Class: QgsMapTool¶

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.

Class Hierarchy¶

Base classes¶

QObject

Subclasses¶

`QgsMapToolEdit`	Base class for map tools that edit vector geometry.
`QgsMapToolEmitPoint`	A map tool that simply emits a point when clicking on the map.
`QgsMapToolExtent`	A map tool that emits an extent from a rectangle drawn onto the map canvas.
`QgsMapToolIdentify`	Map tool for identifying features in layers.
`QgsMapToolPan`	A map tool for panning the map.
`QgsMapToolZoom`	A map tool for zooming into the map.

Methods

`action`	Returns associated action with map tool or `None` if no action is associated
`button`	Returns associated button with map tool or `None` if no button is associated
`canvas`	returns pointer to the tool's map canvas
`isActive`	Returns if the current map tool active on the map canvas
`layer`	Returns the map layer with the matching ID, or `None` if no layers could be found.
`setAction`	Use this to associate a QAction to this maptool.
`setButton`	Use this to associate a button to this maptool.
`setToolName`	Sets the tool's name.
`toCanvasCoordinates`	Transforms a point from map coordinates to screen coordinates.
`toLayerCoordinates`	Transforms a point from screen coordinates to layer coordinates.
`toLayerCoordinatesV2`	Transforms a point from map coordinates to layer coordinates.
`toMapCoordinates`	Transforms a point from screen coordinates to map coordinates.
`toMapCoordinatesV2`	Transforms a point from layer coordinates to map coordinates (which is different in case reprojection is used).
`toolName`	Emit map tool changed with the old tool

Virtual Methods

In PyQGIS, only methods marked as virtual can be safely overridden in a Python subclass of QgsMapTool. See the FAQ for more details.

`activate`	called when set as currently active map tool
`canvasDoubleClickEvent`	Mouse double-click event for overriding.
`canvasMoveEvent`	Mouse move event for overriding.
`canvasPressEvent`	Mouse press event for overriding.
`canvasReleaseEvent`	Mouse release event for overriding.
`canvasToolTipEvent`	Tooltip event for overriding.
`clean`	convenient method to clean members
`deactivate`	called when map tool is being deactivated
`flags`	Returns the flags for the map tool.
`gestureEvent`	gesture event for overriding.
`keyPressEvent`	Key event for overriding.
`keyReleaseEvent`	Key event for overriding.
`populateContextMenu`	Allows the tool to populate and customize the given menu, prior to showing it in response to a right-mouse button click.
`populateContextMenuWithEvent`	Allows the tool to populate and customize the given menu, prior to showing it in response to a right-mouse button click.
`reactivate`	Called when the map tool is being activated while it is already active.
`setCursor`	Sets a user defined cursor
`wheelEvent`	Mouse wheel event for overriding.

Static Methods

`searchRadiusMM`	Gets search radius in mm.
`searchRadiusMU`	Gets search radius in map units for given context.

Signals

`activated`	Emitted when the map tool is activated.
`deactivated`	Emitted when the map tool is deactivated.
`messageDiscarded`	Emitted when the previous message from the tool should be cleared from the application message bar.
`messageEmitted`	Emitted when a message should be shown to the user in the application message bar.
`reactivated`	Emitted when the map tool is activated, while it is already active.

Attributes

`AllowZoomRect`
`EditTool`
`ShowContextMenu`
`Transient`

class qgis.gui.QgsMapTool[source]¶

Bases: QObject

__init__(canvas: QgsMapCanvas | None)

Constructor takes a map canvas as a parameter.

Parameters:: canvas (Optional[QgsMapCanvas])

AllowZoomRect = 8¶

EditTool = 4¶

class Flag¶: Bases: int

class Flags¶
class Flags(f: QgsMapTool.Flags | QgsMapTool.Flag)
class Flags(a0: QgsMapTool.Flags): Bases: object

ShowContextMenu = 16¶

Transient = 2¶

action(self) → QAction | None[source]¶

Returns associated action with map tool or None if no action is associated

Return type:: Optional[QAction]

virtual activate(self)[source]¶: called when set as currently active map tool

signal activated[source]¶: Emitted when the map tool is activated.

See also

deactivated()

button(self) → QAbstractButton | None[source]¶

Returns associated button with map tool or None if no button is associated

Return type:: Optional[QAbstractButton]

canvas(self) → QgsMapCanvas | None[source]¶

returns pointer to the tool’s map canvas

Return type:: Optional[QgsMapCanvas]

virtual canvasDoubleClickEvent(self, e: QgsMapMouseEvent | None)[source]¶

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

Parameters:: e (Optional[QgsMapMouseEvent])

virtual canvasMoveEvent(self, e: QgsMapMouseEvent | None)[source]¶

Mouse move event for overriding. Default implementation does nothing.

Parameters:: e (Optional[QgsMapMouseEvent])

virtual canvasPressEvent(self, e: QgsMapMouseEvent | None)[source]¶

Mouse press event for overriding. Default implementation does nothing.

Parameters:: e (Optional[QgsMapMouseEvent])

virtual canvasReleaseEvent(self, e: QgsMapMouseEvent | None)[source]¶

Mouse release event for overriding. Default implementation does nothing.

Parameters:: e (Optional[QgsMapMouseEvent])

virtual canvasToolTipEvent(self, e: QHelpEvent | None) → bool[source]¶

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

Added in version 3.22.

Parameters:: e (Optional[QHelpEvent])
Return type:: bool

virtual clean(self)[source]¶: convenient method to clean members

virtual deactivate(self)[source]¶: called when map tool is being deactivated

signal deactivated[source]¶: Emitted when the map tool is deactivated.

See also

activated()

virtual flags(self) → QgsMapTool.Flags[source]¶

Returns the flags for the map tool.

Return type:: QgsMapTool.Flags

virtual gestureEvent(self, e: QGestureEvent | None) → bool[source]¶

gesture event for overriding. Default implementation does nothing.

Parameters:: e (Optional[QGestureEvent])
Return type:: bool

isActive(self) → bool[source]¶

Returns if the current map tool active on the map canvas

Added in version 3.4.

Return type:: bool

virtual keyPressEvent(self, e: QKeyEvent | None)[source]¶

Key event for overriding. Default implementation does nothing.

Parameters:: e (Optional[QKeyEvent])

virtual keyReleaseEvent(self, e: QKeyEvent | None)[source]¶

Key event for overriding. Default implementation does nothing.

Parameters:: e (Optional[QKeyEvent])

layer(self, id: str | None) → QgsMapLayer | None[source]¶

Returns the map layer with the matching ID, or None if no layers could be found.

This method searches both layers associated with the map canvas (see QgsMapCanvas.layers()) and layers from the QgsProject associated with the canvas. It can be used to resolve layer IDs to layers which may be visible in the canvas, but not associated with a QgsProject.

Added in version 3.22.

Parameters:: id (Optional[str])
Return type:: Optional[QgsMapLayer]

signal messageDiscarded[source]¶: Emitted when the previous message from the tool should be cleared from the application message bar.

See also

messageEmitted()

signal messageEmitted(message: str, level: Qgis.MessageLevel = Qgis.MessageLevel.Info)[source]¶

Emitted when a message should be shown to the user in the application message bar.