QGIS API Documentation  3.21.0-Master (56b4176581)
Public Types | Signals | Public Member Functions | Static Public Member Functions | Protected Member Functions | Protected Attributes | List of all members
QgsMapTool Class Reference

Abstract base class for all map tools. More...

#include <qgsmaptool.h>

Inheritance diagram for QgsMapTool:
Inheritance graph
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Public Types

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...
 

Signals

void activated ()
 signal emitted once the map tool is activated More...
 
void deactivated ()
 signal emitted once the map tool is deactivated More...
 
void messageDiscarded ()
 emit signal to clear previous message More...
 
void messageEmitted (const QString &message, Qgis::MessageLevel=Qgis::MessageLevel::Info)
 emit a message More...
 

Public Member Functions

 ~QgsMapTool () override
 
QAction * action ()
 Returns associated action with map tool or nullptr if no action is associated. More...
 
virtual void activate ()
 called when set as currently active map tool More...
 
QAbstractButton * button ()
 Returns associated button with map tool or nullptr if no button is associated. More...
 
QgsMapCanvascanvas () const
 returns pointer to the tool's map canvas More...
 
virtual void canvasDoubleClickEvent (QgsMapMouseEvent *e)
 Mouse double-click event for overriding. Default implementation does nothing. More...
 
virtual void canvasMoveEvent (QgsMapMouseEvent *e)
 Mouse move event for overriding. Default implementation does nothing. More...
 
virtual void canvasPressEvent (QgsMapMouseEvent *e)
 Mouse press event for overriding. Default implementation does nothing. More...
 
virtual void canvasReleaseEvent (QgsMapMouseEvent *e)
 Mouse release event for overriding. Default implementation does nothing. More...
 
virtual bool canvasToolTipEvent (QHelpEvent *e)
 Tooltip event for overriding. More...
 
virtual void clean ()
 convenient method to clean members More...
 
virtual void deactivate ()
 called when map tool is being deactivated More...
 
virtual Flags flags () const
 Returns the flags for the map tool. More...
 
virtual bool gestureEvent (QGestureEvent *e)
 gesture event for overriding. Default implementation does nothing. More...
 
bool isActive () const
 Returns if the current map tool active on the map canvas. More...
 
virtual void keyPressEvent (QKeyEvent *e)
 Key event for overriding. Default implementation does nothing. More...
 
virtual void keyReleaseEvent (QKeyEvent *e)
 Key event for overriding. Default implementation does nothing. More...
 
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. More...
 
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. More...
 
void setAction (QAction *action)
 Use this to associate a QAction to this maptool. More...
 
void setButton (QAbstractButton *button)
 Use this to associate a button to this maptool. More...
 
virtual void setCursor (const QCursor &cursor)
 Sets a user defined cursor. More...
 
QString toolName ()
 Emit map tool changed with the old tool. More...
 
virtual void wheelEvent (QWheelEvent *e)
 Mouse wheel event for overriding. Default implementation does nothing. More...
 

Static Public Member Functions

static double searchRadiusMM ()
 Gets search radius in mm. More...
 
static double searchRadiusMU (const QgsRenderContext &context)
 Gets search radius in map units for given context. More...
 
static double searchRadiusMU (QgsMapCanvas *canvas)
 Gets search radius in map units for given canvas. More...
 

Protected Member Functions

 QgsMapTool (QgsMapCanvas *canvas)
 Constructor takes a map canvas as a parameter. More...
 
void setToolName (const QString &name)
 Sets the tool's name. More...
 
QPoint toCanvasCoordinates (const QgsPointXY &point) const
 Transforms a point from map coordinates to screen coordinates. More...
 
QgsPointXY toLayerCoordinates (const QgsMapLayer *layer, const QgsPointXY &point)
 Transforms a point from map coordinates to layer coordinates. More...
 
QgsRectangle toLayerCoordinates (const QgsMapLayer *layer, const QgsRectangle &rect)
 Transforms a rect from map coordinates to layer coordinates. More...
 
QgsPointXY toLayerCoordinates (const QgsMapLayer *layer, QPoint point)
 Transforms a point from screen coordinates to layer coordinates. More...
 
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). More...
 
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). More...
 
QgsPointXY toMapCoordinates (QPoint point)
 Transforms a point from screen coordinates to map coordinates. More...
 

Protected Attributes

QAction * mAction = nullptr
 Optional pointer to an action that will be checked on map tool activation and unchecked on map tool deactivation. More...
 
QAbstractButton * mButton = nullptr
 Optional pointer to a button that will be checked on map tool activation and unchecked on map tool deactivation. More...
 
QgsMapCanvasmCanvas = nullptr
 The pointer to the map canvas. More...
 
QCursor mCursor
 The cursor used in the map tool. More...
 
QString mToolName
 The translated name of the map tool. More...
 

Detailed Description

Abstract base class for all map tools.

Map tools are user interactive tools for manipulating the map canvas. For example map pan and zoom features are implemented as map tools.

Definition at line 65 of file qgsmaptool.h.

Member Enumeration Documentation

◆ Flag

Enumeration of flags that adjust the way the map tool operates.

Since
QGIS 2.16
Enumerator
Transient 

Indicates that this map tool performs a transient (one-off) operation. If it does, the tool can be operated once and then a previous map tool automatically restored.

EditTool 

Map tool is an edit tool, which can only be used when layer is editable.

AllowZoomRect 

Allow zooming by rectangle (by holding shift and dragging) while the tool is active.

ShowContextMenu 

Show a context menu when right-clicking with the tool (since QGIS 3.14). See populateContextMenu().

Definition at line 93 of file qgsmaptool.h.

Constructor & Destructor Documentation

◆ ~QgsMapTool()

QgsMapTool::~QgsMapTool ( )
override

Definition at line 35 of file qgsmaptool.cpp.

◆ QgsMapTool()

QgsMapTool::QgsMapTool ( QgsMapCanvas canvas)
protected

Constructor takes a map canvas as a parameter.

Definition at line 27 of file qgsmaptool.cpp.

Member Function Documentation

◆ action()

QAction * QgsMapTool::action ( )

Returns associated action with map tool or nullptr if no action is associated.

Definition at line 130 of file qgsmaptool.cpp.

◆ activate()

void QgsMapTool::activate ( )
virtual

called when set as currently active map tool

Reimplemented in QgsMapToolPan, QgsMapToolIdentify, QgsMapToolExtent, QgsMapToolDigitizeFeature, QgsMapToolCapture, and QgsMapToolAdvancedDigitizing.

Definition at line 84 of file qgsmaptool.cpp.

◆ activated

void QgsMapTool::activated ( )
signal

signal emitted once the map tool is activated

◆ button()

QAbstractButton * QgsMapTool::button ( )

Returns associated button with map tool or nullptr if no button is associated.

Definition at line 145 of file qgsmaptool.cpp.

◆ canvas()

QgsMapCanvas * QgsMapTool::canvas ( ) const

returns pointer to the tool's map canvas

Definition at line 205 of file qgsmaptool.cpp.

◆ canvasDoubleClickEvent()

void QgsMapTool::canvasDoubleClickEvent ( QgsMapMouseEvent e)
virtual

Mouse double-click event for overriding. Default implementation does nothing.

Reimplemented in QgsMapToolModifyAnnotation, and QgsMapToolPan.

Definition at line 163 of file qgsmaptool.cpp.

◆ canvasMoveEvent()

void QgsMapTool::canvasMoveEvent ( QgsMapMouseEvent e)
virtual

Mouse move event for overriding. Default implementation does nothing.

Reimplemented in QgsMapToolZoom, QgsMapToolPan, QgsMapToolIdentify, QgsMapToolExtent, QgsMapToolEmitPoint, and QgsMapToolAdvancedDigitizing.

Definition at line 158 of file qgsmaptool.cpp.

◆ canvasPressEvent()

void QgsMapTool::canvasPressEvent ( QgsMapMouseEvent e)
virtual

Mouse press event for overriding. Default implementation does nothing.

Reimplemented in QgsMapToolZoom, QgsMapToolPan, QgsMapToolIdentify, QgsMapToolExtent, QgsMapToolEmitPoint, and QgsMapToolAdvancedDigitizing.

Definition at line 168 of file qgsmaptool.cpp.

◆ canvasReleaseEvent()

void QgsMapTool::canvasReleaseEvent ( QgsMapMouseEvent e)
virtual

Mouse release event for overriding. Default implementation does nothing.

Reimplemented in QgsMapToolZoom, QgsMapToolPan, QgsMapToolIdentifyFeature, QgsMapToolIdentify, QgsMapToolExtent, QgsMapToolEmitPoint, and QgsMapToolAdvancedDigitizing.

Definition at line 173 of file qgsmaptool.cpp.

◆ canvasToolTipEvent()

bool QgsMapTool::canvasToolTipEvent ( QHelpEvent *  e)
virtual

Tooltip event for overriding.

Default implementation does nothing. Returns whether the event was handled by the tool and should not be propagated further.

Since
QGIS 3.22

Definition at line 199 of file qgsmaptool.cpp.

◆ clean()

void QgsMapTool::clean ( )
virtual

convenient method to clean members

Reimplemented in QgsMapToolCapture.

Definition at line 110 of file qgsmaptool.cpp.

◆ deactivate()

void QgsMapTool::deactivate ( )
virtual

◆ deactivated

void QgsMapTool::deactivated ( )
signal

signal emitted once the map tool is deactivated

◆ flags()

virtual Flags QgsMapTool::flags ( ) const
inlinevirtual

Returns the flags for the map tool.

Since
QGIS 2.16

Reimplemented in QgsMapToolZoom, QgsMapToolPan, QgsMapToolIdentify, QgsMapToolExtent, QgsMapToolEmitPoint, and QgsMapToolEdit.

Definition at line 108 of file qgsmaptool.h.

◆ gestureEvent()

bool QgsMapTool::gestureEvent ( QGestureEvent *  e)
virtual

gesture event for overriding. Default implementation does nothing.

Reimplemented in QgsMapToolPan.

Definition at line 193 of file qgsmaptool.cpp.

◆ isActive()

bool QgsMapTool::isActive ( ) const

Returns if the current map tool active on the map canvas.

Since
QGIS 3.4

Definition at line 135 of file qgsmaptool.cpp.

◆ keyPressEvent()

void QgsMapTool::keyPressEvent ( QKeyEvent *  e)
virtual

Key event for overriding. Default implementation does nothing.

Reimplemented in QgsMapToolModifyAnnotation, QgsMapToolZoom, QgsMapToolIdentifyFeature, and QgsMapToolCapture.

Definition at line 183 of file qgsmaptool.cpp.

◆ keyReleaseEvent()

void QgsMapTool::keyReleaseEvent ( QKeyEvent *  e)
virtual

Key event for overriding. Default implementation does nothing.

Reimplemented in QgsMapToolZoom.

Definition at line 188 of file qgsmaptool.cpp.

◆ messageDiscarded

void QgsMapTool::messageDiscarded ( )
signal

emit signal to clear previous message

◆ messageEmitted

void QgsMapTool::messageEmitted ( const QString &  message,
Qgis::MessageLevel  = Qgis::MessageLevel::Info 
)
signal

emit a message

◆ populateContextMenu()

void QgsMapTool::populateContextMenu ( QMenu *  menu)
virtual

Allows the tool to populate and customize the given menu, prior to showing it in response to a right-mouse button click.

menu will be initially populated with a set of default, generic actions. Any new actions added to the menu should be correctly parented to menu.

The default implementation does nothing.

Note
The context menu is only shown when the ShowContextMenu flag is present in flags().
Since
QGIS 3.14

Definition at line 239 of file qgsmaptool.cpp.

◆ populateContextMenuWithEvent()

bool QgsMapTool::populateContextMenuWithEvent ( QMenu *  menu,
QgsMapMouseEvent event 
)
virtual

Allows the tool to populate and customize the given menu, prior to showing it in response to a right-mouse button click.

menu will be initially populated with a set of default, generic actions. Any new actions added to the menu should be correctly parented to menu.

A pointer to the map mouse event can be provided to allow particular behavior depending on the map tool.

This method can return true to inform the caller that the menu was effectively populated.

The default implementation does nothing and returns false.

Note
The context menu is only shown when the ShowContextMenu flag is present in flags().
Since
QGIS 3.18

Definition at line 245 of file qgsmaptool.cpp.

◆ searchRadiusMM()

double QgsMapTool::searchRadiusMM ( )
static

Gets search radius in mm.

Used by identify, tip etc. The values is currently set in identify tool options (move somewhere else?) and defaults to Qgis::DEFAULT_SEARCH_RADIUS_MM.

Since
QGIS 2.3

Definition at line 210 of file qgsmaptool.cpp.

◆ searchRadiusMU() [1/2]

double QgsMapTool::searchRadiusMU ( const QgsRenderContext context)
static

Gets search radius in map units for given context.

Used by identify, tip etc. The values is calculated from searchRadiusMM().

Since
QGIS 2.3

Definition at line 222 of file qgsmaptool.cpp.

◆ searchRadiusMU() [2/2]

double QgsMapTool::searchRadiusMU ( QgsMapCanvas canvas)
static

Gets search radius in map units for given canvas.

Used by identify, tip etc. The values is calculated from searchRadiusMM().

Since
QGIS 2.3

Definition at line 227 of file qgsmaptool.cpp.

◆ setAction()

void QgsMapTool::setAction ( QAction *  action)

Use this to associate a QAction to this maptool.

Then when the setMapTool method of mapcanvas is called the action state will be set to on. Usually this will cause e.g. a toolbutton to appear pressed in and the previously used toolbutton to pop out.

Definition at line 115 of file qgsmaptool.cpp.

◆ setButton()

void QgsMapTool::setButton ( QAbstractButton *  button)

Use this to associate a button to this maptool.

It has the same meaning as setAction() function except it works with a button instead of an QAction.

Definition at line 140 of file qgsmaptool.cpp.

◆ setCursor()

void QgsMapTool::setCursor ( const QCursor &  cursor)
virtual

Sets a user defined cursor.

Definition at line 150 of file qgsmaptool.cpp.

◆ setToolName()

void QgsMapTool::setToolName ( const QString &  name)
protected

Sets the tool's name.

See also
toolName()
Since
QGIS 3.20

Definition at line 79 of file qgsmaptool.cpp.

◆ toCanvasCoordinates()

QPoint QgsMapTool::toCanvasCoordinates ( const QgsPointXY point) const
protected

Transforms a point from map coordinates to screen coordinates.

Definition at line 72 of file qgsmaptool.cpp.

◆ toLayerCoordinates() [1/3]

QgsPointXY QgsMapTool::toLayerCoordinates ( const QgsMapLayer layer,
const QgsPointXY point 
)
protected

Transforms a point from map coordinates to layer coordinates.

Definition at line 57 of file qgsmaptool.cpp.

◆ toLayerCoordinates() [2/3]

QgsRectangle QgsMapTool::toLayerCoordinates ( const QgsMapLayer layer,
const QgsRectangle rect 
)
protected

Transforms a rect from map coordinates to layer coordinates.

Definition at line 67 of file qgsmaptool.cpp.

◆ toLayerCoordinates() [3/3]

QgsPointXY QgsMapTool::toLayerCoordinates ( const QgsMapLayer layer,
QPoint  point 
)
protected

Transforms a point from screen coordinates to layer coordinates.

Definition at line 51 of file qgsmaptool.cpp.

◆ toMapCoordinates() [1/3]

QgsPoint QgsMapTool::toMapCoordinates ( const QgsMapLayer layer,
const QgsPoint point 
)
protected

Transforms a point from layer coordinates to map coordinates (which is different in case reprojection is used).

Note
This method is available in the Python bindings as toMapCoordinatesV2.

Definition at line 46 of file qgsmaptool.cpp.

◆ toMapCoordinates() [2/3]

QgsPointXY QgsMapTool::toMapCoordinates ( const QgsMapLayer layer,
const QgsPointXY point 
)
protected

Transforms a point from layer coordinates to map coordinates (which is different in case reprojection is used).

Definition at line 62 of file qgsmaptool.cpp.

◆ toMapCoordinates() [3/3]

QgsPointXY QgsMapTool::toMapCoordinates ( QPoint  point)
protected

Transforms a point from screen coordinates to map coordinates.

Definition at line 41 of file qgsmaptool.cpp.

◆ toolName()

QString QgsMapTool::toolName ( )
inline

Emit map tool changed with the old tool.

See also
setToolName()
Since
QGIS 2.3

Definition at line 189 of file qgsmaptool.h.

◆ wheelEvent()

void QgsMapTool::wheelEvent ( QWheelEvent *  e)
virtual

Mouse wheel event for overriding. Default implementation does nothing.

Definition at line 178 of file qgsmaptool.cpp.

Member Data Documentation

◆ mAction

QAction* QgsMapTool::mAction = nullptr
protected

Optional pointer to an action that will be checked on map tool activation and unchecked on map tool deactivation.

Definition at line 313 of file qgsmaptool.h.

◆ mButton

QAbstractButton* QgsMapTool::mButton = nullptr
protected

Optional pointer to a button that will be checked on map tool activation and unchecked on map tool deactivation.

Definition at line 319 of file qgsmaptool.h.

◆ mCanvas

QgsMapCanvas* QgsMapTool::mCanvas = nullptr
protected

The pointer to the map canvas.

Definition at line 304 of file qgsmaptool.h.

◆ mCursor

QCursor QgsMapTool::mCursor
protected

The cursor used in the map tool.

Definition at line 307 of file qgsmaptool.h.

◆ mToolName

QString QgsMapTool::mToolName
protected

The translated name of the map tool.

Definition at line 322 of file qgsmaptool.h.


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