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QgsMapCanvas Class Reference

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

#include <qgsmapcanvas.h>

Classes

class  CanvasProperties

Public Types

enum  WheelAction { WheelZoom, WheelZoomAndRecenter, WheelZoomToMouseCursor, WheelNothing }

Public Slots

static void enableRotation (bool enabled)
 change canvas rotation support
void getDatumTransformInfo (const QgsMapLayer *ml, const QString &srcAuthId, const QString &destAuthId)
 ask user about datum transformation
bool hasCrsTransformEnabled ()
 A simple helper method to find out if on the fly projections are enabled or not.
void layerCrsChange ()
 This slot is connected to the layer's CRS change.
void layerStateChange ()
 This slot is connected to the visibility change of one or more layers.
void readProject (const QDomDocument &)
 called to read map canvas settings from project
void refresh ()
 Repaints the canvas map.
bool renderFlag ()
 State of render suppression flag.
static bool rotationEnabled ()
 return if canvas rotation is enabled
void saveAsImage (QString theFileName, QPixmap *QPixmap=0, QString="PNG")
 Save the convtents of the map canvas to disk as an image.
void selectionChangedSlot ()
 Receives signal about selection change, and pass it on with layer info.
void setRenderFlag (bool theFlag)
 Whether to suppress rendering or not.
Q_DECL_DEPRECATED void showError (QgsMapLayer *mapLayer)
void stopRendering ()
 stop rendering (if there is any right now)
Q_DECL_DEPRECATED void updateMap ()
void writeProject (QDomDocument &)
 called to write map canvas settings to project

Signals

void currentLayerChanged (QgsMapLayer *layer)
 Emitted when the current layer is changed.
void destinationCrsChanged ()
 Emitted when map CRS has changed.
void extentsChanged ()
 Emitted when the extents of the map change.
void hasCrsTransformEnabledChanged (bool flag)
 Emitted when on-the-fly projection has been turned on/off.
void keyPressed (QKeyEvent *e)
 Emit key press event.
void keyReleased (QKeyEvent *e)
 Emit key release event.
void layersChanged ()
 Emitted when a new set of layers has been received.
void mapCanvasRefreshed ()
 Emitted when canvas finished a refresh request.
void mapToolSet (QgsMapTool *tool)
 Emit map tool changed event.
void mapToolSet (QgsMapTool *newTool, QgsMapTool *oldTool)
 Emit map tool changed with the old tool.
void mapUnitsChanged ()
 Emmitted when map units are changed.
void renderComplete (QPainter *)
 Emitted when the canvas has rendered.
void renderStarting ()
 Emitted when the canvas is about to be rendered.
void rotationChanged (double)
 Emitted when the rotation of the map changes.
void scaleChanged (double)
 Emitted when the scale of the map changes.
void selectionChanged (QgsMapLayer *layer)
 Emitted when selection in any layer gets changed.
Q_DECL_DEPRECATED void setProgress (int, int)
 Let the owner know how far we are with render operations.
void xyCoordinates (const QgsPoint &p)
 emits current mouse position
void zoomLastStatusChanged (bool)
 Emitted when zoom last status changed.
void zoomNextStatusChanged (bool)
 Emitted when zoom next status changed.

Public Member Functions

 QgsMapCanvas (QWidget *parent=0, const char *name=0)
 Constructor.
 ~QgsMapCanvas ()
 Destructor.
bool antiAliasingEnabled () const
 true if antialising is enabled
virtual QColor canvasColor () const
 Read property of QColor bgColor.
Q_DECL_DEPRECATED QPaintDevice & canvasPaintDevice ()
 Accessor for the canvas paint device.
QgsPoint center () const
 Get map center, in geographical coordinates.
Q_DECL_DEPRECATED void clear ()
 Clear the map canvas.
void clearCache ()
 Make sure to remove any rendered images from cache (does nothing if cache is not enabled)
void clearExtentHistory ()
QgsMapLayercurrentLayer ()
 returns current layer (set by legend widget)
void enableAntiAliasing (bool theFlag)
 used to determine if anti-aliasing is enabled or not
void enableOverviewMode (QgsMapOverviewCanvas *overview)
QgsRectangle extent () const
 Returns the current zoom exent of the map canvas.
void freeze (bool frz=true)
QgsRectangle fullExtent () const
 Returns the combined exent for all layers on the map canvas.
const QgsMapToPixelgetCoordinateTransform ()
 Get the current coordinate transform.
bool isCachingEnabled () const
 Check whether images of rendered layers are curerently being cached.
Q_DECL_DEPRECATED bool isDirty () const
 Return the state of the canvas (dirty or not)
bool isDrawing ()
 Find out whether rendering is in progress.
bool isFrozen ()
bool isParallelRenderingEnabled () const
 Check whether the layers are rendered in parallel or sequentially.
const QgsLabelingResultslabelingResults () const
 Get access to the labeling results (may be null)
QgsMapLayerlayer (int index)
 return the map layer at position index in the layer stack
int layerCount () const
 return number of layers on the map
QList< QgsMapLayer * > layers () const
 return list of layers within map canvas.
QgsMapCanvasMapmap ()
Q_DECL_DEPRECATED QgsMapRenderermapRenderer ()
const QgsMapSettingsmapSettings () const
 Get access to properties used for map rendering.
QgsMapToolmapTool ()
 Returns the currently active tool.
QGis::UnitType mapUnits () const
 Get the current canvas map units.
double mapUnitsPerPixel () const
 Returns the mapUnitsPerPixel (map units per pixel) for the canvas.
int mapUpdateInterval () const
 Find out how often map preview should be updated while it is being rendered (in milliseconds)
QPoint mouseLastXY ()
 returns last position of mouse cursor
void panAction (QMouseEvent *event)
 Called when mouse is moving and pan is activated.
void panActionEnd (QPoint releasePoint)
 Ends pan action and redraws the canvas.
void panToSelected (QgsVectorLayer *layer=NULL)
 Pan to the selected features of current (vector) layer keeping same extent.
QgsPreviewEffect::PreviewMode previewMode () const
 Returns the current preview mode for the map canvas.
bool previewModeEnabled () const
 Returns whether a preview mode is enabled for the map canvas.
double rotation () const
 Get the current map canvas rotation in clockwise degrees.
double scale ()
 Get the last reported scale of the canvas.
void setCachingEnabled (bool enabled)
 Set whether to cache images of rendered layers.
virtual void setCanvasColor (const QColor &_newVal)
 Write property of QColor bgColor.
void setCenter (const QgsPoint &center)
 Set the center of the map canvas, in geographical coordinates.
void setCrsTransformEnabled (bool enabled)
 sets whether to use projections for this layer set
void setCurrentLayer (QgsMapLayer *layer)
void setDestinationCrs (const QgsCoordinateReferenceSystem &crs)
 sets destination coordinate reference system
Q_DECL_DEPRECATED void setDirty (bool _dirty)
 Flag the canvas as dirty and needed a refresh.
void setExtent (const QgsRectangle &r)
 Set the extent of the map canvas.
void setLayerSet (QList< QgsMapCanvasLayer > &layers)
void setMapTool (QgsMapTool *mapTool)
 Sets the map tool currently being used on the canvas.
void setMapUnits (QGis::UnitType mapUnits)
 Set map units (needed by project properties dialog)
void setMapUpdateInterval (int timeMiliseconds)
 Set how often map preview should be updated while it is being rendered (in milliseconds)
void setParallelRenderingEnabled (bool enabled)
 Set whether the layers are rendered in parallel or sequentially.
void setPreviewMode (QgsPreviewEffect::PreviewMode mode)
 Sets a preview mode for the map canvas.
void setPreviewModeEnabled (bool previewEnabled)
 Enables a preview mode for the map canvas.
void setRotation (double degrees)
 Set the rotation of the map canvas in clockwise degrees.
void setSelectionColor (const QColor &color)
 Set color of selected vector features.
void setSnappingUtils (QgsSnappingUtils *utils)
 Assign an instance of snapping utils to the map canvas.
void setWheelAction (WheelAction action, double factor=2)
 set wheel action and zoom factor (should be greater than 1)
QgsSnappingUtilssnappingUtils () const
 Return snapping utility class that is associated with map canvas.
void unsetMapTool (QgsMapTool *mapTool)
 Unset the current map tool or last non zoom tool.
Q_DECL_DEPRECATED void updateFullExtent ()
 Updates the full extent.
void updateOverview ()
void updateScale ()
 Emits signal scaleChanged to update scale in main window.
Q_DECL_DEPRECATED void useImageToRender (bool theFlag)
 Select which Qt class to render with.
void zoomByFactor (double scaleFactor, const QgsPoint *center=0)
 Zoom with the factor supplied.
void zoomIn ()
 Zoom in with fixed factor.
void zoomOut ()
 Zoom out with fixed factor.
void zoomScale (double scale)
 Zoom to a specific scale.
void zoomToFullExtent ()
 Zoom to the full extent of all layers.
void zoomToNextExtent ()
 Zoom to the next extent (view)
void zoomToPreviousExtent ()
 Zoom to the previous extent (view)
void zoomToSelected (QgsVectorLayer *layer=NULL)
 Zoom to the extent of the selected features of current (vector) layer.
void zoomWithCenter (int x, int y, bool zoomIn)
 Zooms in/out with a given center.

Protected Member Functions

void dragEnterEvent (QDragEnterEvent *e) override
 Overridden drag enter event.
void keyPressEvent (QKeyEvent *e) override
 Overridden key press event.
void keyReleaseEvent (QKeyEvent *e) override
 Overridden key release event.
void mouseDoubleClickEvent (QMouseEvent *e) override
 Overridden mouse double click event.
void mouseMoveEvent (QMouseEvent *e) override
 Overridden mouse move event.
void mousePressEvent (QMouseEvent *e) override
 Overridden mouse press event.
void mouseReleaseEvent (QMouseEvent *e) override
 Overridden mouse release event.
void moveCanvasContents (bool reset=false)
 called when panning is in action, reset indicates end of panning
void paintEvent (QPaintEvent *e) override
 Overridden paint event.
void resizeEvent (QResizeEvent *e) override
 Overridden resize event.
void updateCanvasItemPositions ()
 called on resize or changed extent to notify canvas items to change their rectangle
void updateDatumTransformEntries ()
 Make sure the datum transform store is properly populated.
void wheelEvent (QWheelEvent *e) override
 Overridden mouse wheel event.

Protected Attributes

QScopedPointer< CanvasPropertiesmCanvasProperties
 Handle pattern for implementation object.

Detailed Description

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

Definition at line 105 of file qgsmapcanvas.h.

Member Enumeration Documentation

Enumerator:
WheelZoom 
WheelZoomAndRecenter 
WheelZoomToMouseCursor 
WheelNothing 

Definition at line 111 of file qgsmapcanvas.h.

Constructor & Destructor Documentation

QgsMapCanvas::QgsMapCanvas ( QWidget *  parent = 0,
const char *  name = 0 
)

Constructor.

Definition at line 184 of file qgsmapcanvas.cpp.

QgsMapCanvas::~QgsMapCanvas ( )

Destructor.

Definition at line 268 of file qgsmapcanvas.cpp.

Member Function Documentation

bool QgsMapCanvas::antiAliasingEnabled ( ) const
inline

true if antialising is enabled

Definition at line 335 of file qgsmapcanvas.h.

QColor QgsMapCanvas::canvasColor ( ) const
virtual

Read property of QColor bgColor.

Definition at line 1546 of file qgsmapcanvas.cpp.

QPaintDevice & QgsMapCanvas::canvasPaintDevice ( )

Accessor for the canvas paint device.

Deprecated:
since 2.4

Definition at line 1605 of file qgsmapcanvas.cpp.

QgsPoint QgsMapCanvas::center ( ) const

Get map center, in geographical coordinates.

Note
added in 2.8

Definition at line 912 of file qgsmapcanvas.cpp.

void QgsMapCanvas::clear ( )

Clear the map canvas.

Deprecated:
since 2.4 - use refresh() - clear does the same thing

Definition at line 950 of file qgsmapcanvas.cpp.

void QgsMapCanvas::clearCache ( )

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

Note
added in 2.4

Definition at line 573 of file qgsmapcanvas.cpp.

void QgsMapCanvas::clearExtentHistory ( )

Definition at line 1008 of file qgsmapcanvas.cpp.

QgsMapLayer * QgsMapCanvas::currentLayer ( )

returns current layer (set by legend widget)

Definition at line 610 of file qgsmapcanvas.cpp.

void QgsMapCanvas::currentLayerChanged ( QgsMapLayer layer)
signal

Emitted when the current layer is changed.

Note
added in 2.8
void QgsMapCanvas::destinationCrsChanged ( )
signal

Emitted when map CRS has changed.

Note
added in 2.4
void QgsMapCanvas::dragEnterEvent ( QDragEnterEvent *  e)
overrideprotected

Overridden drag enter event.

Definition at line 1919 of file qgsmapcanvas.cpp.

void QgsMapCanvas::enableAntiAliasing ( bool  theFlag)

used to determine if anti-aliasing is enabled or not

Definition at line 307 of file qgsmapcanvas.cpp.

void QgsMapCanvas::enableOverviewMode ( QgsMapOverviewCanvas overview)

Definition at line 466 of file qgsmapcanvas.cpp.

void QgsMapCanvas::enableRotation ( bool  enabled)
staticslot

change canvas rotation support

Note
added in 2.8

Definition at line 1959 of file qgsmapcanvas.cpp.

QgsRectangle QgsMapCanvas::extent ( ) const

Returns the current zoom exent of the map canvas.

Definition at line 834 of file qgsmapcanvas.cpp.

void QgsMapCanvas::extentsChanged ( )
signal

Emitted when the extents of the map change.

void QgsMapCanvas::freeze ( bool  frz = 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
frzBoolean specifying if the canvas should be frozen (true) or thawed (false). Default is true.

Definition at line 1594 of file qgsmapcanvas.cpp.

QgsRectangle QgsMapCanvas::fullExtent ( ) const

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

Definition at line 839 of file qgsmapcanvas.cpp.

const QgsMapToPixel * QgsMapCanvas::getCoordinateTransform ( )

Get the current coordinate transform.

Definition at line 373 of file qgsmapcanvas.cpp.

void QgsMapCanvas::getDatumTransformInfo ( const QgsMapLayer ml,
const QString &  srcAuthId,
const QString &  destAuthId 
)
slot

ask user about datum transformation

Ask user which datum transform to use.

Definition at line 1835 of file qgsmapcanvas.cpp.

bool QgsMapCanvas::hasCrsTransformEnabled ( )
slot

A simple helper method to find out if on the fly projections are enabled or not.

Definition at line 1019 of file qgsmapcanvas.cpp.

void QgsMapCanvas::hasCrsTransformEnabledChanged ( bool  flag)
signal

Emitted when on-the-fly projection has been turned on/off.

Note
added in 2.4
bool QgsMapCanvas::isCachingEnabled ( ) const

Check whether images of rendered layers are curerently being cached.

Note
added in 2.4

Definition at line 568 of file qgsmapcanvas.cpp.

bool QgsMapCanvas::isDirty ( ) const

Return the state of the canvas (dirty or not)

Deprecated:
since 2.4 - dirty flag is not kept anymore - always returns false

Definition at line 358 of file qgsmapcanvas.cpp.

bool QgsMapCanvas::isDrawing ( )

Find out whether rendering is in progress.

Definition at line 365 of file qgsmapcanvas.cpp.

bool QgsMapCanvas::isFrozen ( )

Accessor for frozen status of canvas

Definition at line 1599 of file qgsmapcanvas.cpp.

bool QgsMapCanvas::isParallelRenderingEnabled ( ) const

Check whether the layers are rendered in parallel or sequentially.

Note
added in 2.4

Definition at line 584 of file qgsmapcanvas.cpp.

void QgsMapCanvas::keyPressed ( QKeyEvent *  e)
signal

Emit key press event.

void QgsMapCanvas::keyPressEvent ( QKeyEvent *  e)
overrideprotected

Overridden key press event.

Definition at line 1089 of file qgsmapcanvas.cpp.

void QgsMapCanvas::keyReleased ( QKeyEvent *  e)
signal

Emit key release event.

void QgsMapCanvas::keyReleaseEvent ( QKeyEvent *  e)
overrideprotected

Overridden key release event.

Definition at line 1198 of file qgsmapcanvas.cpp.

const QgsLabelingResults * QgsMapCanvas::labelingResults ( ) const

Get access to the labeling results (may be null)

Note
added in 2.4

Definition at line 547 of file qgsmapcanvas.cpp.

QgsMapLayer * QgsMapCanvas::layer ( int  index)

return the map layer at position index in the layer stack

Definition at line 331 of file qgsmapcanvas.cpp.

int QgsMapCanvas::layerCount ( ) const

return number of layers on the map

Definition at line 1556 of file qgsmapcanvas.cpp.

void QgsMapCanvas::layerCrsChange ( )
slot

This slot is connected to the layer's CRS change.

Definition at line 1583 of file qgsmapcanvas.cpp.

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

return list of layers within map canvas.

Definition at line 1562 of file qgsmapcanvas.cpp.

void QgsMapCanvas::layersChanged ( )
signal

Emitted when a new set of layers has been received.

void QgsMapCanvas::layerStateChange ( )
slot

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

Definition at line 1575 of file qgsmapcanvas.cpp.

QgsMapCanvasMap * QgsMapCanvas::map ( )
Deprecated:
since 2.4 - there could be more than just one "map" items

Definition at line 320 of file qgsmapcanvas.cpp.

void QgsMapCanvas::mapCanvasRefreshed ( )
signal

Emitted when canvas finished a refresh request.

QgsMapRenderer * QgsMapCanvas::mapRenderer ( )
Deprecated:
since 2.4 - use mapSettings() for anything related to current renderer settings / SIP: removed /Transfer/ because it crashes after few calls to iface.mapCanvas().mapRenderer().hasCrsTransformEnabled() / and in fact there is no transfer of ownership from c++ to python! / Actually the problem comes from the fact that "hasCrsTransformEnabled" is both a signal and a normal method / /KeepReference/ is necessary because otherwise mapRenderer().hasCrsTransformEnabled() was crashing

Definition at line 325 of file qgsmapcanvas.cpp.

const QgsMapSettings & QgsMapCanvas::mapSettings ( ) const

Get access to properties used for map rendering.

Note
added in 2.4

Definition at line 491 of file qgsmapcanvas.cpp.

QgsMapTool * QgsMapCanvas::mapTool ( )

Returns the currently active tool.

Definition at line 1684 of file qgsmapcanvas.cpp.

void QgsMapCanvas::mapToolSet ( QgsMapTool tool)
signal

Emit map tool changed event.

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

Emit map tool changed with the old tool.

Note
added in 2.3
QGis::UnitType QgsMapCanvas::mapUnits ( ) const

Get the current canvas map units.

Definition at line 1634 of file qgsmapcanvas.cpp.

void QgsMapCanvas::mapUnitsChanged ( )
signal

Emmitted when map units are changed.

Note
added in 2.4
double QgsMapCanvas::mapUnitsPerPixel ( ) const

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

Definition at line 1612 of file qgsmapcanvas.cpp.

int QgsMapCanvas::mapUpdateInterval ( ) const

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

Note
added in 2.4

Definition at line 594 of file qgsmapcanvas.cpp.

void QgsMapCanvas::mouseDoubleClickEvent ( QMouseEvent *  e)
overrideprotected

Overridden mouse double click event.

Definition at line 1230 of file qgsmapcanvas.cpp.

QPoint QgsMapCanvas::mouseLastXY ( )

returns last position of mouse cursor

Definition at line 1730 of file qgsmapcanvas.cpp.

void QgsMapCanvas::mouseMoveEvent ( QMouseEvent *  e)
overrideprotected

Overridden mouse move event.

Definition at line 1447 of file qgsmapcanvas.cpp.

void QgsMapCanvas::mousePressEvent ( QMouseEvent *  e)
overrideprotected

Overridden mouse press event.

Definition at line 1240 of file qgsmapcanvas.cpp.

void QgsMapCanvas::mouseReleaseEvent ( QMouseEvent *  e)
overrideprotected

Overridden mouse release event.

Definition at line 1269 of file qgsmapcanvas.cpp.

void QgsMapCanvas::moveCanvasContents ( bool  reset = false)
protected

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

Definition at line 1716 of file qgsmapcanvas.cpp.

void QgsMapCanvas::paintEvent ( QPaintEvent *  e)
overrideprotected

Overridden paint event.

Definition at line 1336 of file qgsmapcanvas.cpp.

void QgsMapCanvas::panAction ( QMouseEvent *  event)

Called when mouse is moving and pan is activated.

Definition at line 1708 of file qgsmapcanvas.cpp.

void QgsMapCanvas::panActionEnd ( QPoint  releasePoint)

Ends pan action and redraws the canvas.

Definition at line 1689 of file qgsmapcanvas.cpp.

void QgsMapCanvas::panToSelected ( QgsVectorLayer layer = NULL)

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

Definition at line 1066 of file qgsmapcanvas.cpp.

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
Note
added in 2.3

Definition at line 1765 of file qgsmapcanvas.cpp.

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
Note
added in 2.3

Definition at line 1745 of file qgsmapcanvas.cpp.

void QgsMapCanvas::readProject ( const QDomDocument &  doc)
slot

called to read map canvas settings from project

Definition at line 1791 of file qgsmapcanvas.cpp.

void QgsMapCanvas::refresh ( )
slot

Repaints the canvas map.

Definition at line 616 of file qgsmapcanvas.cpp.

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
bool QgsMapCanvas::renderFlag ( )
inlineslot

State of render suppression flag.

Definition at line 419 of file qgsmapcanvas.h.

void QgsMapCanvas::renderStarting ( )
signal

Emitted when the canvas is about to be rendered.

void QgsMapCanvas::resizeEvent ( QResizeEvent *  e)
overrideprotected

Overridden resize event.

Definition at line 1312 of file qgsmapcanvas.cpp.

double QgsMapCanvas::rotation ( ) const

Get the current map canvas rotation in clockwise degrees.

Note
added in 2.8

Definition at line 919 of file qgsmapcanvas.cpp.

void QgsMapCanvas::rotationChanged ( double  )
signal

Emitted when the rotation of the map changes.

Note
added in 2.8
bool QgsMapCanvas::rotationEnabled ( )
staticslot

return if canvas rotation is enabled

Note
added in 2.8

Definition at line 1954 of file qgsmapcanvas.cpp.

void QgsMapCanvas::saveAsImage ( QString  theFileName,
QPixmap *  QPixmap = 0,
QString  theFormat = "PNG" 
)
slot

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

Definition at line 781 of file qgsmapcanvas.cpp.

double QgsMapCanvas::scale ( )

Get the last reported scale of the canvas.

Definition at line 347 of file qgsmapcanvas.cpp.

void QgsMapCanvas::scaleChanged ( double  )
signal

Emitted when the scale of the map changes.

void QgsMapCanvas::selectionChanged ( QgsMapLayer layer)
signal

Emitted when selection in any layer gets changed.

void QgsMapCanvas::selectionChangedSlot ( )
slot

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

Definition at line 1911 of file qgsmapcanvas.cpp.

void QgsMapCanvas::setCachingEnabled ( bool  enabled)

Set whether to cache images of rendered layers.

Note
added in 2.4

Definition at line 552 of file qgsmapcanvas.cpp.

void QgsMapCanvas::setCanvasColor ( const QColor &  theColor)
virtual

Write property of QColor bgColor.

Definition at line 1528 of file qgsmapcanvas.cpp.

void QgsMapCanvas::setCenter ( const QgsPoint center)

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

Note
added in 2.8

Definition at line 899 of file qgsmapcanvas.cpp.

void QgsMapCanvas::setCrsTransformEnabled ( bool  enabled)

sets whether to use projections for this layer set

Note
added in 2.4

Definition at line 496 of file qgsmapcanvas.cpp.

void QgsMapCanvas::setCurrentLayer ( QgsMapLayer layer)

Definition at line 341 of file qgsmapcanvas.cpp.

void QgsMapCanvas::setDestinationCrs ( const QgsCoordinateReferenceSystem crs)

sets destination coordinate reference system

Note
added in 2.4

Definition at line 510 of file qgsmapcanvas.cpp.

void QgsMapCanvas::setDirty ( bool  _dirty)

Flag the canvas as dirty and needed a refresh.

Deprecated:
since 2.4 - use refresh() to trigger a refresh (clients should not decide explicitly whether canvas is dirty or not)

Definition at line 352 of file qgsmapcanvas.cpp.

void QgsMapCanvas::setExtent ( const QgsRectangle r)

Set the extent of the map canvas.

Definition at line 845 of file qgsmapcanvas.cpp.

void QgsMapCanvas::setLayerSet ( QList< QgsMapCanvasLayer > &  layers)

Definition at line 378 of file qgsmapcanvas.cpp.

void QgsMapCanvas::setMapTool ( QgsMapTool mapTool)

Sets the map tool currently being used on the canvas.

Definition at line 1473 of file qgsmapcanvas.cpp.

void QgsMapCanvas::setMapUnits ( QGis::UnitType  mapUnits)

Set map units (needed by project properties dialog)

Definition at line 1618 of file qgsmapcanvas.cpp.

void QgsMapCanvas::setMapUpdateInterval ( int  timeMiliseconds)

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

Note
added in 2.4

Definition at line 589 of file qgsmapcanvas.cpp.

void QgsMapCanvas::setParallelRenderingEnabled ( bool  enabled)

Set whether the layers are rendered in parallel or sequentially.

Note
added in 2.4

Definition at line 579 of file qgsmapcanvas.cpp.

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
modepreview mode for the canvas
See Also
previewMode
setPreviewModeEnabled
previewModeEnabled
Note
added in 2.3

Definition at line 1755 of file qgsmapcanvas.cpp.

void QgsMapCanvas::setPreviewModeEnabled ( bool  previewEnabled)

Enables a preview mode for the map canvas.

Parameters
previewEnabledset to true to enable a preview mode
See Also
setPreviewMode
Note
added in 2.3

Definition at line 1735 of file qgsmapcanvas.cpp.

Q_DECL_DEPRECATED void QgsMapCanvas::setProgress ( int  ,
int   
)
signal

Let the owner know how far we are with render operations.

Deprecated:
since 2.4 - already unused in 2.0 anyway
void QgsMapCanvas::setRenderFlag ( bool  theFlag)
slot

Whether to suppress rendering or not.

Definition at line 1640 of file qgsmapcanvas.cpp.

void QgsMapCanvas::setRotation ( double  degrees)

Set the rotation of the map canvas in clockwise degrees.

Note
added in 2.8

Definition at line 924 of file qgsmapcanvas.cpp.

void QgsMapCanvas::setSelectionColor ( const QColor &  color)

Set color of selected vector features.

Note
added in 2.4

Definition at line 1551 of file qgsmapcanvas.cpp.

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).

Note
added in 2.8

Definition at line 1786 of file qgsmapcanvas.cpp.

void QgsMapCanvas::setWheelAction ( WheelAction  action,
double  factor = 2 
)

set wheel action and zoom factor (should be greater than 1)

Definition at line 1414 of file qgsmapcanvas.cpp.

void QgsMapCanvas::showError ( QgsMapLayer mapLayer)
slot
Deprecated:
since 2.4 - does nothing - errors are reported by different means

Definition at line 1725 of file qgsmapcanvas.cpp.

QgsSnappingUtils * QgsMapCanvas::snappingUtils ( ) const

Return 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.

Note
added in 2.8

Definition at line 1775 of file qgsmapcanvas.cpp.

void QgsMapCanvas::stopRendering ( )
slot

stop rendering (if there is any right now)

Note
added in 2.4

Definition at line 765 of file qgsmapcanvas.cpp.

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 manualy, QgsMapTool takes care of it.

Definition at line 1510 of file qgsmapcanvas.cpp.

void QgsMapCanvas::updateCanvasItemPositions ( )
protected

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

Definition at line 1343 of file qgsmapcanvas.cpp.

void QgsMapCanvas::updateDatumTransformEntries ( )
protected

Make sure the datum transform store is properly populated.

Definition at line 1660 of file qgsmapcanvas.cpp.

Q_DECL_DEPRECATED void QgsMapCanvas::updateFullExtent ( )
inline

Updates the full extent.

Deprecated:
since v2.4 - does nothing

Definition at line 268 of file qgsmapcanvas.h.

void QgsMapCanvas::updateMap ( )
slot
Deprecated:
in 2.4 - does nothing - kept for API compatibility

Definition at line 776 of file qgsmapcanvas.cpp.

void QgsMapCanvas::updateOverview ( )

Definition at line 600 of file qgsmapcanvas.cpp.

void QgsMapCanvas::updateScale ( )

Emits signal scaleChanged to update scale in main window.

Definition at line 944 of file qgsmapcanvas.cpp.

void QgsMapCanvas::useImageToRender ( bool  theFlag)

Select which Qt class to render with.

Deprecated:
since 2.4 - does nothing because now we always render to QImage

Definition at line 315 of file qgsmapcanvas.cpp.

void QgsMapCanvas::wheelEvent ( QWheelEvent *  e)
overrideprotected

Overridden mouse wheel event.

Definition at line 1361 of file qgsmapcanvas.cpp.

void QgsMapCanvas::writeProject ( QDomDocument &  doc)
slot

called to write map canvas settings to project

Definition at line 1815 of file qgsmapcanvas.cpp.

void QgsMapCanvas::xyCoordinates ( const QgsPoint p)
signal

emits current mouse position

Note
changed in 1.3
void QgsMapCanvas::zoomByFactor ( double  scaleFactor,
const QgsPoint center = 0 
)

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 1903 of file qgsmapcanvas.cpp.

void QgsMapCanvas::zoomIn ( )

Zoom in with fixed factor.

Definition at line 1420 of file qgsmapcanvas.cpp.

void QgsMapCanvas::zoomLastStatusChanged ( bool  )
signal

Emitted when zoom last status changed.

void QgsMapCanvas::zoomNextStatusChanged ( bool  )
signal

Emitted when zoom next status changed.

void QgsMapCanvas::zoomOut ( )

Zoom out with fixed factor.

Definition at line 1425 of file qgsmapcanvas.cpp.

void QgsMapCanvas::zoomScale ( double  scale)

Zoom to a specific scale.

Definition at line 1430 of file qgsmapcanvas.cpp.

void QgsMapCanvas::zoomToFullExtent ( )

Zoom to the full extent of all layers.

Definition at line 957 of file qgsmapcanvas.cpp.

void QgsMapCanvas::zoomToNextExtent ( )

Zoom to the next extent (view)

Definition at line 991 of file qgsmapcanvas.cpp.

void QgsMapCanvas::zoomToPreviousExtent ( )

Zoom to the previous extent (view)

Definition at line 973 of file qgsmapcanvas.cpp.

void QgsMapCanvas::zoomToSelected ( QgsVectorLayer layer = NULL)

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

Parameters
layeroptionally specify different than current layer

Definition at line 1024 of file qgsmapcanvas.cpp.

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

Zooms in/out with a given center.

Definition at line 1435 of file qgsmapcanvas.cpp.

Member Data Documentation

QScopedPointer<CanvasProperties> QgsMapCanvas::mCanvasProperties
protected

Handle pattern for implementation object.

Definition at line 588 of file qgsmapcanvas.h.


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