| QGIS API Documentation
    3.20.0-Odense (decaadbb31)
    | 
A widget for showing the bounds of a rectangular region on an interactive map. More...
#include <qgscoordinateboundspreviewmapwidget.h>

| Public Member Functions | |
| QgsCoordinateBoundsPreviewMapWidget (QWidget *parent=nullptr) | |
| Constructor for QgsCoordinateBoundsPreviewMapWidget.  More... | |
| ~QgsCoordinateBoundsPreviewMapWidget () override | |
| QgsRectangle | canvasRect () const | 
| Returns the current canvas bounds rectangle shown in the map.  More... | |
| void | setCanvasRect (const QgsRectangle &rect) | 
| Sets the canvas bounds rectangle for the bounds overview map.  More... | |
| void | setPreviewRect (const QgsRectangle &rect) | 
| Sets the "preview" rectangle for the bounds overview map.  More... | |
|  Public Member Functions inherited from QgsMapCanvas | |
| QgsMapCanvas (QWidget *parent=nullptr) | |
| Constructor.  More... | |
| ~QgsMapCanvas () override | |
| bool | allowInteraction (QgsMapCanvasInteractionBlocker::Interaction interaction) const | 
| Returns trueif the specified interaction is currently permitted on the canvas.  More... | |
| QList< QgsMapCanvasAnnotationItem * > | annotationItems () const | 
| Returns a list of all annotation items in the canvas.  More... | |
| bool | annotationsVisible () const | 
| Returns trueif annotations are visible within the map canvas.  More... | |
| bool | antiAliasingEnabled () const | 
| trueif antialiasing 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 () | 
| Clears the list of extents and sets current extent as first item.  More... | |
| QgsExpressionContext | createExpressionContext () const override | 
| This method needs to be reimplemented in all classes which implement this interface and return an expression context.  More... | |
| QgsMapLayer * | currentLayer () | 
| returns current layer (set by legend widget)  More... | |
| QgsExpressionContextScope * | defaultExpressionContextScope () const | 
| 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... | |
| void | installInteractionBlocker (QgsMapCanvasInteractionBlocker *blocker) | 
| Installs an interaction blocker onto the canvas, which may prevent certain map canvas interactions from occurring.  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 trueif 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 (bool allowOutdatedResults=true) 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 | panActionStart (QPoint releasePoint) | 
| Starts a pan action.  More... | |
| void | panToFeatureIds (QgsVectorLayer *layer, const QgsFeatureIds &ids, bool alwaysRecenter=true) | 
| Centers canvas extent to feature ids.  More... | |
| void | panToSelected (const QList< QgsMapLayer * > &layers) | 
| Pan to the combined extent of the selected features of all provided (vector) layers.  More... | |
| void | panToSelected (QgsVectorLayer *layer=nullptr) | 
| Pan to the selected features of current (vector) layer keeping same extent.  More... | |
| bool | previewJobsEnabled () const | 
| Returns trueif 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... | |
| QgsProject * | project () | 
| Returns the project linked to this canvas.  More... | |
| QgsRectangle | projectExtent () const | 
| Returns the associated project's full extent, in the canvas' CRS.  More... | |
| void | removeInteractionBlocker (QgsMapCanvasInteractionBlocker *blocker) | 
| Removes an interaction blocker from the canvas.  More... | |
| bool | renderFlag () const | 
| Returns trueif 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 ¢er) | 
| 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 to the specified rectangle.  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... | |
| void | setProject (QgsProject *project) | 
| Sets the project linked to this 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 | setTemporalController (QgsTemporalController *controller) | 
| Sets the temporal controller for this canvas.  More... | |
| void | setTemporalRange (const QgsDateTimeRange &range) | 
| Set datetime range for 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... | |
| const QgsTemporalController * | temporalController () const | 
| Gets access to the temporal controller that will be used to update the canvas temporal range.  More... | |
| const QgsDateTimeRange & | temporalRange () const | 
| Returns map canvas datetime range.  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, bool ignoreScaleLock=false) | 
| Zoom with the factor supplied.  More... | |
| void | zoomScale (double scale, bool ignoreScaleLock=false) | 
| 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 currently visible in the canvas.  More... | |
| void | zoomToNextExtent () | 
| Zoom to the next extent (view)  More... | |
| void | zoomToPreviousExtent () | 
| Zoom to the previous extent (view)  More... | |
| void | zoomToProjectExtent () | 
| Zoom to the full extent the project associated with this canvas.  More... | |
| void | zoomWithCenter (int x, int y, bool zoomIn) | 
| Zooms in/out with a given center.  More... | |
|  Public Member Functions inherited from QgsExpressionContextGenerator | |
| virtual | ~QgsExpressionContextGenerator ()=default | 
| Additional Inherited Members | |
|  Public Slots inherited from QgsMapCanvas | |
| 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, const QgsPointXY *center=nullptr) | 
| 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 | setZoomResolutions (const QList< double > &resolutions) | 
| Set a list of resolutions (map units per pixel) to which to "snap to" when zooming the map.  More... | |
| void | setZRange (const QgsDoubleRange &range) | 
| Sets the range of z-values which will be visible in the map.  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... | |
| double | zoomInFactor () const | 
| Returns the zoom in factor.  More... | |
| void | zoomOut () | 
| Zoom out with fixed factor.  More... | |
| double | zoomOutFactor () const | 
| Returns the zoom in factor.  More... | |
| const QList< double > & | zoomResolutions () const | 
| void | zoomToSelected (const QList< QgsMapLayer * > &layers) | 
| Zoom to the combined extent of the selected features of all provided (vector) layers.  More... | |
| void | zoomToSelected (QgsVectorLayer *layer=nullptr) | 
| Zoom to the extent of the selected features of provided (vector) layer.  More... | |
| QgsDoubleRange | zRange () const | 
| Returns the range of z-values which will be visible in the map.  More... | |
|  Signals inherited from QgsMapCanvas | |
| void | canvasColorChanged () | 
| Emitted when canvas background color changes.  More... | |
| void | contextMenuAboutToShow (QMenu *menu, QgsMapMouseEvent *event) | 
| Emitted before the map canvas context menu will be shown.  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 | mapRefreshCanceled () | 
| Emitted when the pending map refresh has been canceled.  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::MessageLevel::Info) | 
| emit a message (usually to be displayed in a message bar)  More... | |
| void | panDistanceBearingChanged (double distance, QgsUnitTypes::DistanceUnit unit, double bearing) | 
| Emitted whenever the distance or bearing of an in-progress panning operation is changed.  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 | scaleLockChanged (bool locked) | 
| Emitted when the scale locked state of the map changes.  More... | |
| void | selectionChanged (QgsVectorLayer *layer) | 
| Emitted when selection in any layer gets changed.  More... | |
| void | tapAndHoldGestureOccurred (const QgsPointXY &mapPoint, QTapAndHoldGesture *gesture) | 
| Emitted whenever a tap and hold gesture occurs at the specified map point.  More... | |
| void | temporalRangeChanged () | 
| Emitted when the map canvas temporal range changes.  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... | |
| void | zRangeChanged () | 
| Emitted when the map canvas z (elevation) range changes.  More... | |
|  Protected Slots inherited from QgsMapCanvas | |
| void | updateCanvasItemPositions () | 
| called on resize or changed extent to notify canvas items to change their rectangle  More... | |
|  Protected Member Functions inherited from QgsMapCanvas | |
| 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 inherited from QgsMapCanvas | |
| std::unique_ptr< CanvasProperties > | mCanvasProperties | 
| Handle pattern for implementation object.  More... | |
|  Properties inherited from QgsMapCanvas | |
| bool | previewJobsEnabled | 
| QString | theme | 
A widget for showing the bounds of a rectangular region on an interactive map.
Definition at line 27 of file qgscoordinateboundspreviewmapwidget.h.
| QgsCoordinateBoundsPreviewMapWidget::QgsCoordinateBoundsPreviewMapWidget | ( | QWidget * | parent = nullptr | ) | 
Constructor for QgsCoordinateBoundsPreviewMapWidget.
Definition at line 18 of file qgscoordinateboundspreviewmapwidget.cpp.
| 
 | override | 
Definition at line 44 of file qgscoordinateboundspreviewmapwidget.cpp.
| QgsRectangle QgsCoordinateBoundsPreviewMapWidget::canvasRect | ( | ) | const | 
Returns the current canvas bounds rectangle shown in the map.
Definition at line 83 of file qgscoordinateboundspreviewmapwidget.cpp.
| void QgsCoordinateBoundsPreviewMapWidget::setCanvasRect | ( | const QgsRectangle & | rect | ) | 
Sets the canvas bounds rectangle for the bounds overview map.
Must be in EPSG:4326 coordinate reference system.
Definition at line 88 of file qgscoordinateboundspreviewmapwidget.cpp.
| void QgsCoordinateBoundsPreviewMapWidget::setPreviewRect | ( | const QgsRectangle & | rect | ) | 
Sets the "preview" rectangle for the bounds overview map.
Must be in EPSG:4326 coordinate reference system.
Definition at line 52 of file qgscoordinateboundspreviewmapwidget.cpp.