Map tool for identifying features in layers. More...

#include <qgsmaptoolidentify.h>

Inheritance diagram for QgsMapToolIdentify:

[legend]

Classes
struct	IdentifyResult

Public Types
enum	IdentifyMode { DefaultQgsSetting = -1 , ActiveLayer , TopDownStopAtFirst , TopDownAll , LayerSelection }

typedef QFlags< Type >	LayerType

enum	Type { VectorLayer = 1 , RasterLayer = 2 , MeshLayer = 4 , VectorTileLayer = 8 , PointCloudLayer = 16 , AllLayers = VectorLayer \| RasterLayer \| MeshLayer \| VectorTileLayer \| PointCloudLayer }

Public Types inherited from QgsMapTool
enum	Flag { Transient = 1 << 1 , EditTool = 1 << 2 , AllowZoomRect = 1 << 3 , ShowContextMenu = 1 << 4 }
	Enumeration of flags that adjust the way the map tool operates. More...

typedef QFlags< Flag >	Flags

Public Slots
void	formatChanged (QgsRasterLayer *layer)

Signals
void	changedRasterResults (QList< QgsMapToolIdentify::IdentifyResult > &results)
	Emitted when the format of raster results is changed and need to be updated in user-facing displays.

void	identifyMessage (const QString &message)
	Emitted when the identify operation needs to show a user-facing message.

void	identifyProgress (int processed, int total)
	Emitted when the identify action progresses.

Signals inherited from QgsMapTool
void	activated ()
	signal emitted once the map tool is activated

void	deactivated ()
	signal emitted once the map tool is deactivated

void	messageDiscarded ()
	emit signal to clear previous message

void	messageEmitted (const QString &message, Qgis::MessageLevel=Qgis::MessageLevel::Info)
	emit a message

void	reactivated ()

Public Member Functions
	QgsMapToolIdentify (QgsMapCanvas *canvas)
	constructor

	~QgsMapToolIdentify () override

void	activate () override
	called when set as currently active map tool

void	canvasMoveEvent (QgsMapMouseEvent *e) override
	Mouse move event for overriding. Default implementation does nothing.

void	canvasPressEvent (QgsMapMouseEvent *e) override
	Mouse press event for overriding. Default implementation does nothing.

void	canvasReleaseEvent (QgsMapMouseEvent *e) override
	Mouse release event for overriding. Default implementation does nothing.

void	deactivate () override
	called when map tool is being deactivated

Flags	flags () const override
	Returns the flags for the map tool.

void	fromElevationProfileLayerIdentificationToIdentifyResults (QgsMapLayer *layer, const QVector< QVariantMap > &identified, QList< QgsMapToolIdentify::IdentifyResult > &results)
	Converts elevation profile identification results from variant maps to QgsMapToolIdentify::IdentifyResult and apply some formatting.

QList< QgsMapToolIdentify::IdentifyResult >	identify (const QgsGeometry &geometry, IdentifyMode mode, const QList< QgsMapLayer * > &layerList, LayerType layerType, const QgsIdentifyContext &identifyContext=QgsIdentifyContext())
	Performs identification based on a geometry (in map coordinates)

QList< QgsMapToolIdentify::IdentifyResult >	identify (const QgsGeometry &geometry, IdentifyMode mode, LayerType layerType, const QgsIdentifyContext &identifyContext=QgsIdentifyContext())
	Performs identification based on a geometry (in map coordinates)

QList< QgsMapToolIdentify::IdentifyResult >	identify (int x, int y, const QList< QgsMapLayer * > &layerList=QList< QgsMapLayer * >(), IdentifyMode mode=DefaultQgsSetting, const QgsIdentifyContext &identifyContext=QgsIdentifyContext())
	Performs the identification.

QList< QgsMapToolIdentify::IdentifyResult >	identify (int x, int y, IdentifyMode mode, LayerType layerType=AllLayers, const QgsIdentifyContext &identifyContext=QgsIdentifyContext())
	Performs the identification.

QgsIdentifyMenu *	identifyMenu ()
	Returns a pointer to the identify menu which will be used in layer selection mode this menu can also be customized.

Public Member Functions inherited from QgsMapTool
	~QgsMapTool () override

QAction *	action ()
	Returns associated action with map tool or `nullptr` if no action is associated.

QAbstractButton *	button ()
	Returns associated button with map tool or `nullptr` if no button is associated.

QgsMapCanvas *	canvas () const
	returns pointer to the tool's map canvas

virtual void	canvasDoubleClickEvent (QgsMapMouseEvent *e)
	Mouse double-click event for overriding. Default implementation does nothing.

virtual bool	canvasToolTipEvent (QHelpEvent *e)
	Tooltip event for overriding.

virtual void	clean ()
	convenient method to clean members

virtual bool	gestureEvent (QGestureEvent *e)
	gesture event for overriding. Default implementation does nothing.

bool	isActive () const
	Returns if the current map tool active on the map canvas.

virtual void	keyPressEvent (QKeyEvent *e)
	Key event for overriding. Default implementation does nothing.

virtual void	keyReleaseEvent (QKeyEvent *e)
	Key event for overriding. Default implementation does nothing.

virtual void	populateContextMenu (QMenu *menu)
	Allows the tool to populate and customize the given menu, prior to showing it in response to a right-mouse button click.

virtual bool	populateContextMenuWithEvent (QMenu menu, QgsMapMouseEvent event)
	Allows the tool to populate and customize the given menu, prior to showing it in response to a right-mouse button click.

virtual void	reactivate ()
	Called when the map tool is being activated while it is already active.

void	setAction (QAction *action)
	Use this to associate a QAction to this maptool.

void	setButton (QAbstractButton *button)
	Use this to associate a button to this maptool.

virtual void	setCursor (const QCursor &cursor)
	Sets a user defined cursor.

QgsPointXY	toMapCoordinates (QPoint point)
	Transforms a point from screen coordinates to map coordinates.

QString	toolName ()
	Emit map tool changed with the old tool.

virtual void	wheelEvent (QWheelEvent *e)
	Mouse wheel event for overriding. Default implementation does nothing.

Static Public Member Functions
static void	fromPointCloudIdentificationToIdentifyResults (QgsPointCloudLayer *layer, const QVector< QVariantMap > &identified, QList< QgsMapToolIdentify::IdentifyResult > &results)
	Converts point cloud identification results from variant maps to QgsMapToolIdentify::IdentifyResult and apply some formatting.

Static Public Member Functions inherited from QgsMapTool
static double	searchRadiusMM ()
	Gets search radius in mm.

static double	searchRadiusMU (const QgsRenderContext &context)
	Gets search radius in map units for given context.

static double	searchRadiusMU (QgsMapCanvas *canvas)
	Gets search radius in map units for given canvas.

Protected Member Functions
QMap< QString, QString >	derivedAttributesForPoint (const QgsPoint &point)
	Returns derived attributes map for a clicked point in map coordinates. May be 2D or 3D point.

QList< QgsMapToolIdentify::IdentifyResult >	identify (int x, int y, IdentifyMode mode, const QList< QgsMapLayer * > &layerList, LayerType layerType=AllLayers, const QgsIdentifyContext &identifyContext=QgsIdentifyContext())
	Performs the identification.

bool	identifyLayer (QList< QgsMapToolIdentify::IdentifyResult > results, QgsMapLayer layer, const QgsPointXY &point, const QgsRectangle &viewExtent, double mapUnitsPerPixel, QgsMapToolIdentify::LayerType layerType=AllLayers, const QgsIdentifyContext &identifyContext=QgsIdentifyContext())
	Call the right method depending on layer type.

bool	identifyMeshLayer (QList< QgsMapToolIdentify::IdentifyResult > results, QgsMeshLayer layer, const QgsPointXY &point, const QgsIdentifyContext &identifyContext=QgsIdentifyContext())
	Identifies data from active scalar and vector dataset from the mesh layer.

bool	identifyRasterLayer (QList< QgsMapToolIdentify::IdentifyResult > results, QgsRasterLayer layer, QgsPointXY point, const QgsRectangle &viewExtent, double mapUnitsPerPixel, const QgsIdentifyContext &identifyContext=QgsIdentifyContext())
	Performs the identification against a given raster layer.

bool	identifyVectorLayer (QList< QgsMapToolIdentify::IdentifyResult > results, QgsVectorLayer layer, const QgsPointXY &point, const QgsIdentifyContext &identifyContext=QgsIdentifyContext())
	Performs the identification against a given vector layer.

void	restoreCanvasPropertiesOverrides ()
	Clears canvas properties overrides previously set with setCanvasPropertiesOverrides()

void	setCanvasPropertiesOverrides (double searchRadiusMapUnits)
	Overrides some map canvas properties inside the map tool for the upcoming identify requests.

Protected Member Functions inherited from QgsMapTool
	QgsMapTool (QgsMapCanvas *canvas)
	Constructor takes a map canvas as a parameter.

QgsMapLayer *	layer (const QString &id)
	Returns the map layer with the matching ID, or `nullptr` if no layers could be found.

void	setToolName (const QString &name)
	Sets the tool's name.

QPoint	toCanvasCoordinates (const QgsPointXY &point) const
	Transforms a point from map coordinates to screen coordinates.

QgsPoint	toLayerCoordinates (const QgsMapLayer *layer, const QgsPoint &point)
	Transforms a point from map coordinates to layer coordinates.

QgsPointXY	toLayerCoordinates (const QgsMapLayer *layer, const QgsPointXY &point)
	Transforms a point from map coordinates to layer coordinates.

QgsRectangle	toLayerCoordinates (const QgsMapLayer *layer, const QgsRectangle &rect)
	Transforms a rect from map coordinates to layer coordinates.

QgsPointXY	toLayerCoordinates (const QgsMapLayer *layer, QPoint point)
	Transforms a point from screen coordinates to layer coordinates.

QgsPoint	toMapCoordinates (const QgsMapLayer *layer, const QgsPoint &point)
	Transforms a point from layer coordinates to map coordinates (which is different in case reprojection is used).

QgsPointXY	toMapCoordinates (const QgsMapLayer *layer, const QgsPointXY &point)
	Transforms a point from layer coordinates to map coordinates (which is different in case reprojection is used).

Protected Attributes
QgsIdentifyMenu *	mIdentifyMenu = nullptr

Protected Attributes inherited from QgsMapTool
QAction *	mAction = nullptr
	Optional pointer to an action that will be checked on map tool activation and unchecked on map tool deactivation.

QAbstractButton *	mButton = nullptr
	Optional pointer to a button that will be checked on map tool activation and unchecked on map tool deactivation.

QPointer< QgsMapCanvas >	mCanvas
	The pointer to the map canvas.

QCursor	mCursor
	The cursor used in the map tool.

QString	mToolName
	The translated name of the map tool.

Detailed Description

Map tool for identifying features in layers.

after selecting a point, performs the identification:

for raster layers shows value of underlying pixel
for vector layers shows feature attributes within search radius (allows editing values when vector layer is in editing mode)

Definition at line 53 of file qgsmaptoolidentify.h.

Member Typedef Documentation

◆ LayerType

typedef QFlags< Type > QgsMapToolIdentify::LayerType

Definition at line 78 of file qgsmaptoolidentify.h.

Member Enumeration Documentation

◆ IdentifyMode

enum QgsMapToolIdentify::IdentifyMode

Enumerator
DefaultQgsSetting
ActiveLayer
TopDownStopAtFirst
TopDownAll
LayerSelection

Definition at line 59 of file qgsmaptoolidentify.h.

◆ Type

enum QgsMapToolIdentify::Type

Enumerator
VectorLayer
RasterLayer
MeshLayer	Since QGIS 3.6
VectorTileLayer	Since QGIS 3.14
PointCloudLayer	Since QGIS 3.18
AllLayers

Definition at line 69 of file qgsmaptoolidentify.h.

Constructor & Destructor Documentation

◆ QgsMapToolIdentify()

QgsMapToolIdentify::QgsMapToolIdentify ( QgsMapCanvas * canvas )

constructor

Definition at line 65 of file qgsmaptoolidentify.cpp.

◆ ~QgsMapToolIdentify()

QgsMapToolIdentify::~QgsMapToolIdentify ( )

override

Definition at line 74 of file qgsmaptoolidentify.cpp.

Member Function Documentation

◆ activate()

void QgsMapToolIdentify::activate ( )

overridevirtual

called when set as currently active map tool

Reimplemented from QgsMapTool.

Definition at line 201 of file qgsmaptoolidentify.cpp.

◆ canvasMoveEvent()

void QgsMapToolIdentify::canvasMoveEvent ( QgsMapMouseEvent * e )

overridevirtual

Mouse move event for overriding. Default implementation does nothing.

Reimplemented from QgsMapTool.

Definition at line 79 of file qgsmaptoolidentify.cpp.

◆ canvasPressEvent()

void QgsMapToolIdentify::canvasPressEvent ( QgsMapMouseEvent * e )

overridevirtual

Mouse press event for overriding. Default implementation does nothing.

Reimplemented from QgsMapTool.

Definition at line 84 of file qgsmaptoolidentify.cpp.

◆ canvasReleaseEvent()

void QgsMapToolIdentify::canvasReleaseEvent ( QgsMapMouseEvent * e )

overridevirtual

Mouse release event for overriding. Default implementation does nothing.

Reimplemented from QgsMapTool.

Reimplemented in QgsMapToolIdentifyFeature.

Definition at line 89 of file qgsmaptoolidentify.cpp.

◆ changedRasterResults

void QgsMapToolIdentify::changedRasterResults ( QList< QgsMapToolIdentify::IdentifyResult > & results )

signal

Emitted when the format of raster results is changed and need to be updated in user-facing displays.

◆ deactivate()

void QgsMapToolIdentify::deactivate ( )

overridevirtual

called when map tool is being deactivated

Reimplemented from QgsMapTool.

Definition at line 206 of file qgsmaptoolidentify.cpp.

◆ derivedAttributesForPoint()

QMap< QString, QString > QgsMapToolIdentify::derivedAttributesForPoint ( const QgsPoint & point )

protected

Returns derived attributes map for a clicked point in map coordinates. May be 2D or 3D point.

Definition at line 564 of file qgsmaptoolidentify.cpp.

◆ flags()

Flags QgsMapToolIdentify::flags ( ) const

inlineoverridevirtual

Returns the flags for the map tool.

Reimplemented from QgsMapTool.

Definition at line 109 of file qgsmaptoolidentify.h.

◆ formatChanged

void QgsMapToolIdentify::formatChanged ( QgsRasterLayer * layer )

slot

Definition at line 1477 of file qgsmaptoolidentify.cpp.

◆ fromElevationProfileLayerIdentificationToIdentifyResults()

void QgsMapToolIdentify::fromElevationProfileLayerIdentificationToIdentifyResults	(	QgsMapLayer *	layer,
		const QVector< QVariantMap > &	identified,
		QList< QgsMapToolIdentify::IdentifyResult > &	results
	)

Converts elevation profile identification results from variant maps to QgsMapToolIdentify::IdentifyResult and apply some formatting.

Note: Not available in Python bindings; The converted variant maps are pushed at the back of results without cleaning what's in it previously

Since: QGIS 3.26

Definition at line 1566 of file qgsmaptoolidentify.cpp.

◆ fromPointCloudIdentificationToIdentifyResults()

void QgsMapToolIdentify::fromPointCloudIdentificationToIdentifyResults	(	QgsPointCloudLayer *	layer,
		const QVector< QVariantMap > &	identified,
		QList< QgsMapToolIdentify::IdentifyResult > &	results
	)

static

Converts point cloud identification results from variant maps to QgsMapToolIdentify::IdentifyResult and apply some formatting.

Note: : the converted variant maps are pushed at the back of results without cleaning what's in it previously

Since: QGIS 3.18

Definition at line 1486 of file qgsmaptoolidentify.cpp.

◆ identify() [1/5]

QList< QgsMapToolIdentify::IdentifyResult > QgsMapToolIdentify::identify	(	const QgsGeometry &	geometry,
		IdentifyMode	mode,
		const QList< QgsMapLayer * > &	layerList,
		LayerType	layerType,
		const QgsIdentifyContext &	identifyContext = `QgsIdentifyContext()`
	)

Performs identification based on a geometry (in map coordinates)

Definition at line 114 of file qgsmaptoolidentify.cpp.

◆ identify() [2/5]

QList< QgsMapToolIdentify::IdentifyResult > QgsMapToolIdentify::identify	(	const QgsGeometry &	geometry,
		IdentifyMode	mode,
		LayerType	layerType,
		const QgsIdentifyContext &	identifyContext = `QgsIdentifyContext()`
	)

Performs identification based on a geometry (in map coordinates)

Definition at line 109 of file qgsmaptoolidentify.cpp.

◆ identify() [3/5]

QList< QgsMapToolIdentify::IdentifyResult > QgsMapToolIdentify::identify	(	int	x,
		int	y,
		const QList< QgsMapLayer * > &	layerList = `QList<QgsMapLayer *>()`,
		IdentifyMode	mode = `DefaultQgsSetting`,
		const QgsIdentifyContext &	identifyContext = `QgsIdentifyContext()`
	)

Performs the identification.

Parameters

x	x coordinates of mouseEvent
y	y coordinates of mouseEvent
layerList	Performs the identification within the given list of layers. Default value is an empty list, i.e. uses all the layers.
mode	Identification mode. Can use QGIS default settings or a defined mode. Default mode is DefaultQgsSetting.
identifyContext	Identify context object.

Returns: a list of IdentifyResult

Definition at line 94 of file qgsmaptoolidentify.cpp.

◆ identify() [4/5]

QList< QgsMapToolIdentify::IdentifyResult > QgsMapToolIdentify::identify	(	int	x,
		int	y,
		IdentifyMode	mode,
		const QList< QgsMapLayer * > &	layerList,
		LayerType	layerType = `AllLayers`,
		const QgsIdentifyContext &	identifyContext = `QgsIdentifyContext()`
	)

protected

Performs the identification.

To avoid being forced to specify IdentifyMode with a list of layers this has been made private and two publics methods are offered

Parameters

x	x coordinates of mouseEvent
y	y coordinates of mouseEvent
mode	Identification mode. Can use QGIS default settings or a defined mode.
layerList	Performs the identification within the given list of layers.
layerType	Only performs identification in a certain type of layers (raster, vector, mesh).
identifyContext	Identify context object.

Returns: a list of IdentifyResult

Definition at line 104 of file qgsmaptoolidentify.cpp.

◆ identify() [5/5]

QList< QgsMapToolIdentify::IdentifyResult > QgsMapToolIdentify::identify	(	int	x,
		int	y,
		IdentifyMode	mode,
		LayerType	layerType = `AllLayers`,
		const QgsIdentifyContext &	identifyContext = `QgsIdentifyContext()`
	)

Performs the identification.

To avoid being forced to specify IdentifyMode with a list of layers this has been made private and two publics methods are offered

Parameters

x	x coordinates of mouseEvent
y	y coordinates of mouseEvent
mode	Identification mode. Can use QGIS default settings or a defined mode.
layerType	Only performs identification in a certain type of layers (raster, vector, mesh). Default value is AllLayers.
identifyContext	Identify context object.

Returns: a list of IdentifyResult

Definition at line 99 of file qgsmaptoolidentify.cpp.

◆ identifyLayer()

bool QgsMapToolIdentify::identifyLayer	(	QList< QgsMapToolIdentify::IdentifyResult > *	results,
		QgsMapLayer *	layer,
		const QgsPointXY &	point,
		const QgsRectangle &	viewExtent,
		double	mapUnitsPerPixel,
		QgsMapToolIdentify::LayerType	layerType = `AllLayers`,
		const QgsIdentifyContext &	identifyContext = `QgsIdentifyContext()`
	)

protected

Call the right method depending on layer type.

Definition at line 211 of file qgsmaptoolidentify.cpp.

◆ identifyMenu()

QgsIdentifyMenu * QgsMapToolIdentify::identifyMenu ( )

inline

Returns a pointer to the identify menu which will be used in layer selection mode this menu can also be customized.

Definition at line 150 of file qgsmaptoolidentify.h.

◆ identifyMeshLayer()

bool QgsMapToolIdentify::identifyMeshLayer	(	QList< QgsMapToolIdentify::IdentifyResult > *	results,
		QgsMeshLayer *	layer,
		const QgsPointXY &	point,
		const QgsIdentifyContext &	identifyContext = `QgsIdentifyContext()`
	)

protected

Identifies data from active scalar and vector dataset from the mesh layer.

Works only if layer was already rendered (triangular mesh is created)

Since: QGIS 3.6

Definition at line 276 of file qgsmaptoolidentify.cpp.

◆ identifyMessage

void QgsMapToolIdentify::identifyMessage ( const QString & message )

signal

Emitted when the identify operation needs to show a user-facing message.

Parameters

message Message to show to the user

◆ identifyProgress

void QgsMapToolIdentify::identifyProgress	(	int	processed,
		int	total
	)

signal

Emitted when the identify action progresses.

Parameters

processed	number of objects processed so far
total	total number of objects to process

◆ identifyRasterLayer()

bool QgsMapToolIdentify::identifyRasterLayer	(	QList< QgsMapToolIdentify::IdentifyResult > *	results,
		QgsRasterLayer *	layer,
		QgsPointXY	point,
		const QgsRectangle &	viewExtent,
		double	mapUnitsPerPixel,
		const QgsIdentifyContext &	identifyContext = `QgsIdentifyContext()`
	)

protected

Performs the identification against a given raster layer.

Parameters

results	list of identify results
layer	raster layer to identify from
point	point coordinate to identify
viewExtent	view extent
mapUnitsPerPixel	map units per pixel value
identifyContext	identify context object

Definition at line 1099 of file qgsmaptoolidentify.cpp.

◆ identifyVectorLayer()

bool QgsMapToolIdentify::identifyVectorLayer	(	QList< QgsMapToolIdentify::IdentifyResult > *	results,
		QgsVectorLayer *	layer,
		const QgsPointXY &	point,
		const QgsIdentifyContext &	identifyContext = `QgsIdentifyContext()`
	)

protected

Performs the identification against a given vector layer.

Parameters

results	list of identify results
layer	raster layer to identify from
point	point coordinate to identify
identifyContext	identify context object

Definition at line 265 of file qgsmaptoolidentify.cpp.

◆ restoreCanvasPropertiesOverrides()

void QgsMapToolIdentify::restoreCanvasPropertiesOverrides ( )

protected

Clears canvas properties overrides previously set with setCanvasPropertiesOverrides()

See also: setCanvasPropertiesOverrides()

Since: QGIS 3.4

Definition at line 196 of file qgsmaptoolidentify.cpp.

◆ setCanvasPropertiesOverrides()

void QgsMapToolIdentify::setCanvasPropertiesOverrides ( double searchRadiusMapUnits )

protected

Overrides some map canvas properties inside the map tool for the upcoming identify requests.

This is useful when the identification is triggered by some other piece of GUI like a 3D map view and some properties like search radius need to be adjusted so that identification returns correct results. Currently only search radius may be overridden.

When the custom identification has finished, restoreCanvasPropertiesOverrides() should be called to erase any overrides.

See also: restoreCanvasPropertiesOverrides()

Since: QGIS 3.4

Definition at line 191 of file qgsmaptoolidentify.cpp.

Member Data Documentation

◆ mIdentifyMenu

QgsIdentifyMenu* QgsMapToolIdentify::mIdentifyMenu = nullptr

protected

Definition at line 208 of file qgsmaptoolidentify.h.

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

/build/qgis-3.40.0+99sid/src/gui/maptools/qgsmaptoolidentify.h
/build/qgis-3.40.0+99sid/src/gui/maptools/qgsmaptoolidentify.cpp

Classes

Public Types

Public Slots

Signals

Public Member Functions

Static Public Member Functions

Protected Member Functions

Protected Attributes

Detailed Description

Member Typedef Documentation

◆ LayerType

Member Enumeration Documentation

◆ IdentifyMode

◆ Type

Constructor & Destructor Documentation

◆ QgsMapToolIdentify()

◆ ~QgsMapToolIdentify()

Member Function Documentation

◆ activate()

◆ canvasMoveEvent()

◆ canvasPressEvent()

◆ canvasReleaseEvent()

◆ changedRasterResults

◆ deactivate()

◆ derivedAttributesForPoint()

◆ flags()

◆ formatChanged

◆ fromElevationProfileLayerIdentificationToIdentifyResults()

◆ fromPointCloudIdentificationToIdentifyResults()

◆ identify() [1/5]

◆ identify() [2/5]

◆ identify() [3/5]

◆ identify() [4/5]

◆ identify() [5/5]

◆ identifyLayer()

◆ identifyMenu()

◆ identifyMeshLayer()

◆ identifyMessage

◆ identifyProgress

◆ identifyRasterLayer()

◆ identifyVectorLayer()

◆ restoreCanvasPropertiesOverrides()

◆ setCanvasPropertiesOverrides()

Member Data Documentation

◆ mIdentifyMenu