view.rotate(90) # the text is rendered with a 90 degree clockwise rotation
view.show()

To simplify interation with items using a transformed view, QGraphicsView provides mapTo … and mapFrom … functions that can translate between scene and view coordinates. For example, you can call mapToScene() to map a view coordiate to a floating point scene coordinate, or mapFromScene() to map from floating point scene coordinates to view coordinates.

PySide2.QtWidgets.QGraphicsView.setTransformationAnchor(anchor)¶

Parameters: anchor – ViewportAnchor

See also

transformationAnchor()

PySide2.QtWidgets.QGraphicsView.setViewportUpdateMode(mode)¶

Parameters: mode – ViewportUpdateMode

See also

viewportUpdateMode()

PySide2.QtWidgets.QGraphicsView.shear(sh, sv)¶

Parameters

sh – qreal
sv – qreal

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

PySide2.QtWidgets.QGraphicsView.transform()¶

Return type: QTransform

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

PySide2.QtWidgets.QGraphicsView.transformationAnchor()¶

Return type: ViewportAnchor

See also

setTransformationAnchor()

PySide2.QtWidgets.QGraphicsView.translate(dx, dy)¶

Parameters

dx – qreal
dy – qreal

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

PySide2.QtWidgets.QGraphicsView.updateScene(rects)¶

Parameters: rects –

Schedules an update of the scene rectangles rects .

See also

changed()

PySide2.QtWidgets.QGraphicsView.updateSceneRect(rect)¶

Parameters: rect – QRectF

Notifies QGraphicsView that the scene’s scene rect has changed. rect is the new scene rect. If the view already has an explicitly set scene rect, this function does nothing.

See also

sceneRect sceneRectChanged()

PySide2.QtWidgets.QGraphicsView.viewportTransform()¶