Map canvas is a class for displaying all GIS data types on a canvas. More...

#include <qgsmapcanvas.h>

Inheritance diagram for QgsMapCanvas:

Classes
class	CanvasProperties
	Deprecated to be deleted, stuff from here should be moved elsewhere. More...

Public Slots
void	layerStateChange ()
	This slot is connected to the visibility change of one or more layers. More...

void	readProject (const QDomDocument &)
	called to read map canvas settings from project More...

void	redrawAllLayers ()
	Clears all cached images and redraws all layers. More...

void	refresh ()
	Repaints the canvas map. More...

void	refreshAllLayers ()
	Reload all layers (including refreshing layer properties from their data sources), clears the cache and refreshes the canvas. More...

void	saveAsImage (const QString &fileName, QPixmap *QPixmap=nullptr, const QString &="PNG")
	Save the contents of the map canvas to disk as an image. More...

void	selectionChangedSlot ()
	Receives signal about selection change, and pass it on with layer info. More...

void	setMagnificationFactor (double factor)
	Sets the factor of magnification to apply to the map canvas. More...

void	setRenderFlag (bool flag)
	Sets whether a user has disabled canvas renders via the GUI. More...

void	setScaleLocked (bool isLocked)
	Lock the scale, so zooming can be performed using magnication. More...

void	stopRendering ()
	stop rendering (if there is any right now) More...

void	writeProject (QDomDocument &)
	called to write map canvas settings to project More...

void	zoomIn ()
	Zoom in with fixed factor. More...

void	zoomOut ()
	Zoom out with fixed factor. More...

void	zoomToSelected (QgsVectorLayer *layer=nullptr)
	Zoom to the extent of the selected features of provided (vector) layer. More...

Signals
void	canvasColorChanged ()
	Emitted when canvas background color changes. More...

void	currentLayerChanged (QgsMapLayer *layer)
	Emitted when the current layer is changed. More...

void	destinationCrsChanged ()
	Emitted when map CRS has changed. More...

void	extentsChanged ()
	Emitted when the extents of the map change. More...

void	keyPressed (QKeyEvent *e)
	Emit key press event. More...

void	keyReleased (QKeyEvent *e)
	Emit key release event. More...

void	layersChanged ()
	Emitted when a new set of layers has been received. More...

void	layerStyleOverridesChanged ()
	Emitted when the configuration of overridden layer styles changes. More...

void	magnificationChanged (double)
	Emitted when the scale of the map changes. More...

void	mapCanvasRefreshed ()
	Emitted when canvas finished a refresh request. More...

void	mapToolSet (QgsMapTool newTool, QgsMapTool oldTool)
	Emit map tool changed with the old tool. More...

void	messageEmitted (const QString &title, const QString &message, Qgis::MessageLevel=Qgis::Info)
	emit a message (usually to be displayed in a message bar) More...

void	renderComplete (QPainter *)
	Emitted when the canvas has rendered. More...

void	renderErrorOccurred (const QString &error, QgsMapLayer *layer)
	Emitted whenever an error is encountered during a map render operation. More...

void	renderStarting ()
	Emitted when the canvas is about to be rendered. More...

void	rotationChanged (double)
	Emitted when the rotation of the map changes. More...

void	scaleChanged (double)
	Emitted when the scale of the map changes. More...

void	selectionChanged (QgsVectorLayer *layer)
	Emitted when selection in any layer gets changed. More...

void	themeChanged (const QString &theme)
	Emitted when the canvas has been assigned a different map theme. More...

void	transformContextChanged ()
	Emitted when the canvas transform context is changed. More...

void	xyCoordinates (const QgsPointXY &p)
	Emits current mouse position. More...

void	zoomLastStatusChanged (bool)
	Emitted when zoom last status changed. More...

void	zoomNextStatusChanged (bool)
	Emitted when zoom next status changed. More...

Public Member Functions
	QgsMapCanvas (QWidget *parent=nullptr)
	Constructor. More...

	~QgsMapCanvas () override

QList< QgsMapCanvasAnnotationItem * >	annotationItems () const
	Returns a list of all annotation items in the canvas. More...

bool	annotationsVisible () const
	Returns `true` if annotations are visible within the map canvas. More...

bool	antiAliasingEnabled () const
	`true` if antialising is enabled More...

QColor	canvasColor () const
	Read property of QColor bgColor. More...

QgsPointXY	center () const
	Gets map center, in geographical coordinates. More...

void	clearCache ()
	Make sure to remove any rendered images from cache (does nothing if cache is not enabled) More...

void	clearExtentHistory ()

QgsMapLayer *	currentLayer ()
	returns current layer (set by legend widget) More...

QgsExpressionContextScope *	defaultExpressionContextScope ()
	Creates a new scope which contains default variables and functions relating to the map canvas. More...

void	enableAntiAliasing (bool flag)
	used to determine if anti-aliasing is enabled or not More...

void	enableMapTileRendering (bool flag)
	sets map tile rendering flag More...

QgsExpressionContextScope &	expressionContextScope ()
	Returns a reference to the expression context scope for the map canvas. More...

const QgsExpressionContextScope &	expressionContextScope () const
	Returns a const reference to the expression context scope for the map canvas. More...

QgsRectangle	extent () const
	Returns the current zoom extent of the map canvas. More...

void	flashFeatureIds (QgsVectorLayer *layer, const QgsFeatureIds &ids, const QColor &startColor=QColor(255, 0, 0, 255), const QColor &endColor=QColor(255, 0, 0, 0), int flashes=3, int duration=500)
	Causes a set of features with matching ids from a vector layer to flash within the canvas. More...

void	flashGeometries (const QList< QgsGeometry > &geometries, const QgsCoordinateReferenceSystem &crs=QgsCoordinateReferenceSystem(), const QColor &startColor=QColor(255, 0, 0, 255), const QColor &endColor=QColor(255, 0, 0, 0), int flashes=3, int duration=500)
	Causes a set of geometries to flash within the canvas. More...

void	freeze (bool frozen=true)
	Freeze/thaw the map canvas. More...

QgsRectangle	fullExtent () const
	Returns the combined extent for all layers on the map canvas. More...

const QgsMapToPixel *	getCoordinateTransform ()
	Gets the current coordinate transform. More...

bool	isCachingEnabled () const
	Check whether images of rendered layers are curerently being cached. More...

bool	isDrawing ()
	Find out whether rendering is in progress. More...

bool	isFrozen () const
	Returns `true` if canvas is frozen. More...

bool	isParallelRenderingEnabled () const
	Check whether the layers are rendered in parallel or sequentially. More...

const QgsLabelingEngineSettings &	labelingEngineSettings () const
	Returns global labeling engine settings from the internal map settings. More...

const QgsLabelingResults *	labelingResults () const
	Gets access to the labeling results (may be `nullptr`) More...

QgsMapLayer *	layer (int index)
	Returns the map layer at position index in the layer stack. More...

int	layerCount () const
	Returns number of layers on the map. More...

QList< QgsMapLayer * >	layers () const
	Returns the list of layers shown within the map canvas. More...

QMap< QString, QString >	layerStyleOverrides () const
	Returns the stored overrides of styles for layers. More...

double	magnificationFactor () const
	Returns the magnification factor. More...

const QgsMapSettings &	mapSettings () const
	Gets access to properties used for map rendering. More...

QgsMapTool *	mapTool ()
	Returns the currently active tool. More...

QgsUnitTypes::DistanceUnit	mapUnits () const
	Convenience function for returning the current canvas map units. More...

double	mapUnitsPerPixel () const
	Returns the mapUnitsPerPixel (map units per pixel) for the canvas. More...

int	mapUpdateInterval () const
	Find out how often map preview should be updated while it is being rendered (in milliseconds) More...

QPoint	mouseLastXY ()
	returns last position of mouse cursor More...

void	panAction (QMouseEvent *event)
	Called when mouse is moving and pan is activated. More...

void	panActionEnd (QPoint releasePoint)
	Ends pan action and redraws the canvas. More...

void	panToFeatureIds (QgsVectorLayer *layer, const QgsFeatureIds &ids, bool alwaysRecenter=true)
	Centers canvas extent to feature ids. More...

void	panToSelected (QgsVectorLayer *layer=nullptr)
	Pan to the selected features of current (vector) layer keeping same extent. More...

bool	previewJobsEnabled () const
	Returns `true` if canvas map preview jobs (low priority render jobs which render portions of the view just outside of the canvas extent, to allow preview of these out-of-canvas areas when panning or zooming out the map) are enabled for the canvas. More...

QgsPreviewEffect::PreviewMode	previewMode () const
	Returns the current preview mode for the map canvas. More...

bool	previewModeEnabled () const
	Returns whether a preview mode is enabled for the map canvas. More...

bool	renderFlag () const
	Returns `true` if canvas render is disabled as a result of user disabling renders via the GUI. More...

double	rotation () const
	Gets the current map canvas rotation in clockwise degrees. More...

double	scale () const
	Returns the last reported scale of the canvas. More...

bool	scaleLocked () const
	Returns whether the scale is locked, so zooming can be performed using magnication. More...

QColor	selectionColor () const
	Returns color for selected features. More...

void	setAnnotationsVisible (bool visible)
	Sets whether annotations are visible in the canvas. More...

void	setCachingEnabled (bool enabled)
	Set whether to cache images of rendered layers. More...

void	setCanvasColor (const QColor &_newVal)
	Write property of QColor bgColor. More...

void	setCenter (const QgsPointXY &center)
	Set the center of the map canvas, in geographical coordinates. More...

void	setCurrentLayer (QgsMapLayer *layer)

void	setCustomDropHandlers (const QVector< QPointer< QgsCustomDropHandler >> &handlers)
	Sets a list of custom drop handlers to use when drop events occur on the canvas. More...

void	setDestinationCrs (const QgsCoordinateReferenceSystem &crs)
	sets destination coordinate reference system More...

void	setExpressionContextScope (const QgsExpressionContextScope &scope)
	Sets an expression context scope for the map canvas. More...

void	setExtent (const QgsRectangle &r, bool magnified=false)
	Sets the extent of the map canvas. More...

void	setLabelingEngineSettings (const QgsLabelingEngineSettings &settings)
	Sets global labeling engine settings in the internal map settings. More...

void	setLayers (const QList< QgsMapLayer *> &layers)
	Sets the list of layers that should be shown in the canvas. More...

void	setLayerStyleOverrides (const QMap< QString, QString > &overrides)
	Sets the stored overrides of styles for rendering layers. More...

void	setMapSettingsFlags (QgsMapSettings::Flags flags)
	Resets the flags for the canvas' map settings. More...

void	setMapTool (QgsMapTool *mapTool, bool clean=false)
	Sets the map tool currently being used on the canvas. More...

void	setMapUpdateInterval (int timeMilliseconds)
	Set how often map preview should be updated while it is being rendered (in milliseconds) More...

void	setParallelRenderingEnabled (bool enabled)
	Set whether the layers are rendered in parallel or sequentially. More...

void	setPreviewJobsEnabled (bool enabled)
	Sets whether canvas map preview jobs (low priority render jobs which render portions of the view just outside of the canvas extent, to allow preview of these out-of-canvas areas when panning or zooming out the map) are enabled for the canvas. More...

void	setPreviewMode (QgsPreviewEffect::PreviewMode mode)
	Sets a preview mode for the map canvas. More...

void	setPreviewModeEnabled (bool previewEnabled)
	Enables a preview mode for the map canvas. More...

bool	setReferencedExtent (const QgsReferencedRectangle &extent) SIP_THROW(QgsCsException)
	Sets the canvas to the specified extent. More...

void	setRotation (double degrees)
	Set the rotation of the map canvas in clockwise degrees. More...

void	setSegmentationTolerance (double tolerance)
	Sets the segmentation tolerance applied when rendering curved geometries. More...

void	setSegmentationToleranceType (QgsAbstractGeometry::SegmentationToleranceType type)
	Sets segmentation tolerance type (maximum angle or maximum difference between curve and approximation) More...

void	setSelectionColor (const QColor &color)
	Set color of selected vector features. More...

void	setSnappingUtils (QgsSnappingUtils *utils)
	Assign an instance of snapping utils to the map canvas. More...

void	setTheme (const QString &theme)
	Sets a map theme to show in the canvas. More...

void	setWheelFactor (double factor)
	Sets wheel zoom factor (should be greater than 1) More...

QgsSnappingUtils *	snappingUtils () const
	Returns snapping utility class that is associated with map canvas. More...

QString	theme () const
	Returns the map's theme shown in the canvas, if set. More...

void	unsetMapTool (QgsMapTool *mapTool)
	Unset the current map tool or last non zoom tool. More...

void	updateScale ()
	Emits signal scaleChanged to update scale in main window. More...

void	waitWhileRendering ()
	Blocks until the rendering job has finished. More...

void	zoomByFactor (double scaleFactor, const QgsPointXY *center=nullptr)
	Zoom with the factor supplied. More...

void	zoomScale (double scale)
	Zooms the canvas to a specific scale. More...

void	zoomToFeatureExtent (QgsRectangle &rect)
	Zooms to feature extent. More...

void	zoomToFeatureIds (QgsVectorLayer *layer, const QgsFeatureIds &ids)
	Set canvas extent to the bounding box of a set of features. More...

void	zoomToFullExtent ()
	Zoom to the full extent of all layers. More...

void	zoomToNextExtent ()
	Zoom to the next extent (view) More...

void	zoomToPreviousExtent ()
	Zoom to the previous extent (view) More...

void	zoomWithCenter (int x, int y, bool zoomIn)
	Zooms in/out with a given center. More...

Protected Slots
void	updateCanvasItemPositions ()
	called on resize or changed extent to notify canvas items to change their rectangle More...

Protected Member Functions
void	dragEnterEvent (QDragEnterEvent *e) override

void	dropEvent (QDropEvent *event) override

bool	event (QEvent *e) override

void	keyPressEvent (QKeyEvent *e) override

void	keyReleaseEvent (QKeyEvent *e) override

void	mouseDoubleClickEvent (QMouseEvent *e) override

void	mouseMoveEvent (QMouseEvent *e) override

void	mousePressEvent (QMouseEvent *e) override

void	mouseReleaseEvent (QMouseEvent *e) override

void	moveCanvasContents (bool reset=false)
	called when panning is in action, reset indicates end of panning More...

void	paintEvent (QPaintEvent *e) override

void	resizeEvent (QResizeEvent *e) override

void	wheelEvent (QWheelEvent *e) override

Protected Attributes
std::unique_ptr< CanvasProperties >	mCanvasProperties
	Handle pattern for implementation object. More...

Properties
bool	previewJobsEnabled

QString	theme

Friends
class	TestQgsMapCanvas

Detailed Description

Map canvas is a class for displaying all GIS data types on a canvas.

Definition at line 75 of file qgsmapcanvas.h.

Constructor & Destructor Documentation

◆ QgsMapCanvas()

QgsMapCanvas::QgsMapCanvas ( QWidget * parent = nullptr )

Constructor.

Definition at line 108 of file qgsmapcanvas.cpp.

◆ ~QgsMapCanvas()

QgsMapCanvas::~QgsMapCanvas ( )

override

Definition at line 219 of file qgsmapcanvas.cpp.

Member Function Documentation

◆ annotationItems()

QList< QgsMapCanvasAnnotationItem * > QgsMapCanvas::annotationItems ( ) const

Returns a list of all annotation items in the canvas.

Since: QGIS 3.0

Definition at line 2360 of file qgsmapcanvas.cpp.

◆ annotationsVisible()

bool QgsMapCanvas::annotationsVisible ( ) const

inline

Returns true if annotations are visible within the map canvas.

See also: setAnnotationsVisible()

Since: QGIS 3.0

Definition at line 613 of file qgsmapcanvas.h.

◆ antiAliasingEnabled()

bool QgsMapCanvas::antiAliasingEnabled ( ) const

inline

true if antialising is enabled

Definition at line 483 of file qgsmapcanvas.h.

◆ canvasColor()

QColor QgsMapCanvas::canvasColor ( ) const

Read property of QColor bgColor.

Definition at line 1815 of file qgsmapcanvas.cpp.

◆ canvasColorChanged

void QgsMapCanvas::canvasColorChanged ( )

signal

Emitted when canvas background color changes.

Since: QGIS 3.0

◆ center()

QgsPointXY QgsMapCanvas::center ( ) const

Gets map center, in geographical coordinates.

Since: QGIS 2.8

Definition at line 915 of file qgsmapcanvas.cpp.

◆ clearCache()

void QgsMapCanvas::clearCache ( )

Make sure to remove any rendered images from cache (does nothing if cache is not enabled)

Since: QGIS 2.4

Definition at line 453 of file qgsmapcanvas.cpp.

◆ clearExtentHistory()

void QgsMapCanvas::clearExtentHistory ( )

Definition at line 996 of file qgsmapcanvas.cpp.

◆ currentLayer()

QgsMapLayer * QgsMapCanvas::currentLayer ( )

returns current layer (set by legend widget)

Definition at line 480 of file qgsmapcanvas.cpp.

◆ currentLayerChanged

void QgsMapCanvas::currentLayerChanged ( QgsMapLayer * layer )

signal

Emitted when the current layer is changed.

Since: QGIS 2.8

◆ defaultExpressionContextScope()

QgsExpressionContextScope * QgsMapCanvas::defaultExpressionContextScope ( )

Creates a new scope which contains default variables and functions relating to the map canvas.

See also: expressionContextScope(); setExpressionContextScope()

Since: QGIS 3.4

Definition at line 485 of file qgsmapcanvas.cpp.

◆ destinationCrsChanged

void QgsMapCanvas::destinationCrsChanged ( )

signal

Emitted when map CRS has changed.

Since: QGIS 2.4

◆ dragEnterEvent()

void QgsMapCanvas::dragEnterEvent ( QDragEnterEvent * e )

overrideprotected

Definition at line 2259 of file qgsmapcanvas.cpp.

◆ dropEvent()

void QgsMapCanvas::dropEvent ( QDropEvent * event )

overrideprotected

Definition at line 2043 of file qgsmapcanvas.cpp.

◆ enableAntiAliasing()

void QgsMapCanvas::enableAntiAliasing ( bool flag )

used to determine if anti-aliasing is enabled or not

Definition at line 278 of file qgsmapcanvas.cpp.

◆ enableMapTileRendering()

void QgsMapCanvas::enableMapTileRendering ( bool flag )

sets map tile rendering flag

Definition at line 283 of file qgsmapcanvas.cpp.

◆ event()

bool QgsMapCanvas::event ( QEvent * e )

overrideprotected

Definition at line 2303 of file qgsmapcanvas.cpp.

◆ expressionContextScope() [1/2]

QgsExpressionContextScope& QgsMapCanvas::expressionContextScope ( )

inline

Returns a reference to the expression context scope for the map canvas.

This scope is injected into the expression context used for rendering the map, and can be used to apply specific variable overrides for expression evaluation for the map canvas render.

See also: setExpressionContextScope(); defaultExpressionContextScope()

Since: QGIS 2.12

Definition at line 573 of file qgsmapcanvas.h.

◆ expressionContextScope() [2/2]

const QgsExpressionContextScope& QgsMapCanvas::expressionContextScope ( ) const

inline

Returns a const reference to the expression context scope for the map canvas.

See also: setExpressionContextScope(); defaultExpressionContextScope()

Note: not available in Python bindings

Since: QGIS 2.12

Definition at line 582 of file qgsmapcanvas.h.

◆ extent()

QgsRectangle QgsMapCanvas::extent ( ) const

Returns the current zoom extent of the map canvas.

Definition at line 821 of file qgsmapcanvas.cpp.

◆ extentsChanged

void QgsMapCanvas::extentsChanged ( )

signal

Emitted when the extents of the map change.

◆ flashFeatureIds()

void QgsMapCanvas::flashFeatureIds	(	QgsVectorLayer *	layer,
		const QgsFeatureIds &	ids,
		const QColor &	startColor = `QColor( 255, 0, 0, 255 )`,
		const QColor &	endColor = `QColor( 255, 0, 0, 0 )`,
		int	flashes = `3`,
		int	duration = `500`
	)

Causes a set of features with matching ids from a vector layer to flash within the canvas.

The startColor and endColor can be specified, along with the number of flashes and duration of each flash (in milliseconds).

Note: If the features or geometries are already available, flashGeometries() is much more efficient.

See also: flashGeometries()

Since: QGIS 3.0

Definition at line 1185 of file qgsmapcanvas.cpp.

◆ flashGeometries()

void QgsMapCanvas::flashGeometries	(	const QList< QgsGeometry > &	geometries,
		const QgsCoordinateReferenceSystem &	crs = `QgsCoordinateReferenceSystem()`,
		const QColor &	startColor = `QColor( 255, 0, 0, 255 )`,
		const QColor &	endColor = `QColor( 255, 0, 0, 0 )`,
		int	flashes = `3`,
		int	duration = `500`
	)

Causes a set of geometries to flash within the canvas.

If crs is a valid coordinate reference system, the geometries will be automatically transformed from this CRS to the canvas CRS.

The startColor and endColor can be specified, along with the number of flashes and duration of each flash (in milliseconds).

See also: flashFeatureIds()

Since: QGIS 3.0

Definition at line 1208 of file qgsmapcanvas.cpp.

◆ freeze()

void QgsMapCanvas::freeze ( bool frozen = true )

Freeze/thaw the map canvas.

This is used to prevent the canvas from responding to events while layers are being added/removed etc.

Parameters

frozen Boolean specifying if the canvas should be frozen (true) or thawed (false). Default is true.

See also: isFrozen(); setRenderFlag(). freeze() should be used to programmatically halt map updates, while setRenderFlag() should only be used when users disable rendering via GUI.

Definition at line 1871 of file qgsmapcanvas.cpp.

◆ fullExtent()

QgsRectangle QgsMapCanvas::fullExtent ( ) const

Returns the combined extent for all layers on the map canvas.

Definition at line 826 of file qgsmapcanvas.cpp.

◆ getCoordinateTransform()

const QgsMapToPixel * QgsMapCanvas::getCoordinateTransform ( )

Gets the current coordinate transform.

Definition at line 318 of file qgsmapcanvas.cpp.

◆ isCachingEnabled()

bool QgsMapCanvas::isCachingEnabled ( ) const

Check whether images of rendered layers are curerently being cached.

Since: QGIS 2.4

Definition at line 448 of file qgsmapcanvas.cpp.

◆ isDrawing()

bool QgsMapCanvas::isDrawing ( )

Find out whether rendering is in progress.

Definition at line 311 of file qgsmapcanvas.cpp.

◆ isFrozen()

bool QgsMapCanvas::isFrozen ( ) const

Returns true if canvas is frozen.

See also: renderFlag(). isFrozen() should be used to determine whether map updates have been halted programmatically, while renderFlag() should be used to determine whether a user has disabled rendering via GUI.; freeze()

Definition at line 1876 of file qgsmapcanvas.cpp.

◆ isParallelRenderingEnabled()

bool QgsMapCanvas::isParallelRenderingEnabled ( ) const

Check whether the layers are rendered in parallel or sequentially.

Since: QGIS 2.4

Definition at line 464 of file qgsmapcanvas.cpp.

◆ keyPressed

void QgsMapCanvas::keyPressed ( QKeyEvent * e )

signal

Emit key press event.

◆ keyPressEvent()

void QgsMapCanvas::keyPressEvent ( QKeyEvent * e )

overrideprotected

Definition at line 1285 of file qgsmapcanvas.cpp.

◆ keyReleased

void QgsMapCanvas::keyReleased ( QKeyEvent * e )

signal

Emit key release event.

◆ keyReleaseEvent()

void QgsMapCanvas::keyReleaseEvent ( QKeyEvent * e )

overrideprotected

Definition at line 1379 of file qgsmapcanvas.cpp.

◆ labelingEngineSettings()

const QgsLabelingEngineSettings & QgsMapCanvas::labelingEngineSettings ( ) const

Returns global labeling engine settings from the internal map settings.

Since: QGIS 3.0

Definition at line 2391 of file qgsmapcanvas.cpp.

◆ labelingResults()

const QgsLabelingResults * QgsMapCanvas::labelingResults ( ) const

Gets access to the labeling results (may be nullptr)

Since: QGIS 2.4

Definition at line 421 of file qgsmapcanvas.cpp.

◆ layer()

QgsMapLayer * QgsMapCanvas::layer ( int index )

Returns the map layer at position index in the layer stack.

Definition at line 288 of file qgsmapcanvas.cpp.

◆ layerCount()

int QgsMapCanvas::layerCount ( ) const

Returns number of layers on the map.

Definition at line 1854 of file qgsmapcanvas.cpp.

◆ layers()

QList< QgsMapLayer * > QgsMapCanvas::layers ( ) const

Returns the list of layers shown within the map canvas.

See also: setLayers()

Definition at line 1860 of file qgsmapcanvas.cpp.

◆ layersChanged

void QgsMapCanvas::layersChanged ( )

signal

Emitted when a new set of layers has been received.

◆ layerStateChange

void QgsMapCanvas::layerStateChange ( )

slot

This slot is connected to the visibility change of one or more layers.

Definition at line 1865 of file qgsmapcanvas.cpp.

◆ layerStyleOverrides()

QMap< QString, QString > QgsMapCanvas::layerStyleOverrides ( ) const

Returns the stored overrides of styles for layers.

See also: setLayerStyleOverrides().

Since: QGIS 2.12

Definition at line 1891 of file qgsmapcanvas.cpp.

◆ layerStyleOverridesChanged

void QgsMapCanvas::layerStyleOverridesChanged ( )

signal

Emitted when the configuration of overridden layer styles changes.

Since: QGIS 2.12

◆ magnificationChanged

void QgsMapCanvas::magnificationChanged ( double )

signal

Emitted when the scale of the map changes.

Since: QGIS 2.16

◆ magnificationFactor()

double QgsMapCanvas::magnificationFactor ( ) const

Returns the magnification factor.

Since: QGIS 2.16

Definition at line 273 of file qgsmapcanvas.cpp.

◆ mapCanvasRefreshed

void QgsMapCanvas::mapCanvasRefreshed ( )

signal

Emitted when canvas finished a refresh request.

◆ mapSettings()

const QgsMapSettings & QgsMapCanvas::mapSettings ( ) const

Gets access to properties used for map rendering.

Since: QGIS 2.4

Definition at line 374 of file qgsmapcanvas.cpp.

◆ mapTool()

QgsMapTool * QgsMapCanvas::mapTool ( )

Returns the currently active tool.

Definition at line 2002 of file qgsmapcanvas.cpp.

◆ mapToolSet

void QgsMapCanvas::mapToolSet	(	QgsMapTool *	newTool,
		QgsMapTool *	oldTool
	)

signal

Emit map tool changed with the old tool.

Since: QGIS 2.3

◆ mapUnits()

QgsUnitTypes::DistanceUnit QgsMapCanvas::mapUnits ( ) const

Convenience function for returning the current canvas map units.

The map units are dictated by the canvas' destinationCrs() map units.

Definition at line 1886 of file qgsmapcanvas.cpp.

◆ mapUnitsPerPixel()

double QgsMapCanvas::mapUnitsPerPixel ( ) const

Returns the mapUnitsPerPixel (map units per pixel) for the canvas.

Definition at line 1881 of file qgsmapcanvas.cpp.

◆ mapUpdateInterval()

int QgsMapCanvas::mapUpdateInterval ( ) const

Find out how often map preview should be updated while it is being rendered (in milliseconds)

Since: QGIS 2.4

Definition at line 474 of file qgsmapcanvas.cpp.

◆ messageEmitted

void QgsMapCanvas::messageEmitted	(	const QString &	title,
		const QString &	message,
		Qgis::MessageLevel	= `Qgis::Info`
	)

signal

emit a message (usually to be displayed in a message bar)

◆ mouseDoubleClickEvent()

void QgsMapCanvas::mouseDoubleClickEvent ( QMouseEvent * e )

overrideprotected

Definition at line 1411 of file qgsmapcanvas.cpp.

◆ mouseLastXY()

QPoint QgsMapCanvas::mouseLastXY ( )

returns last position of mouse cursor

Definition at line 2077 of file qgsmapcanvas.cpp.

◆ mouseMoveEvent()

void QgsMapCanvas::mouseMoveEvent ( QMouseEvent * e )

overrideprotected

Definition at line 1705 of file qgsmapcanvas.cpp.

◆ mousePressEvent()

void QgsMapCanvas::mousePressEvent ( QMouseEvent * e )

overrideprotected

Definition at line 1466 of file qgsmapcanvas.cpp.

◆ mouseReleaseEvent()

void QgsMapCanvas::mouseReleaseEvent ( QMouseEvent * e )

overrideprotected

Definition at line 1504 of file qgsmapcanvas.cpp.

◆ moveCanvasContents()

void QgsMapCanvas::moveCanvasContents ( bool reset = false )

protected

called when panning is in action, reset indicates end of panning

Definition at line 2034 of file qgsmapcanvas.cpp.

◆ paintEvent()

void QgsMapCanvas::paintEvent ( QPaintEvent * e )

overrideprotected

Definition at line 1594 of file qgsmapcanvas.cpp.

◆ panAction()

void QgsMapCanvas::panAction ( QMouseEvent * event )

Called when mouse is moving and pan is activated.

Definition at line 2026 of file qgsmapcanvas.cpp.

◆ panActionEnd()

void QgsMapCanvas::panActionEnd ( QPoint releasePoint )

Ends pan action and redraws the canvas.

Definition at line 2007 of file qgsmapcanvas.cpp.

◆ panToFeatureIds()

void QgsMapCanvas::panToFeatureIds	(	QgsVectorLayer *	layer,
		const QgsFeatureIds &	ids,
		bool	alwaysRecenter = `true`
	)

Centers canvas extent to feature ids.

Parameters

layer	the vector layer
ids	the feature ids
alwaysRecenter	if false, the canvas is recentered only if the bounding box is not contained within the current extent

Definition at line 1104 of file qgsmapcanvas.cpp.

◆ panToSelected()

void QgsMapCanvas::panToSelected ( QgsVectorLayer * layer = nullptr )

Pan to the selected features of current (vector) layer keeping same extent.

Definition at line 1162 of file qgsmapcanvas.cpp.

◆ previewJobsEnabled()

bool QgsMapCanvas::previewJobsEnabled ( ) const

Returns true if canvas map preview jobs (low priority render jobs which render portions of the view just outside of the canvas extent, to allow preview of these out-of-canvas areas when panning or zooming out the map) are enabled for the canvas.

See also: setPreviewJobsEnabled()

Since: QGIS 3.0

◆ previewMode()

QgsPreviewEffect::PreviewMode QgsMapCanvas::previewMode ( ) const

Returns the current preview mode for the map canvas.

This setting only has an effect if previewModeEnabled is true.

Returns: preview mode for map canvas

See also: setPreviewMode; previewModeEnabled

Since: QGIS 2.3

Definition at line 2112 of file qgsmapcanvas.cpp.

◆ previewModeEnabled()

bool QgsMapCanvas::previewModeEnabled ( ) const

Returns whether a preview mode is enabled for the map canvas.

Returns: true if a preview mode is currently enabled

See also: setPreviewModeEnabled; previewMode

Since: QGIS 2.3

Definition at line 2092 of file qgsmapcanvas.cpp.

◆ readProject

void QgsMapCanvas::readProject ( const QDomDocument & doc )

slot

called to read map canvas settings from project

Definition at line 2138 of file qgsmapcanvas.cpp.

◆ redrawAllLayers

void QgsMapCanvas::redrawAllLayers ( )

slot

Clears all cached images and redraws all layers.

Note: Unlike refreshAllLayers(), this does NOT reload layers themselves, and accordingly is more "lightweight". Use this method when only an update of the layer's renderers is required.

Since: QGIS 3.10

Definition at line 2333 of file qgsmapcanvas.cpp.

◆ refresh

void QgsMapCanvas::refresh ( )

slot

Repaints the canvas map.

Definition at line 493 of file qgsmapcanvas.cpp.

◆ refreshAllLayers

void QgsMapCanvas::refreshAllLayers ( )

slot

Reload all layers (including refreshing layer properties from their data sources), clears the cache and refreshes the canvas.

Note: Consider using the less expensive redrawAllLayers() method if a layer reload from the data provider is not required.

Since: QGIS 2.9

Definition at line 2321 of file qgsmapcanvas.cpp.

◆ renderComplete

void QgsMapCanvas::renderComplete ( QPainter * )

signal

Emitted when the canvas has rendered.

Passes a pointer to the painter on which the map was drawn. This is useful for plugins that wish to draw on the map after it has been rendered. Passing the painter allows plugins to work when the map is being rendered onto a pixmap other than the mapCanvas own pixmap member. TODO: deprecate when decorations are reimplemented as map canvas items

anything related to rendering progress is not visible outside of map canvas
additional drawing shall be done directly within the renderer job or independently as a map canvas item

◆ renderErrorOccurred

void QgsMapCanvas::renderErrorOccurred	(	const QString &	error,
		QgsMapLayer *	layer
	)

signal

Emitted whenever an error is encountered during a map render operation.

The layer argument indicates the associated map layer, if available.

Since: QGIS 3.10.0

◆ renderFlag()

bool QgsMapCanvas::renderFlag ( ) const

inline

Returns true if canvas render is disabled as a result of user disabling renders via the GUI.

See also: setRenderFlag(); isFrozen(). isFrozen() should be used to determine whether map updates have been halted programmatically, while renderFlag() should be used to determine whether a user has disabled rendering via GUI.

Definition at line 384 of file qgsmapcanvas.h.

◆ renderStarting

void QgsMapCanvas::renderStarting ( )

signal

Emitted when the canvas is about to be rendered.

◆ resizeEvent()

void QgsMapCanvas::resizeEvent ( QResizeEvent * e )

overrideprotected

Definition at line 1565 of file qgsmapcanvas.cpp.

◆ rotation()

double QgsMapCanvas::rotation ( ) const

Gets the current map canvas rotation in clockwise degrees.

Since: QGIS 2.8

Definition at line 926 of file qgsmapcanvas.cpp.

◆ rotationChanged

void QgsMapCanvas::rotationChanged ( double )

signal

Emitted when the rotation of the map changes.

Since: QGIS 2.8

◆ saveAsImage

void QgsMapCanvas::saveAsImage	(	const QString &	fileName,
		QPixmap *	QPixmap = `nullptr`,
		const QString &	format = `"PNG"`
	)

slot

Save the contents of the map canvas to disk as an image.

Definition at line 751 of file qgsmapcanvas.cpp.

◆ scale()

double QgsMapCanvas::scale ( ) const

Returns the last reported scale of the canvas.

The scale value indicates the scale denominator, e.g. 1000.0 for a 1:1000 map.

Definition at line 306 of file qgsmapcanvas.cpp.

◆ scaleChanged

void QgsMapCanvas::scaleChanged ( double )

signal

Emitted when the scale of the map changes.

◆ scaleLocked()

bool QgsMapCanvas::scaleLocked ( ) const

inline

Returns whether the scale is locked, so zooming can be performed using magnication.

See also: setScaleLocked()

Since: QGIS 2.16

Definition at line 477 of file qgsmapcanvas.h.

◆ selectionChanged

void QgsMapCanvas::selectionChanged ( QgsVectorLayer * layer )

signal

Emitted when selection in any layer gets changed.

◆ selectionChangedSlot

void QgsMapCanvas::selectionChangedSlot ( )

slot

Receives signal about selection change, and pass it on with layer info.

Definition at line 2248 of file qgsmapcanvas.cpp.

◆ selectionColor()

QColor QgsMapCanvas::selectionColor ( ) const

Returns color for selected features.

Since: QGIS 3.0

Definition at line 1849 of file qgsmapcanvas.cpp.

◆ setAnnotationsVisible()

void QgsMapCanvas::setAnnotationsVisible ( bool visible )

Sets whether annotations are visible in the canvas.

See also: annotationsVisible()

Since: QGIS 3.0

Definition at line 2376 of file qgsmapcanvas.cpp.

◆ setCachingEnabled()

void QgsMapCanvas::setCachingEnabled ( bool enabled )

Set whether to cache images of rendered layers.

Since: QGIS 2.4

Definition at line 426 of file qgsmapcanvas.cpp.

◆ setCanvasColor()

void QgsMapCanvas::setCanvasColor ( const QColor & _newVal )

Write property of QColor bgColor.

Definition at line 1790 of file qgsmapcanvas.cpp.

◆ setCenter()

void QgsMapCanvas::setCenter ( const QgsPointXY & center )

Set the center of the map canvas, in geographical coordinates.

Since: QGIS 2.8

Definition at line 901 of file qgsmapcanvas.cpp.

◆ setCurrentLayer()

void QgsMapCanvas::setCurrentLayer ( QgsMapLayer * layer )

Definition at line 297 of file qgsmapcanvas.cpp.

◆ setCustomDropHandlers()

void QgsMapCanvas::setCustomDropHandlers ( const QVector< QPointer< QgsCustomDropHandler >> & handlers )

Sets a list of custom drop handlers to use when drop events occur on the canvas.

Note: Not available in Python bindings

Since: QGIS 3.10

Definition at line 722 of file qgsmapcanvas.cpp.

◆ setDestinationCrs()

void QgsMapCanvas::setDestinationCrs ( const QgsCoordinateReferenceSystem & crs )

sets destination coordinate reference system

Since: QGIS 2.4

Definition at line 379 of file qgsmapcanvas.cpp.

◆ setExpressionContextScope()

void QgsMapCanvas::setExpressionContextScope ( const QgsExpressionContextScope & scope )

inline

Sets an expression context scope for the map canvas.

This scope is injected into the expression context used for rendering the map, and can be used to apply specific variable overrides for expression evaluation for the map canvas render. This method will overwrite the existing expression context scope for the canvas.

Parameters

scope new expression context scope

See also: expressionContextScope(); defaultExpressionContextScope()

Since: QGIS 2.12

Definition at line 563 of file qgsmapcanvas.h.

◆ setExtent()

void QgsMapCanvas::setExtent	(	const QgsRectangle &	r,
		bool	magnified = `false`
	)

Sets the extent of the map canvas.

Definition at line 832 of file qgsmapcanvas.cpp.

◆ setLabelingEngineSettings()

void QgsMapCanvas::setLabelingEngineSettings ( const QgsLabelingEngineSettings & settings )

Sets global labeling engine settings in the internal map settings.

Since: QGIS 3.0

Definition at line 2386 of file qgsmapcanvas.cpp.

◆ setLayers()

void QgsMapCanvas::setLayers ( const QList< QgsMapLayer *> & layers )

Sets the list of layers that should be shown in the canvas.

If the map canvas has been associated with a map theme via a call to setTheme(), then any calls to setLayers() are ignored. It is necessary to first clear the theme association by calling setTheme() with an empty string before setLayers() calls can be made.

See also: layers()

Since: QGIS 3.0

Definition at line 323 of file qgsmapcanvas.cpp.

◆ setLayerStyleOverrides()

void QgsMapCanvas::setLayerStyleOverrides ( const QMap< QString, QString > & overrides )

Sets the stored overrides of styles for rendering layers.

If the map canvas has been associated with a map theme via a call to setTheme(), then any calls to setLayerStyleOverrides() are ignored. It is necessary to first clear the theme association by calling setTheme() with an empty string before setLayerStyleOverrides() calls can be made.

See also: layerStyleOverrides()

Since: QGIS 2.12

Definition at line 1896 of file qgsmapcanvas.cpp.

◆ setMagnificationFactor

void QgsMapCanvas::setMagnificationFactor ( double factor )

slot

Sets the factor of magnification to apply to the map canvas.

Indeed, we increase/decrease the DPI of the map settings according to this factor in order to render marker point, labels, ... bigger.

Since: QGIS 2.16

Definition at line 257 of file qgsmapcanvas.cpp.

◆ setMapSettingsFlags()

void QgsMapCanvas::setMapSettingsFlags ( QgsMapSettings::Flags flags )

Resets the flags for the canvas' map settings.

Since: QGIS 3.0

Definition at line 414 of file qgsmapcanvas.cpp.

◆ setMapTool()

void QgsMapCanvas::setMapTool	(	QgsMapTool *	mapTool,
		bool	clean = `false`
	)

Sets the map tool currently being used on the canvas.

Definition at line 1734 of file qgsmapcanvas.cpp.

◆ setMapUpdateInterval()

void QgsMapCanvas::setMapUpdateInterval ( int timeMilliseconds )

Set how often map preview should be updated while it is being rendered (in milliseconds)

Since: QGIS 2.4

Definition at line 469 of file qgsmapcanvas.cpp.

◆ setParallelRenderingEnabled()

void QgsMapCanvas::setParallelRenderingEnabled ( bool enabled )

Set whether the layers are rendered in parallel or sequentially.

Since: QGIS 2.4

Definition at line 459 of file qgsmapcanvas.cpp.

◆ setPreviewJobsEnabled()

void QgsMapCanvas::setPreviewJobsEnabled ( bool enabled )

Sets whether canvas map preview jobs (low priority render jobs which render portions of the view just outside of the canvas extent, to allow preview of these out-of-canvas areas when panning or zooming out the map) are enabled for the canvas.

See also: previewJobsEnabled()

Since: QGIS 3.0

Definition at line 717 of file qgsmapcanvas.cpp.

◆ setPreviewMode()

void QgsMapCanvas::setPreviewMode ( QgsPreviewEffect::PreviewMode mode )

Sets a preview mode for the map canvas.

This setting only has an effect if previewModeEnabled is true.

Parameters

mode	preview mode for the canvas

See also: previewMode; setPreviewModeEnabled; previewModeEnabled

Since: QGIS 2.3

Definition at line 2102 of file qgsmapcanvas.cpp.

◆ setPreviewModeEnabled()

void QgsMapCanvas::setPreviewModeEnabled ( bool previewEnabled )

Enables a preview mode for the map canvas.

Parameters

previewEnabled set to true to enable a preview mode

See also: setPreviewMode

Since: QGIS 2.3

Definition at line 2082 of file qgsmapcanvas.cpp.

◆ setReferencedExtent()

bool QgsMapCanvas::setReferencedExtent ( const QgsReferencedRectangle & extent )

Sets the canvas to the specified extent.

Returns: true if the zoom was successful.

Exceptions

QgsCsException if a transformation error occurred.

Since: QGIS 3.10

Definition at line 883 of file qgsmapcanvas.cpp.

◆ setRenderFlag

void QgsMapCanvas::setRenderFlag ( bool flag )

slot

Sets whether a user has disabled canvas renders via the GUI.

Parameters

flag	set to `false` to indicate that user has disabled renders

See also: renderFlag(); freeze(). freeze() should be used to programmatically halt map updates, while setRenderFlag() should only be used when users disable rendering via GUI.

Definition at line 1927 of file qgsmapcanvas.cpp.

◆ setRotation()

void QgsMapCanvas::setRotation ( double degrees )

Set the rotation of the map canvas in clockwise degrees.

Since: QGIS 2.8

Definition at line 931 of file qgsmapcanvas.cpp.

◆ setScaleLocked

void QgsMapCanvas::setScaleLocked ( bool isLocked )

slot

Lock the scale, so zooming can be performed using magnication.

See also: scaleLocked()

Since: QGIS 2.16

Definition at line 1700 of file qgsmapcanvas.cpp.

◆ setSegmentationTolerance()

void QgsMapCanvas::setSegmentationTolerance ( double tolerance )

Sets the segmentation tolerance applied when rendering curved geometries.

Parameters

tolerance the segmentation tolerance

Definition at line 2350 of file qgsmapcanvas.cpp.

◆ setSegmentationToleranceType()

void QgsMapCanvas::setSegmentationToleranceType ( QgsAbstractGeometry::SegmentationToleranceType type )

Sets segmentation tolerance type (maximum angle or maximum difference between curve and approximation)

Parameters

type	the segmentation tolerance typename

Definition at line 2355 of file qgsmapcanvas.cpp.

◆ setSelectionColor()

void QgsMapCanvas::setSelectionColor ( const QColor & color )

Set color of selected vector features.

Since: QGIS 2.4

Definition at line 1820 of file qgsmapcanvas.cpp.

◆ setSnappingUtils()

void QgsMapCanvas::setSnappingUtils ( QgsSnappingUtils * utils )

Assign an instance of snapping utils to the map canvas.

The instance is not owned by the canvas, so it is possible to use one instance in multiple canvases.

For main canvas in QGIS, do not associate a different instance from the existing one (it is updated from the project's snapping configuration).

Since: QGIS 2.8

Definition at line 2133 of file qgsmapcanvas.cpp.

◆ setTheme()

void QgsMapCanvas::setTheme ( const QString & theme )

Sets a map theme to show in the canvas.

The theme name must match a theme present in the associated project's QgsMapThemeCollection.

When the canvas is associated to a map theme, it will automatically follow the layer selection and layer styles from that theme. Calls to setLayers() or setLayerStyleOverrides() will have no effect, and canvases associated with a QgsLayerTreeMapCanvasBridge will no longer synchronize their state with the layer tree. In these cases it is necessary to call setTheme() with an empty string to clear the theme association and allow map updates with setLayers(), setLayerStyleOverrides(), or via QgsLayerTreeMapCanvasBridge.

If an empty string is passed then the current theme association will be cleared.

See also: theme()

Since: QGIS 3.0

Definition at line 1906 of file qgsmapcanvas.cpp.

◆ setWheelFactor()

void QgsMapCanvas::setWheelFactor ( double factor )

Sets wheel zoom factor (should be greater than 1)

Definition at line 1659 of file qgsmapcanvas.cpp.

◆ snappingUtils()

QgsSnappingUtils * QgsMapCanvas::snappingUtils ( ) const

Returns snapping utility class that is associated with map canvas.

If no snapping utils instance has been associated previously, an internal will be created for convenience (so map tools do not need to test for existence of the instance).

Main canvas in QGIS returns an instance which is always up-to-date with the project's snapping configuration.

Since: QGIS 2.8

Definition at line 2122 of file qgsmapcanvas.cpp.

◆ stopRendering

void QgsMapCanvas::stopRendering ( )

slot

stop rendering (if there is any right now)

Since: QGIS 2.4

Definition at line 736 of file qgsmapcanvas.cpp.

◆ theme()

QString QgsMapCanvas::theme ( ) const

inline

Returns the map's theme shown in the canvas, if set.

See also: setTheme()

Since: QGIS 3.0

Definition at line 437 of file qgsmapcanvas.h.

◆ themeChanged

void QgsMapCanvas::themeChanged ( const QString & theme )

signal

Emitted when the canvas has been assigned a different map theme.

See also: setTheme()

Since: QGIS 3.0

◆ transformContextChanged

void QgsMapCanvas::transformContextChanged ( )

signal

Emitted when the canvas transform context is changed.

Since: QGIS 3.0

◆ unsetMapTool()

void QgsMapCanvas::unsetMapTool ( QgsMapTool * mapTool )

Unset the current map tool or last non zoom tool.

This is called from destructor of map tools to make sure that this map tool won't be used any more. You don't have to call it manually, QgsMapTool takes care of it.

Definition at line 1774 of file qgsmapcanvas.cpp.

◆ updateCanvasItemPositions

void QgsMapCanvas::updateCanvasItemPositions ( )

protectedslot

called on resize or changed extent to notify canvas items to change their rectangle

Definition at line 1601 of file qgsmapcanvas.cpp.

◆ updateScale()

void QgsMapCanvas::updateScale ( )

Emits signal scaleChanged to update scale in main window.

Definition at line 944 of file qgsmapcanvas.cpp.

◆ waitWhileRendering()

void QgsMapCanvas::waitWhileRendering ( )

Blocks until the rendering job has finished.

In almost all cases you do NOT want to call this, as it will hang the UI until the rendering job is complete. It's included in API solely for unit testing and standalone Python scripts.

Since: QGIS 3.0

Definition at line 2342 of file qgsmapcanvas.cpp.

◆ wheelEvent()

void QgsMapCanvas::wheelEvent ( QWheelEvent * e )

overrideprotected

Definition at line 1616 of file qgsmapcanvas.cpp.

◆ writeProject

void QgsMapCanvas::writeProject ( QDomDocument & doc )

slot

called to write map canvas settings to project

Definition at line 2197 of file qgsmapcanvas.cpp.

◆ xyCoordinates

void QgsMapCanvas::xyCoordinates ( const QgsPointXY & p )

signal

Emits current mouse position.

Note: changed in 1.3

◆ zoomByFactor()

void QgsMapCanvas::zoomByFactor	(	double	scaleFactor,
		const QgsPointXY *	center = `nullptr`
	)

Zoom with the factor supplied.

Factor > 1 zooms out, interval (0,1) zooms in If point is given, re-center on it

Definition at line 2232 of file qgsmapcanvas.cpp.

◆ zoomIn

void QgsMapCanvas::zoomIn ( )

slot

Zoom in with fixed factor.

Definition at line 1664 of file qgsmapcanvas.cpp.

◆ zoomLastStatusChanged

void QgsMapCanvas::zoomLastStatusChanged ( bool )

signal

Emitted when zoom last status changed.

◆ zoomNextStatusChanged

void QgsMapCanvas::zoomNextStatusChanged ( bool )

signal

Emitted when zoom next status changed.

◆ zoomOut

void QgsMapCanvas::zoomOut ( )

slot

Zoom out with fixed factor.

Definition at line 1670 of file qgsmapcanvas.cpp.

◆ zoomScale()

void QgsMapCanvas::zoomScale ( double scale )

Zooms the canvas to a specific scale.

The scale value indicates the scale denominator, e.g. 1000.0 for a 1:1000 map.

Definition at line 1676 of file qgsmapcanvas.cpp.

◆ zoomToFeatureExtent()

void QgsMapCanvas::zoomToFeatureExtent ( QgsRectangle & rect )

Zooms to feature extent.

Adds a small margin around the extent and does a pan if rect is empty (point extent)

Definition at line 1060 of file qgsmapcanvas.cpp.

◆ zoomToFeatureIds()

void QgsMapCanvas::zoomToFeatureIds	(	QgsVectorLayer *	layer,
		const QgsFeatureIds &	ids
	)

Set canvas extent to the bounding box of a set of features.

Parameters

layer	the vector layer
ids	the feature ids

Definition at line 1084 of file qgsmapcanvas.cpp.

◆ zoomToFullExtent()

void QgsMapCanvas::zoomToFullExtent ( )

Zoom to the full extent of all layers.

Definition at line 950 of file qgsmapcanvas.cpp.

◆ zoomToNextExtent()

void QgsMapCanvas::zoomToNextExtent ( )

Zoom to the next extent (view)

Definition at line 981 of file qgsmapcanvas.cpp.

◆ zoomToPreviousExtent()

void QgsMapCanvas::zoomToPreviousExtent ( )

Zoom to the previous extent (view)

Definition at line 965 of file qgsmapcanvas.cpp.

◆ zoomToSelected

void QgsMapCanvas::zoomToSelected ( QgsVectorLayer * layer = nullptr )

slot

Zoom to the extent of the selected features of provided (vector) layer.

Parameters

layer optionally specify different than current layer

Definition at line 1006 of file qgsmapcanvas.cpp.

◆ zoomWithCenter()

void QgsMapCanvas::zoomWithCenter	(	int	x,
		int	y,
		bool	zoomIn
	)

Zooms in/out with a given center.

Definition at line 1681 of file qgsmapcanvas.cpp.

Friends And Related Function Documentation

◆ TestQgsMapCanvas

friend class TestQgsMapCanvas

friend

Definition at line 1076 of file qgsmapcanvas.h.

Member Data Documentation

◆ mCanvasProperties

std::unique_ptr<CanvasProperties> QgsMapCanvas::mCanvasProperties

protected

Handle pattern for implementation object.

Definition at line 904 of file qgsmapcanvas.h.

Property Documentation

◆ previewJobsEnabled

bool QgsMapCanvas::previewJobsEnabled

readwrite

Definition at line 89 of file qgsmapcanvas.h.

◆ theme

QString QgsMapCanvas::theme

readwrite

Definition at line 88 of file qgsmapcanvas.h.

The documentation for this class was generated from the following files:

/build/qgis-3.10.0+15buster/src/gui/qgsmapcanvas.h
/build/qgis-3.10.0+15buster/src/gui/qgsmapcanvas.cpp

Classes

Public Slots

Signals

Public Member Functions

Protected Slots

Protected Member Functions

Protected Attributes

Properties

Friends

Detailed Description

Constructor & Destructor Documentation

◆ QgsMapCanvas()

◆ ~QgsMapCanvas()

Member Function Documentation

◆ annotationItems()

◆ annotationsVisible()

◆ antiAliasingEnabled()

◆ canvasColor()

◆ canvasColorChanged

◆ center()

◆ clearCache()

◆ clearExtentHistory()

◆ currentLayer()

◆ currentLayerChanged

◆ defaultExpressionContextScope()

◆ destinationCrsChanged

◆ dragEnterEvent()

◆ dropEvent()

◆ enableAntiAliasing()

◆ enableMapTileRendering()

◆ event()

◆ expressionContextScope() [1/2]

◆ expressionContextScope() [2/2]

◆ extent()

◆ extentsChanged

◆ flashFeatureIds()

◆ flashGeometries()

◆ freeze()

◆ fullExtent()

◆ getCoordinateTransform()

◆ isCachingEnabled()

◆ isDrawing()

◆ isFrozen()

◆ isParallelRenderingEnabled()

◆ keyPressed

◆ keyPressEvent()

◆ keyReleased

◆ keyReleaseEvent()

◆ labelingEngineSettings()

◆ labelingResults()

◆ layer()

◆ layerCount()

◆ layers()

◆ layersChanged

◆ layerStateChange

◆ layerStyleOverrides()

◆ layerStyleOverridesChanged

◆ magnificationChanged

◆ magnificationFactor()

◆ mapCanvasRefreshed

◆ mapSettings()

◆ mapTool()

◆ mapToolSet

◆ mapUnits()

◆ mapUnitsPerPixel()

◆ mapUpdateInterval()

◆ messageEmitted

◆ mouseDoubleClickEvent()

◆ mouseLastXY()

◆ mouseMoveEvent()

◆ mousePressEvent()

◆ mouseReleaseEvent()

◆ moveCanvasContents()

◆ paintEvent()

◆ panAction()

◆ panActionEnd()

◆ panToFeatureIds()

◆ panToSelected()

◆ previewJobsEnabled()

◆ previewMode()