QgsMapCanvas Class Reference
[QGIS gui library.]

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

#include <qgsmapcanvas.h>

Collaboration diagram for QgsMapCanvas:

Collaboration graph
[legend]

List of all members.

Public Types

enum  WheelAction { WheelZoom, WheelZoomAndRecenter, WheelZoomToMouseCursor, WheelNothing }

Public Slots

void refresh ()
 Repaints the canvas map.
void selectionChangedSlot ()
 Receives signal about selection change, and pass it on with layer info.
void saveAsImage (QString theFileName, QPixmap *QPixmap=0, QString="PNG")
 Save the convtents of the map canvas to disk as an image.
void layerStateChange ()
 This slot is connected to the visibility change of one or more layers.
void setRenderFlag (bool theFlag)
 Whether to suppress rendering or not.
bool renderFlag ()
 State of render suppression flag.
bool hasCrsTransformEnabled ()
 A simple helper method to find out if on the fly projections are enabled or not.
void mapUnitsChanged ()
 The map units may have changed, so cope with that.
void updateMap ()
 updates pixmap on render progress
void showError (QgsMapLayer *mapLayer)
 show whatever error is exposed by the QgsMapLayer.
void readProject (const QDomDocument &)
 called to read map canvas settings from project
void writeProject (QDomDocument &)
 called to write map canvas settings to project

Signals

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 scaleChanged (double)
 Emitted when the scale of the map changes.
void extentsChanged ()
 Emitted when the extents of the map change.
void renderComplete (QPainter *)
 Emitted when the canvas has rendered.
void renderStarting ()
 Emitted when the canvas is about to be rendered.
void layersChanged ()
 Emitted when a new set of layers has been received.
void keyPressed (QKeyEvent *e)
 Emit key press event.
void keyReleased (QKeyEvent *e)
 Emit key release event.
void mapToolSet (QgsMapTool *tool)
 Emit map tool changed event.
void selectionChanged (QgsMapLayer *layer)
 Emitted when selection in any layer gets changed.
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.
void setLayerSet (QList< QgsMapCanvasLayer > &layers)
void setCurrentLayer (QgsMapLayer *layer)
void updateOverview ()
void enableOverviewMode (QgsMapOverviewCanvas *overview)
QgsMapCanvasMapmap ()
QgsMapRenderermapRenderer ()
QPixmap & canvasPixmap ()
 Accessor for the canvas pixmap.
double scale ()
 Get the last reported scale of the canvas.
void clear ()
 Clear the map canvas.
double mapUnitsPerPixel () const
 Returns the mapUnitsPerPixel (map units per pixel) for the canvas.
QgsRectangle extent () const
 Returns the current zoom exent of the map canvas.
QgsRectangle fullExtent () const
 Returns the combined exent for all layers on the map canvas.
void setExtent (QgsRectangle const &r)
 Set the extent of the map canvas.
void zoomToFullExtent ()
 Zoom to the full extent of all layers.
void zoomToPreviousExtent ()
 Zoom to the previous extent (view).
void zoomToNextExtent ()
 Zoom to the Next extent (view).
void clearExtentHistory ()
void zoomToSelected (QgsVectorLayer *layer=NULL)
 Zoom to the extent of the selected features of current (vector) layer.
void setMapTool (QgsMapTool *mapTool)
 Sets the map tool currently being used on the canvas.
void unsetMapTool (QgsMapTool *mapTool)
 Unset the current map tool or last non zoom tool.
QgsMapToolmapTool ()
 Returns the currently active tool.
virtual void setCanvasColor (const QColor &_newVal)
 Write property of QColor bgColor.
virtual QColor canvasColor () const
 Read property of QColor bgColor.
void updateScale ()
 Emits signal scalChanged to update scale in main window.
void updateFullExtent ()
 Updates the full extent.
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. Added in v1.5
void freeze (bool frz=true)
bool isFrozen ()
void setDirty (bool _dirty)
 Flag the canvas as dirty and needed a refresh.
bool isDirty () const
 Return the state of the canvas (dirty or not).
void setMapUnits (QGis::UnitType mapUnits)
 Set map units (needed by project properties dialog).
QGis::UnitType mapUnits () const
 Get the current canvas map units.
const QgsMapToPixelgetCoordinateTransform ()
 Get the current coordinate transform.
bool isDrawing ()
 true if canvas currently drawing
QgsMapLayercurrentLayer ()
 returns current layer (set by legend widget)
void setWheelAction (WheelAction action, double factor=2)
 set wheel action and zoom factor (should be greater than 1)
void zoomIn ()
 Zoom in with fixed factor.
void zoomOut ()
 Zoom out with fixed factor.
void zoomScale (double scale)
 Zoom to a specific scale.
void zoomByFactor (double scaleFactor)
 Zoom with the factor supplied. Factor > 1 zooms out, interval (0,1) zooms in.
void zoomWithCenter (int x, int y, bool zoomIn)
 Zooms in/out with a given center.
void enableAntiAliasing (bool theFlag)
 used to determine if anti-aliasing is enabled or not
void useImageToRender (bool theFlag)
 Select which Qt class to render with.
void panActionEnd (QPoint releasePoint)
 Ends pan action and redraws the canvas.
void panAction (QMouseEvent *event)
 Called when mouse is moving and pan is activated.
QPoint mouseLastXY ()
 returns last position of mouse cursor

Protected Member Functions

void keyPressEvent (QKeyEvent *e)
 Overridden key press event.
void keyReleaseEvent (QKeyEvent *e)
 Overridden key release event.
void mouseDoubleClickEvent (QMouseEvent *e)
 Overridden mouse double click event.
void mouseMoveEvent (QMouseEvent *e)
 Overridden mouse move event.
void mousePressEvent (QMouseEvent *e)
 Overridden mouse press event.
void mouseReleaseEvent (QMouseEvent *e)
 Overridden mouse release event.
void wheelEvent (QWheelEvent *e)
 Overridden mouse wheel event.
void resizeEvent (QResizeEvent *e)
 Overridden resize event.
void moveCanvasContents (bool reset=false)
 called when panning is in action, reset indicates end of panning
void updateCanvasItemPositions ()
 called on resize or changed extent to notify canvas items to change their rectangle

Protected Attributes

std::auto_ptr< CanvasPropertiesmCanvasProperties
 Handle pattern for implementation object.

Private Member Functions

 QgsMapCanvas (QgsMapCanvas const &)
 this class is non-copyable
void connectNotify (const char *signal)
 debugging member invoked when a connect() is made to this object

Private Attributes

QgsMapRenderermMapRenderer
 all map rendering is done in this class
QgsMapCanvasMapmMap
 owns pixmap with rendered map and controls rendering
QgsMapOverviewCanvasmMapOverview
 map overview widget - it's controlled by QgsMapCanvas
bool mDrawing
 Flag indicating a map refresh is in progress.
bool mFrozen
 Flag indicating if the map canvas is frozen.
bool mDirty
 Flag to track the state of the Map canvas.
bool mRenderFlag
 determines whether user has requested to suppress rendering
QList< QPair< int, int > > mResizeQueue
 Resize events that have been ignored because the canvas is busy with rendering may put their sizes into this list.
QgsMapLayermCurrentLayer
 current layer in legend
QGraphicsScene * mScene
 graphics scene manages canvas items
QgsMapToolmMapTool
 pointer to current map tool
QgsMapToolmLastNonZoomMapTool
 previous tool if current is for zooming/panning
QList< QgsRectanglemLastExtent
 recently used extent
int mLastExtentIndex
double mWheelZoomFactor
 Scale factor multiple for default zoom in/out.
WheelAction mWheelAction
 Mouse wheel action.

Classes

class  CanvasProperties


Detailed Description

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

Definition at line 95 of file qgsmapcanvas.h.


Member Enumeration Documentation

Enumerator:
WheelZoom 
WheelZoomAndRecenter 
WheelZoomToMouseCursor 
WheelNothing 

Definition at line 101 of file qgsmapcanvas.h.


Constructor & Destructor Documentation

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

QgsMapCanvas::~QgsMapCanvas (  ) 

Destructor.

Definition at line 127 of file qgsmapcanvas.cpp.

References QgsMapTool::deactivate(), mLastNonZoomMapTool, mMapRenderer, mMapTool, and mScene.

QgsMapCanvas::QgsMapCanvas ( QgsMapCanvas const &   )  [private]

this class is non-copyable

Note:
Otherwise std::auto_ptr would pass the object responsiblity on to the copy like a hot potato leaving the copyer in a weird state.


Member Function Documentation

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

void QgsMapCanvas::setCurrentLayer ( QgsMapLayer layer  ) 

Definition at line 190 of file qgsmapcanvas.cpp.

References mCurrentLayer.

void QgsMapCanvas::updateOverview (  ) 

Definition at line 344 of file qgsmapcanvas.cpp.

References mMapOverview, and QgsMapOverviewCanvas::refresh().

Referenced by setLayerSet(), and updateFullExtent().

void QgsMapCanvas::enableOverviewMode ( QgsMapOverviewCanvas overview  ) 

Definition at line 318 of file qgsmapcanvas.cpp.

References hasCrsTransformEnabled(), mMapOverview, and mMapRenderer.

QgsMapCanvasMap * QgsMapCanvas::map (  ) 

Definition at line 169 of file qgsmapcanvas.cpp.

References mMap.

QgsMapRenderer * QgsMapCanvas::mapRenderer (  ) 

QPixmap & QgsMapCanvas::canvasPixmap (  ) 

Accessor for the canvas pixmap.

Definition at line 1222 of file qgsmapcanvas.cpp.

References mMap, and QgsMapCanvasMap::pixmap().

double QgsMapCanvas::scale ( void   ) 

Get the last reported scale of the canvas.

Definition at line 195 of file qgsmapcanvas.cpp.

References mMapRenderer, and QgsMapRenderer::scale().

Referenced by QgsMapCanvasItem::setRenderContextVariables(), updateScale(), and zoomScale().

void QgsMapCanvas::clear (  ) 

Clear the map canvas.

Definition at line 543 of file qgsmapcanvas.cpp.

References setDirty().

Referenced by refresh().

double QgsMapCanvas::mapUnitsPerPixel (  )  const

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

Definition at line 1229 of file qgsmapcanvas.cpp.

References QgsMapRenderer::mapUnitsPerPixel(), and mMapRenderer.

Referenced by saveAsImage().

QgsRectangle QgsMapCanvas::extent (  )  const

QgsRectangle QgsMapCanvas::fullExtent (  )  const

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

Definition at line 463 of file qgsmapcanvas.cpp.

References QgsMapRenderer::fullExtent(), and mMapRenderer.

Referenced by setLayerSet(), updateFullExtent(), and zoomToFullExtent().

void QgsMapCanvas::setExtent ( QgsRectangle const &  r  ) 

void QgsMapCanvas::zoomToFullExtent (  ) 

Zoom to the full extent of all layers.

Definition at line 552 of file qgsmapcanvas.cpp.

References extent(), fullExtent(), QgsRectangle::isEmpty(), mDrawing, refresh(), QgsRectangle::scale(), and setExtent().

void QgsMapCanvas::zoomToPreviousExtent (  ) 

void QgsMapCanvas::zoomToNextExtent (  ) 

void QgsMapCanvas::clearExtentHistory (  ) 

void QgsMapCanvas::zoomToSelected ( QgsVectorLayer layer = NULL  ) 

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

Added in version 1.2: optionally specify different than current layer

Definition at line 651 of file qgsmapcanvas.cpp.

References QgsVectorLayer::boundingBoxOfSelected(), QgsRectangle::center(), QgsRectangle::expand(), extent(), QgsRectangle::isEmpty(), QgsMapRenderer::layerExtentToOutputExtent(), mCurrentLayer, mDrawing, mMapRenderer, refresh(), QgsRectangle::scale(), QgsVectorLayer::selectedFeatureCount(), and setExtent().

void QgsMapCanvas::setMapTool ( QgsMapTool mapTool  ) 

Sets the map tool currently being used on the canvas.

Definition at line 1114 of file qgsmapcanvas.cpp.

References QgsMapTool::activate(), QgsMapTool::deactivate(), QgsMapTool::isTransient(), mapToolSet(), mLastNonZoomMapTool, and mMapTool.

Referenced by mouseReleaseEvent().

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 1142 of file qgsmapcanvas.cpp.

References QgsMapTool::deactivate(), mapToolSet(), mLastNonZoomMapTool, and mMapTool.

Referenced by QgsMapTool::~QgsMapTool().

QgsMapTool * QgsMapCanvas::mapTool (  ) 

Returns the currently active tool.

Definition at line 1273 of file qgsmapcanvas.cpp.

References mMapTool.

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

Write property of QColor bgColor.

Definition at line 1159 of file qgsmapcanvas.cpp.

References mMap, mScene, and QgsMapCanvasMap::setBackgroundColor().

QColor QgsMapCanvas::canvasColor (  )  const [virtual]

Read property of QColor bgColor.

Definition at line 1177 of file qgsmapcanvas.cpp.

References mScene.

Referenced by QgsQuickPrint::setMapCanvas().

void QgsMapCanvas::updateScale (  ) 

Emits signal scalChanged to update scale in main window.

Definition at line 535 of file qgsmapcanvas.cpp.

References mMapRenderer, QgsMapRenderer::scale(), scale(), and scaleChanged().

Referenced by mapUnitsChanged(), resizeEvent(), setExtent(), zoomToNextExtent(), and zoomToPreviousExtent().

void QgsMapCanvas::updateFullExtent (  ) 

QgsMapLayer * QgsMapCanvas::layer ( int  index  ) 

return the map layer at position index in the layer stack

Definition at line 180 of file qgsmapcanvas.cpp.

References QgsMapLayerRegistry::instance(), layers(), QgsMapRenderer::layerSet(), QgsMapLayerRegistry::mapLayer(), and mMapRenderer.

Referenced by layers(), selectionChangedSlot(), and setLayerSet().

int QgsMapCanvas::layerCount (  )  const

return number of layers on the map

Definition at line 1182 of file qgsmapcanvas.cpp.

References QgsMapRenderer::layerSet(), and mMapRenderer.

Referenced by setLayerSet().

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

return list of layers within map canvas. Added in v1.5

Definition at line 1188 of file qgsmapcanvas.cpp.

References QgsMapLayerRegistry::instance(), layer(), QgsMapRenderer::layerSet(), QgsMapLayerRegistry::mapLayer(), and mMapRenderer.

Referenced by layer(), and QgsFormAnnotationItem::updateVisibility().

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

Definition at line 1211 of file qgsmapcanvas.cpp.

References mFrozen.

bool QgsMapCanvas::isFrozen (  ) 

Accessor for frozen status of canvas

Definition at line 1216 of file qgsmapcanvas.cpp.

References mFrozen.

void QgsMapCanvas::setDirty ( bool  _dirty  ) 

Flag the canvas as dirty and needed a refresh.

Definition at line 200 of file qgsmapcanvas.cpp.

References mDirty.

Referenced by clear().

bool QgsMapCanvas::isDirty (  )  const

Return the state of the canvas (dirty or not).

Definition at line 205 of file qgsmapcanvas.cpp.

References mDirty.

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

Set map units (needed by project properties dialog).

Definition at line 1235 of file qgsmapcanvas.cpp.

References mMapRenderer, QgsDebugMsg, and QgsMapRenderer::setMapUnits().

QGis::UnitType QgsMapCanvas::mapUnits (  )  const

Get the current canvas map units.

Definition at line 1242 of file qgsmapcanvas.cpp.

References QgsMapRenderer::mapUnits(), and mMapRenderer.

const QgsMapToPixel * QgsMapCanvas::getCoordinateTransform (  ) 

bool QgsMapCanvas::isDrawing (  ) 

true if canvas currently drawing

Definition at line 212 of file qgsmapcanvas.cpp.

References mDrawing.

QgsMapLayer * QgsMapCanvas::currentLayer (  ) 

returns current layer (set by legend widget)

Definition at line 354 of file qgsmapcanvas.cpp.

References mCurrentLayer.

Referenced by setLayerSet(), QgsMapCanvasSnapper::snapToBackgroundLayers(), and QgsMapCanvasSnapper::snapToCurrentLayer().

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

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

Definition at line 1047 of file qgsmapcanvas.cpp.

References mWheelAction, and mWheelZoomFactor.

Referenced by QgsMapCanvas().

void QgsMapCanvas::zoomIn (  ) 

Zoom in with fixed factor.

Definition at line 1053 of file qgsmapcanvas.cpp.

References mWheelZoomFactor, and zoomByFactor().

Referenced by keyPressEvent(), and wheelEvent().

void QgsMapCanvas::zoomOut (  ) 

Zoom out with fixed factor.

Definition at line 1058 of file qgsmapcanvas.cpp.

References mWheelZoomFactor, and zoomByFactor().

Referenced by keyPressEvent(), and wheelEvent().

void QgsMapCanvas::zoomScale ( double  scale  ) 

Zoom to a specific scale.

Definition at line 1063 of file qgsmapcanvas.cpp.

References scale(), and zoomByFactor().

void QgsMapCanvas::zoomByFactor ( double  scaleFactor  ) 

Zoom with the factor supplied. Factor > 1 zooms out, interval (0,1) zooms in.

Definition at line 1435 of file qgsmapcanvas.cpp.

References QgsMapRenderer::extent(), mDrawing, mMapRenderer, refresh(), QgsRectangle::scale(), and setExtent().

Referenced by zoomIn(), zoomOut(), and zoomScale().

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

void QgsMapCanvas::enableAntiAliasing ( bool  theFlag  ) 

used to determine if anti-aliasing is enabled or not

Definition at line 156 of file qgsmapcanvas.cpp.

References QgsMapOverviewCanvas::enableAntiAliasing(), QgsMapCanvasMap::enableAntiAliasing(), mMap, and mMapOverview.

void QgsMapCanvas::useImageToRender ( bool  theFlag  ) 

Select which Qt class to render with.

Definition at line 163 of file qgsmapcanvas.cpp.

References mMap, refresh(), and QgsMapCanvasMap::useImageToRender().

void QgsMapCanvas::panActionEnd ( QPoint  releasePoint  ) 

void QgsMapCanvas::panAction ( QMouseEvent *  event  ) 

Called when mouse is moving and pan is activated.

Definition at line 1326 of file qgsmapcanvas.cpp.

References mDrawing, and moveCanvasContents().

Referenced by QgsMapToolPan::canvasMoveEvent(), and mouseMoveEvent().

QPoint QgsMapCanvas::mouseLastXY (  ) 

returns last position of mouse cursor

Definition at line 1395 of file qgsmapcanvas.cpp.

References mCanvasProperties.

void QgsMapCanvas::refresh (  )  [slot]

void QgsMapCanvas::selectionChangedSlot (  )  [slot]

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

Definition at line 1448 of file qgsmapcanvas.cpp.

References layer(), refresh(), and selectionChanged().

Referenced by setLayerSet().

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

void QgsMapCanvas::layerStateChange (  )  [slot]

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

Definition at line 1201 of file qgsmapcanvas.cpp.

References refresh().

void QgsMapCanvas::setRenderFlag ( bool  theFlag  )  [slot]

Whether to suppress rendering or not.

Definition at line 1248 of file qgsmapcanvas.cpp.

References mMapRenderer, mRenderFlag, refresh(), QgsMapRenderer::rendererContext(), and QgsRenderContext::setRenderingStopped().

bool QgsMapCanvas::renderFlag (  )  [inline, slot]

State of render suppression flag.

Definition at line 275 of file qgsmapcanvas.h.

bool QgsMapCanvas::hasCrsTransformEnabled (  )  [slot]

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

Definition at line 628 of file qgsmapcanvas.cpp.

References QgsMapRenderer::hasCrsTransformEnabled(), and mMapRenderer.

Referenced by enableOverviewMode().

void QgsMapCanvas::mapUnitsChanged (  )  [slot]

The map units may have changed, so cope with that.

Definition at line 633 of file qgsmapcanvas.cpp.

References refresh(), and updateScale().

void QgsMapCanvas::updateMap (  )  [slot]

updates pixmap on render progress

Definition at line 398 of file qgsmapcanvas.cpp.

References mMap, and QgsMapCanvasMap::updateContents().

Referenced by setLayerSet().

void QgsMapCanvas::showError ( QgsMapLayer mapLayer  )  [slot]

show whatever error is exposed by the QgsMapLayer.

Definition at line 1375 of file qgsmapcanvas.cpp.

References QgsMapLayer::lastError(), QgsMapLayer::lastErrorTitle(), QgsMapLayer::name(), and QgsMessageViewer::setMessageAsPlainText().

Referenced by QgsMapCanvas().

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

called to read map canvas settings from project

Definition at line 1400 of file qgsmapcanvas.cpp.

References clearExtentHistory(), mMapRenderer, QgsDebugMsg, and QgsMapRenderer::readXML().

Referenced by QgsMapCanvas().

void QgsMapCanvas::writeProject ( QDomDocument &  doc  )  [slot]

called to write map canvas settings to project

Definition at line 1416 of file qgsmapcanvas.cpp.

References mMapRenderer, QgsDebugMsg, and QgsMapRenderer::writeXML().

Referenced by QgsMapCanvas().

void QgsMapCanvas::setProgress ( int  ,
int   
) [signal]

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

void QgsMapCanvas::xyCoordinates ( const QgsPoint p  )  [signal]

emits current mouse position

Note:
changed in 1.3

Referenced by mouseMoveEvent().

void QgsMapCanvas::scaleChanged ( double   )  [signal]

Emitted when the scale of the map changes.

Referenced by updateScale().

void QgsMapCanvas::extentsChanged (  )  [signal]

Emitted when the extents of the map change.

Referenced by resizeEvent(), setExtent(), zoomToNextExtent(), and zoomToPreviousExtent().

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.

Referenced by refresh(), and saveAsImage().

void QgsMapCanvas::renderStarting (  )  [signal]

Emitted when the canvas is about to be rendered.

Note:
Added in 1.5

Referenced by refresh().

void QgsMapCanvas::layersChanged (  )  [signal]

Emitted when a new set of layers has been received.

Referenced by setLayerSet().

void QgsMapCanvas::keyPressed ( QKeyEvent *  e  )  [signal]

Emit key press event.

Referenced by keyPressEvent().

void QgsMapCanvas::keyReleased ( QKeyEvent *  e  )  [signal]

Emit key release event.

Referenced by keyReleaseEvent().

void QgsMapCanvas::mapToolSet ( QgsMapTool tool  )  [signal]

Emit map tool changed event.

Referenced by setMapTool(), and unsetMapTool().

void QgsMapCanvas::selectionChanged ( QgsMapLayer layer  )  [signal]

Emitted when selection in any layer gets changed.

Referenced by selectionChangedSlot(), and setLayerSet().

void QgsMapCanvas::zoomLastStatusChanged ( bool   )  [signal]

Emitted when zoom last status changed.

Note:
: this signal was added in version 1.4

Referenced by clearExtentHistory(), setExtent(), zoomToNextExtent(), and zoomToPreviousExtent().

void QgsMapCanvas::zoomNextStatusChanged ( bool   )  [signal]

Emitted when zoom next status changed.

Note:
: this signal was added in version 1.4

Referenced by clearExtentHistory(), setExtent(), zoomToNextExtent(), and zoomToPreviousExtent().

void QgsMapCanvas::keyPressEvent ( QKeyEvent *  e  )  [protected]

void QgsMapCanvas::keyReleaseEvent ( QKeyEvent *  e  )  [protected]

Overridden key release event.

Definition at line 798 of file qgsmapcanvas.cpp.

References keyReleased(), QgsMapTool::keyReleaseEvent(), mCanvasProperties, mDrawing, mMapTool, panActionEnd(), and QgsDebugMsg.

void QgsMapCanvas::mouseDoubleClickEvent ( QMouseEvent *  e  )  [protected]

Overridden mouse double click event.

Definition at line 836 of file qgsmapcanvas.cpp.

References QgsMapTool::canvasDoubleClickEvent(), mDrawing, and mMapTool.

void QgsMapCanvas::mouseMoveEvent ( QMouseEvent *  e  )  [protected]

void QgsMapCanvas::mousePressEvent ( QMouseEvent *  e  )  [protected]

Overridden mouse press event.

Definition at line 849 of file qgsmapcanvas.cpp.

References QgsMapTool::canvasPressEvent(), mCanvasProperties, mDrawing, and mMapTool.

void QgsMapCanvas::mouseReleaseEvent ( QMouseEvent *  e  )  [protected]

void QgsMapCanvas::wheelEvent ( QWheelEvent *  e  )  [protected]

void QgsMapCanvas::resizeEvent ( QResizeEvent *  e  )  [protected]

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

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

Definition at line 1340 of file qgsmapcanvas.cpp.

References mCanvasProperties, mDrawing, mMap, mScene, QgsMapCanvasItem::setPanningOffset(), QgsMapCanvasMap::setPanningOffset(), and updateCanvasItemPositions().

Referenced by panAction(), panActionEnd(), and QgsMapCanvas().

void QgsMapCanvas::updateCanvasItemPositions (  )  [protected]

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

Definition at line 978 of file qgsmapcanvas.cpp.

References mScene, and QgsMapCanvasItem::updatePosition().

Referenced by moveCanvasContents(), resizeEvent(), and setExtent().

void QgsMapCanvas::connectNotify ( const char *  signal  )  [private]

debugging member invoked when a connect() is made to this object

Definition at line 1266 of file qgsmapcanvas.cpp.

References QgsDebugMsg.


Member Data Documentation

Handle pattern for implementation object.

Definition at line 378 of file qgsmapcanvas.h.

Referenced by keyPressEvent(), keyReleaseEvent(), mouseLastXY(), mouseMoveEvent(), mousePressEvent(), mouseReleaseEvent(), moveCanvasContents(), and panActionEnd().

owns pixmap with rendered map and controls rendering

Definition at line 397 of file qgsmapcanvas.h.

Referenced by canvasPixmap(), enableAntiAliasing(), map(), moveCanvasContents(), QgsMapCanvas(), refresh(), resizeEvent(), saveAsImage(), setCanvasColor(), updateMap(), and useImageToRender().

bool QgsMapCanvas::mDrawing [private]

bool QgsMapCanvas::mFrozen [private]

Flag indicating if the map canvas is frozen.

Definition at line 406 of file qgsmapcanvas.h.

Referenced by freeze(), isFrozen(), QgsMapCanvas(), and refresh().

bool QgsMapCanvas::mDirty [private]

Flag to track the state of the Map canvas.

The canvas is flagged as dirty by any operation that changes the state of the layers or the view extent. If the canvas is not dirty, paint events are handled by bit-blitting the stored canvas bitmap to the canvas. This improves performance by not reading the data source when no real change has occurred

Definition at line 417 of file qgsmapcanvas.h.

Referenced by isDirty(), QgsMapCanvas(), refresh(), and setDirty().

bool QgsMapCanvas::mRenderFlag [private]

determines whether user has requested to suppress rendering

Definition at line 420 of file qgsmapcanvas.h.

Referenced by QgsMapCanvas(), refresh(), and setRenderFlag().

QList< QPair<int, int> > QgsMapCanvas::mResizeQueue [private]

Resize events that have been ignored because the canvas is busy with rendering may put their sizes into this list.

The canvas then picks up the last entry in case a lot of resize events arrive in short time

Definition at line 425 of file qgsmapcanvas.h.

current layer in legend

Definition at line 433 of file qgsmapcanvas.h.

Referenced by currentLayer(), mouseReleaseEvent(), QgsMapCanvas(), setCurrentLayer(), and zoomToSelected().

QGraphicsScene* QgsMapCanvas::mScene [private]

graphics scene manages canvas items

Definition at line 436 of file qgsmapcanvas.h.

Referenced by canvasColor(), moveCanvasContents(), QgsMapCanvas(), resizeEvent(), setCanvasColor(), updateCanvasItemPositions(), and ~QgsMapCanvas().

previous tool if current is for zooming/panning

Definition at line 442 of file qgsmapcanvas.h.

Referenced by mouseReleaseEvent(), QgsMapCanvas(), setMapTool(), unsetMapTool(), and ~QgsMapCanvas().

recently used extent

Definition at line 445 of file qgsmapcanvas.h.

Referenced by clearExtentHistory(), setExtent(), zoomToNextExtent(), and zoomToPreviousExtent().

Scale factor multiple for default zoom in/out.

Definition at line 449 of file qgsmapcanvas.h.

Referenced by setWheelAction(), wheelEvent(), zoomIn(), zoomOut(), and zoomWithCenter().

Mouse wheel action.

Definition at line 452 of file qgsmapcanvas.h.

Referenced by setWheelAction(), and wheelEvent().


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

Generated on Sat Feb 4 19:17:37 2012 for Quantum GIS API Documentation by  doxygen 1.5.6