Base class for all map layer types. More...

#include <qgsmaplayer.h>

Inheritance diagram for QgsMapLayer:

Public Types
enum	LayerType { VectorLayer, RasterLayer, PluginLayer }
	Layers enum defining the types of layers that can be added to a map. More...

Public Slots
Q_DECL_DEPRECATED void	clearCacheImage ()
	Clear cached image.
virtual void	invalidTransformInput ()
	Event handler for when a coordinate transform fails due to bad vertex error.
virtual QString	metadata ()
	Obtain Metadata for this layer.
void	setMaximumScale (const float theMaxScale)
	Sets the maximum scale denominator at which the layer will be visible.
void	setMinimumScale (const float theMinScale)
	Sets the minimum scale denominator at which the layer will be visible.
void	setScaleBasedVisibility (const bool enabled)
	Sets whether scale based visibility is enabled for the layer.
virtual QDateTime	timestamp () const
	Time stamp of data source in the moment when data/metadata were loaded by provider.
Q_DECL_DEPRECATED void	toggleScaleBasedVisibility (bool theVisibilityFlag)
	Accessor for the scale based visilibility flag.
void	triggerRepaint ()
	Will advice the map canvas (and any other interested party) that this layer requires to be repainted.

Signals
void	blendModeChanged (const QPainter::CompositionMode &blendMode)
	Signal emitted when the blend mode is changed, through QgsMapLayer::setBlendMode()
void	dataChanged ()
	data of layer changed
void	drawingProgress (int theProgress, int theTotalSteps)
void	layerCrsChanged ()
	Emit a signal that layer's CRS has been reset.
void	layerNameChanged ()
	Emit a signal that the layer name has been changed.
void	legendChanged ()
	Signal emitted when legend of the layer has changed.
void	recalculateExtents ()
	This is used to send a request that any mapcanvas using this layer update its extents.
void	rendererChanged ()
	Signal emitted when renderer is changed.
void	repaintRequested ()
	By emitting this signal the layer tells that either appearance or content have been changed and any view showing the rendered layer should refresh itself.
void	screenUpdateRequested ()
void	statusChanged (QString theStatus)
	Emit a signal with status (e.g.

Public Member Functions
	QgsMapLayer (QgsMapLayer::LayerType type=VectorLayer, QString lyrname=QString::null, QString source=QString::null)
	Constructor.
virtual	~QgsMapLayer ()
	Destructor.
const QString &	abstract () const
const QString &	attribution () const
const QString &	attributionUrl () const
QPainter::CompositionMode	blendMode () const
	Read blend mode for layer.
Q_DECL_DEPRECATED QImage *	cacheImage ()
virtual QgsMapLayerRenderer *	createMapRenderer (QgsRenderContext &rendererContext)
	Return new instance of QgsMapLayerRenderer that will be used for rendering of given context.
const QgsCoordinateReferenceSystem &	crs () const
	Returns layer's spatial reference system.
QVariant	customProperty (const QString &value, const QVariant &defaultValue=QVariant()) const
	Read a custom property from layer.
const QString &	dataUrl () const
const QString &	dataUrlFormat () const
virtual bool	draw (QgsRenderContext &rendererContext)
	This is the method that does the actual work of drawing the layer onto a paint device.
virtual void	drawLabels (QgsRenderContext &rendererContext)
	Draw labels.
virtual QgsError	error () const
	Get current status error.
virtual void	exportNamedStyle (QDomDocument &doc, QString &errorMsg)
	Export the properties of this layer as named style in a QDomDocument.
virtual void	exportSldStyle (QDomDocument &doc, QString &errorMsg)
	Export the properties of this layer as SLD style in a QDomDocument.
virtual QgsRectangle	extent ()
	Return the extent of the layer.
bool	hasScaleBasedVisibility () const
	Returns whether scale based visibility is enabled for the layer.
QString	id () const
	Get this layer's unique ID, this ID is used to access this layer from map layer registry.
virtual bool	importNamedStyle (QDomDocument &doc, QString &errorMsg)
	Import the properties of this layer from a QDomDocument.
virtual bool	isEditable () const
	True if the layer can be edited.
bool	isValid ()
const QString &	keywordList () const
virtual Q_DECL_DEPRECATED QString	lastError ()
virtual Q_DECL_DEPRECATED QString	lastErrorTitle ()
QgsMapLayerLegend *	legend () const
	Can be null.
const QString &	legendUrl () const
const QString &	legendUrlFormat () const
virtual QString	loadDefaultStyle (bool &theResultFlag)
	Retrieve the default style for this layer if one exists (either as a .qml file on disk or as a record in the users style table in their personal qgis.db)
virtual QString	loadNamedStyle (const QString &theURI, bool &theResultFlag)
	Retrieve a named style for this layer if one exists (either as a .qml file on disk or as a record in the users style table in their personal qgis.db)
virtual bool	loadNamedStyleFromDb (const QString &db, const QString &theURI, QString &qml)
virtual QString	loadSldStyle (const QString &theURI, bool &theResultFlag)
float	maximumScale () const
	Returns the maximum scale denominator at which the layer is visible.
const QString &	metadataUrl () const
const QString &	metadataUrlFormat () const
const QString &	metadataUrlType () const
float	minimumScale () const
	Returns the minimum scale denominator at which the layer is visible.
const QString &	name () const
	Get the display name of the layer.
virtual Q_DECL_DEPRECATED void	onCacheImageDelete ()
const QString &	originalName () const
	Get the original name of the layer.
QString	publicSource () const
bool	readLayerXML (const QDomElement &layerElement)
	sets state from Dom document
virtual bool	readSld (const QDomNode &node, QString &errorMessage)
virtual bool	readSymbology (const QDomNode &node, QString &errorMessage)=0
	Read the symbology for the current layer from the Dom node supplied.
virtual void	reload ()
	Synchronises with changes in the datasource.
void	removeCustomProperty (const QString &key)
	Remove a custom property from layer.
virtual QString	saveDefaultStyle (bool &theResultFlag)
	Save the properties of this layer as the default style (either as a .qml file on disk or as a record in the users style table in their personal qgis.db)
virtual QString	saveNamedStyle (const QString &theURI, bool &theResultFlag)
	Save the properties of this layer as a named style (either as a .qml file on disk or as a record in the users style table in their personal qgis.db)
virtual QString	saveSldStyle (const QString &theURI, bool &theResultFlag)
void	setAbstract (const QString &abstract)
void	setAttribution (const QString &attrib)
void	setAttributionUrl (const QString &attribUrl)
void	setBlendMode (const QPainter::CompositionMode &blendMode)
	Write blend mode for layer.
Q_DECL_DEPRECATED void	setCacheImage (QImage *)
void	setCrs (const QgsCoordinateReferenceSystem &srs, bool emitSignal=true)
	Sets layer's spatial reference system.
void	setCustomProperty (const QString &key, const QVariant &value)
	Set a custom property for layer.
void	setDataUrl (const QString &dataUrl)
void	setDataUrlFormat (const QString &dataUrlFormat)
void	setKeywordList (const QString &keywords)
void	setLayerName (const QString &name)
	Set the display name of the layer.
virtual void	setLayerOrder (const QStringList &layers)
	Reorders the previously selected sublayers of this layer from bottom to top (Useful for providers that manage their own layers, such as WMS)
void	setLegend (QgsMapLayerLegend *legend)
	Assign a legend controller to the map layer.
void	setLegendUrl (const QString &legendUrl)
void	setLegendUrlFormat (const QString &legendUrlFormat)
void	setMetadataUrl (const QString &metaUrl)
void	setMetadataUrlFormat (const QString &metaUrlFormat)
void	setMetadataUrlType (const QString &metaUrlType)
virtual void	setSubLayerVisibility (QString name, bool vis)
	Set the visibility of the given sublayer name.
void	setTitle (const QString &title)
const QString &	source () const
	Returns the source for the layer.
QgsMapLayerStyleManager *	styleManager () const
	Get access to the layer's style manager.
virtual QString	styleURI ()
	Retrieve the style URI for this layer (either as a .qml file on disk or as a record in the users style table in their personal qgis.db)
virtual QStringList	subLayers () const
	Returns the sublayers of this layer (Useful for providers that manage their own layers, such as WMS)
const QString &	title () const
QgsMapLayer::LayerType	type () const
	Get the type of the layer.
QUndoStack *	undoStack ()
	Return pointer to layer's undo stack.
bool	writeLayerXML (QDomElement &layerElement, QDomDocument &document, QString relativeBasePath=QString::null)
	stores state in Dom node
virtual bool	writeSymbology (QDomNode &node, QDomDocument &doc, QString &errorMessage) const =0
	Write the symbology for the layer into the docment provided.

Static Public Member Functions
static QDomDocument	asLayerDefinition (QList< QgsMapLayer * > layers, QString relativeBasePath=QString::null)
	Returns the given layer as a layer definition document Layer definitions store the data source as well as styling and custom properties.
static QString	capitaliseLayerName (const QString &name)
	A convenience function to (un)capitalise the layer name.
static QList< QgsMapLayer * >	fromLayerDefinition (QDomDocument &document)
	Creates a new layer from a layer defininition document.
static QList< QgsMapLayer * >	fromLayerDefinitionFile (const QString &qlrfile)

Protected Member Functions
void	appendError (const QgsErrorMessage &theMessage)
	Add error message.
void	readCustomProperties (const QDomNode &layerNode, const QString &keyStartsWith="")
	Read custom properties from project file.
void	readStyleManager (const QDomNode &layerNode)
	Read style manager's configuration (if any).
virtual bool	readXml (const QDomNode &layer_node)
	called by readLayerXML(), used by children to read state specific to them from project files.
void	setError (const QgsError &theError)
	Set error message.
virtual void	setExtent (const QgsRectangle &rect)
	Set the extent.
void	setValid (bool valid)
	set whether layer is valid or not - should be used in constructor.
void	writeCustomProperties (QDomNode &layerNode, QDomDocument &doc) const
	Write custom properties to project file.
void	writeStyleManager (QDomNode &layerNode, QDomDocument &doc) const
	Write style manager's configuration (if exists).
virtual bool	writeXml (QDomNode &layer_node, QDomDocument &document)
	called by writeLayerXML(), used by children to write state specific to them to project files.

Protected Attributes
QString	mAbstract
	Description of the layer.
QString	mAttribution
	Attribution of the layer.
QString	mAttributionUrl
QString	mDataSource
	data source description string, varies by layer type
QString	mDataUrl
	DataUrl of the layer.
QString	mDataUrlFormat
QgsError	mError
	Error.
QgsRectangle	mExtent
	Extent of the layer.
QString	mKeywordList
QString	mLayerName
	Name of the layer - used for display.
QString	mLayerOrigName
	Original name of the layer.
QString	mLegendUrl
	WMS legend.
QString	mLegendUrlFormat
QString	mMetadataUrl
	MetadataUrl of the layer.
QString	mMetadataUrlFormat
QString	mMetadataUrlType
QString	mTitle
bool	mValid
	Indicates if the layer is valid and can be drawn.

Detailed Description

Base class for all map layer types.

This is the base class for all map layer types (vector, raster).

Definition at line 49 of file qgsmaplayer.h.

Member Enumeration Documentation

enum QgsMapLayer::LayerType

Layers enum defining the types of layers that can be added to a map.

Enumerator:

VectorLayer
RasterLayer
PluginLayer

Definition at line 55 of file qgsmaplayer.h.

Constructor & Destructor Documentation

QgsMapLayer::QgsMapLayer	(	QgsMapLayer::LayerType	type = `VectorLayer`,
		QString	lyrname = `QString::null`,
		QString	source = `QString::null`
	)

Constructor.

Parameters

type	Type of layer as defined in QgsMapLayer::LayerType enum
lyrname	Display Name of the layer
source	datasource of layer

Definition at line 49 of file qgsmaplayer.cpp.

QgsMapLayer::~QgsMapLayer ( )

virtual

Destructor.

Definition at line 85 of file qgsmaplayer.cpp.

Member Function Documentation

const QString& QgsMapLayer::abstract ( ) const

inline

Definition at line 97 of file qgsmaplayer.h.

void QgsMapLayer::appendError ( const QgsErrorMessage & theMessage )

inlineprotected

Add error message.

Definition at line 563 of file qgsmaplayer.h.

QDomDocument QgsMapLayer::asLayerDefinition	(	QList< QgsMapLayer * >	layers,
		QString	relativeBasePath = `QString::null`
	)

static

Returns the given layer as a layer definition document Layer definitions store the data source as well as styling and custom properties.

Layer definitions can be used to load a layer and styling all from a single file.

Definition at line 617 of file qgsmaplayer.cpp.

const QString& QgsMapLayer::attribution ( ) const

inline

Definition at line 110 of file qgsmaplayer.h.

const QString& QgsMapLayer::attributionUrl ( ) const

inline

Definition at line 112 of file qgsmaplayer.h.

QPainter::CompositionMode QgsMapLayer::blendMode ( ) const

Read blend mode for layer.

Definition at line 148 of file qgsmaplayer.cpp.

void QgsMapLayer::blendModeChanged ( const QPainter::CompositionMode & blendMode )

signal

Signal emitted when the blend mode is changed, through QgsMapLayer::setBlendMode()

Q_DECL_DEPRECATED QImage* QgsMapLayer::cacheImage ( )

inline

Deprecated:: since 2.4 - returns NULL

Definition at line 382 of file qgsmaplayer.h.

QString QgsMapLayer::capitaliseLayerName ( const QString & name )

static

A convenience function to (un)capitalise the layer name.

Definition at line 839 of file qgsmaplayer.cpp.

void QgsMapLayer::clearCacheImage ( )

slot

Clear cached image.

Deprecated:: in 2.4 - use triggerRepaint() - caches automatically listen to repaintRequested() signal to invalidate the cached image

Definition at line 1461 of file qgsmaplayer.cpp.

virtual QgsMapLayerRenderer* QgsMapLayer::createMapRenderer ( QgsRenderContext & rendererContext )

inlinevirtual

Return new instance of QgsMapLayerRenderer that will be used for rendering of given context.

Note: added in 2.4

Reimplemented in QgsVectorLayer, QgsRasterLayer, and QgsPluginLayer.

Definition at line 134 of file qgsmaplayer.h.

const QgsCoordinateReferenceSystem & QgsMapLayer::crs ( ) const

Returns layer's spatial reference system.

Note: This was introduced in QGIS 1.4

Definition at line 820 of file qgsmaplayer.cpp.

QVariant QgsMapLayer::customProperty	(	const QString &	value,
		const QVariant &	defaultValue = `QVariant()`
	)		const

Read a custom property from layer.

Properties are stored in a map and saved in project file.

Definition at line 1410 of file qgsmaplayer.cpp.

void QgsMapLayer::dataChanged ( )

signal

data of layer changed

const QString& QgsMapLayer::dataUrl ( ) const

inline

Definition at line 104 of file qgsmaplayer.h.

const QString& QgsMapLayer::dataUrlFormat ( ) const

inline

Definition at line 106 of file qgsmaplayer.h.

bool QgsMapLayer::draw ( QgsRenderContext & rendererContext )

virtual

This is the method that does the actual work of drawing the layer onto a paint device.

Parameters

rendererContext describes the extents, resolumon etc. that should be used when rendering the layer.

Reimplemented in QgsVectorLayer, and QgsRasterLayer.

Definition at line 153 of file qgsmaplayer.cpp.

void QgsMapLayer::drawingProgress	(	int	theProgress,
		int	theTotalSteps
	)

signal

Deprecated:: in 2.4 - not emitted anymore

void QgsMapLayer::drawLabels ( QgsRenderContext & rendererContext )

virtual

Draw labels.

Todo:: to be removed: used only in vector layers

Reimplemented in QgsVectorLayer.

Definition at line 159 of file qgsmaplayer.cpp.

virtual QgsError QgsMapLayer::error ( ) const

inlinevirtual

Get current status error.

This error describes some principal problem for which layer cannot work and thus is not valid. It is not last error after accessing data by draw() etc.

Definition at line 250 of file qgsmaplayer.h.

void QgsMapLayer::exportNamedStyle	(	QDomDocument &	doc,
		QString &	errorMsg
	)

virtual

Export the properties of this layer as named style in a QDomDocument.

Parameters

doc	the target QDomDocument
errorMsg	this QString will be initialized on error during the execution of writeSymbology

Definition at line 1060 of file qgsmaplayer.cpp.

void QgsMapLayer::exportSldStyle	(	QDomDocument &	doc,
		QString &	errorMsg
	)

virtual

Export the properties of this layer as SLD style in a QDomDocument.

Parameters

doc	the target QDomDocument
errorMsg	this QString will be initialized on error during the execution of writeSymbology

Definition at line 1237 of file qgsmaplayer.cpp.

QgsRectangle QgsMapLayer::extent ( )

virtual

Return the extent of the layer.

Reimplemented in QgsVectorLayer.

Definition at line 135 of file qgsmaplayer.cpp.

QList< QgsMapLayer * > QgsMapLayer::fromLayerDefinition ( QDomDocument & document )

static

Creates a new layer from a layer defininition document.

Definition at line 633 of file qgsmaplayer.cpp.

QList< QgsMapLayer * > QgsMapLayer::fromLayerDefinitionFile ( const QString & qlrfile )

static

Definition at line 670 of file qgsmaplayer.cpp.

bool QgsMapLayer::hasScaleBasedVisibility ( ) const

Returns whether scale based visibility is enabled for the layer.

Returns: true if scale based visibility is enabled

See Also: minimumScale; maximumScale; setScaleBasedVisibility

Definition at line 771 of file qgsmaplayer.cpp.

QString QgsMapLayer::id ( ) const

Get this layer's unique ID, this ID is used to access this layer from map layer registry.

Get this layer's unique ID.

Definition at line 98 of file qgsmaplayer.cpp.

bool QgsMapLayer::importNamedStyle	(	QDomDocument &	doc,
		QString &	errorMsg
	)

virtual

Import the properties of this layer from a QDomDocument.

Parameters

doc	source QDomDocument
errorMsg	this QString will be initialized on error during the execution of readSymbology

Returns: true on success

Note: added in 2.8

Definition at line 1012 of file qgsmaplayer.cpp.

void QgsMapLayer::invalidTransformInput ( )

virtualslot

Event handler for when a coordinate transform fails due to bad vertex error.

Definition at line 740 of file qgsmaplayer.cpp.

bool QgsMapLayer::isEditable ( ) const

virtual

True if the layer can be edited.

Reimplemented in QgsVectorLayer.

Definition at line 1422 of file qgsmaplayer.cpp.

bool QgsMapLayer::isValid ( )

Return the status of the layer. An invalid layer is one which has a bad datasource or other problem. Child classes set this flag when intialized

Returns: True if the layer is valid and can be accessed

Definition at line 734 of file qgsmaplayer.cpp.

const QString& QgsMapLayer::keywordList ( ) const

inline

Definition at line 100 of file qgsmaplayer.h.

QString QgsMapLayer::lastError ( )

virtual

Deprecated:: since 2.4 - returns empty string

Definition at line 752 of file qgsmaplayer.cpp.

QString QgsMapLayer::lastErrorTitle ( )

virtual

Deprecated:: since 2.4 - returns empty string

Definition at line 747 of file qgsmaplayer.cpp.

void QgsMapLayer::layerCrsChanged ( )

signal

Emit a signal that layer's CRS has been reset.

void QgsMapLayer::layerNameChanged ( )

signal

Emit a signal that the layer name has been changed.

QgsMapLayerLegend * QgsMapLayer::legend ( ) const

Can be null.

Note: added in 2.6

Definition at line 1451 of file qgsmaplayer.cpp.

void QgsMapLayer::legendChanged ( )

signal

Signal emitted when legend of the layer has changed.

Note: added in 2.6

const QString& QgsMapLayer::legendUrl ( ) const

inline

Definition at line 377 of file qgsmaplayer.h.

const QString& QgsMapLayer::legendUrlFormat ( ) const

inline

Definition at line 379 of file qgsmaplayer.h.

QString QgsMapLayer::loadDefaultStyle ( bool & theResultFlag )

virtual

Retrieve the default style for this layer if one exists (either as a .qml file on disk or as a record in the users style table in their personal qgis.db)

Parameters

theResultFlag a reference to a flag that will be set to false if we did not manage to load the default style.

Returns: a QString with any status messages

See Also: also loadNamedStyle ();

Definition at line 906 of file qgsmaplayer.cpp.

QString QgsMapLayer::loadNamedStyle	(	const QString &	theURI,
		bool &	theResultFlag
	)

virtual

Retrieve a named style for this layer if one exists (either as a .qml file on disk or as a record in the users style table in their personal qgis.db)

Parameters

theURI	- the file name or other URI for the style file. First an attempt will be made to see if this is a file and load that, if that fails the qgis.db styles table will be consulted to see if there is a style who's key matches the URI.
theResultFlag	a reference to a flag that will be set to false if we did not manage to load the default style.

Returns: a QString with any status messages

See Also: also loadDefaultStyle ();

Reimplemented in QgsVectorLayer.

Definition at line 956 of file qgsmaplayer.cpp.

bool QgsMapLayer::loadNamedStyleFromDb	(	const QString &	db,
		const QString &	theURI,
		QString &	qml
	)

virtual

Definition at line 911 of file qgsmaplayer.cpp.

QString QgsMapLayer::loadSldStyle	(	const QString &	theURI,
		bool &	theResultFlag
	)

virtual

Definition at line 1337 of file qgsmaplayer.cpp.

float QgsMapLayer::maximumScale ( ) const

Returns the maximum scale denominator at which the layer is visible.

Scale based visibility is only used if hasScaleBasedVisibility is true.

Returns: minimum scale denominator at which the layer will render

See Also: setMaximumScale; minimumScale; hasScaleBasedVisibility

Definition at line 797 of file qgsmaplayer.cpp.

QString QgsMapLayer::metadata ( )

virtualslot

Obtain Metadata for this layer.

Reimplemented in QgsVectorLayer, and QgsRasterLayer.

Definition at line 1471 of file qgsmaplayer.cpp.

const QString& QgsMapLayer::metadataUrl ( ) const

inline

Definition at line 116 of file qgsmaplayer.h.

const QString& QgsMapLayer::metadataUrlFormat ( ) const

inline

Definition at line 120 of file qgsmaplayer.h.

const QString& QgsMapLayer::metadataUrlType ( ) const

inline

Definition at line 118 of file qgsmaplayer.h.

float QgsMapLayer::minimumScale ( ) const

Returns the minimum scale denominator at which the layer is visible.

Scale based visibility is only used if hasScaleBasedVisibility is true.

Returns: minimum scale denominator at which the layer will render

See Also: setMinimumScale; maximumScale; hasScaleBasedVisibility

Definition at line 781 of file qgsmaplayer.cpp.

QString const & QgsMapLayer::name ( ) const

Get the display name of the layer.

Read property of QString layerName.

Returns: the layer name

Definition at line 116 of file qgsmaplayer.cpp.

virtual Q_DECL_DEPRECATED void QgsMapLayer::onCacheImageDelete ( )

inlinevirtual

Deprecated:: since 2.4 - does nothing

Definition at line 386 of file qgsmaplayer.h.

const QString& QgsMapLayer::originalName ( ) const

inline

Get the original name of the layer.

Definition at line 91 of file qgsmaplayer.h.

QString QgsMapLayer::publicSource ( ) const

Gets a version of the internal layer definition that has sensitive bits removed (for example, the password). This function should be used when displaying the source name for general viewing.

Definition at line 122 of file qgsmaplayer.cpp.

void QgsMapLayer::readCustomProperties	(	const QDomNode &	layerNode,
		const QString &	keyStartsWith = `""`
	)

protected

Read custom properties from project file.

Parameters

layerNode	note to read from
keyStartsWith	reads only properties starting with the specified string (or all if the string is empty)

Definition at line 702 of file qgsmaplayer.cpp.

bool QgsMapLayer::readLayerXML ( const QDomElement & layerElement )

sets state from Dom document

Parameters

layerElement The Dom element corresponding to ``maplayer'' tag

Note

The Dom node corresponds to a Dom document project file XML element read by QgsProject.

This, in turn, calls readXml(), which is over-rideable by sub-classes so that they can read their own specific state from the given Dom node.

Invoked by QgsProject::read().

Returns: true if successful

Definition at line 164 of file qgsmaplayer.cpp.

virtual bool QgsMapLayer::readSld	(	const QDomNode &	node,
		QString &	errorMessage
	)

inlinevirtual

Reimplemented in QgsVectorLayer.

Definition at line 353 of file qgsmaplayer.h.

void QgsMapLayer::readStyleManager ( const QDomNode & layerNode )

protected

Read style manager's configuration (if any).

To be called by subclasses.

Definition at line 712 of file qgsmaplayer.cpp.

virtual bool QgsMapLayer::readSymbology	(	const QDomNode &	node,
		QString &	errorMessage
	)

pure virtual

Read the symbology for the current layer from the Dom node supplied.

Parameters

node	node that will contain the symbology definition for this layer.
errorMessage	reference to string that will be updated with any error messages

Returns: true in case of success.

Implemented in QgsVectorLayer, and QgsRasterLayer.

bool QgsMapLayer::readXml ( const QDomNode & layer_node )

protectedvirtual

called by readLayerXML(), used by children to read state specific to them from project files.

Reimplemented in QgsVectorLayer, and QgsRasterLayer.

Definition at line 434 of file qgsmaplayer.cpp.

void QgsMapLayer::recalculateExtents ( )

signal

This is used to send a request that any mapcanvas using this layer update its extents.

virtual void QgsMapLayer::reload ( )

inlinevirtual

Synchronises with changes in the datasource.

Reimplemented in QgsVectorLayer, and QgsRasterLayer.

Definition at line 129 of file qgsmaplayer.h.

void QgsMapLayer::removeCustomProperty ( const QString & key )

Remove a custom property from layer.

Properties are stored in a map and saved in project file.

Definition at line 1415 of file qgsmaplayer.cpp.

void QgsMapLayer::rendererChanged ( )

signal

Signal emitted when renderer is changed.

void QgsMapLayer::repaintRequested ( )

signal

By emitting this signal the layer tells that either appearance or content have been changed and any view showing the rendered layer should refresh itself.

QString QgsMapLayer::saveDefaultStyle ( bool & theResultFlag )

virtual

Save the properties of this layer as the default style (either as a .qml file on disk or as a record in the users style table in their personal qgis.db)

Parameters

theResultFlag a reference to a flag that will be set to false if we did not manage to save the default style.

Returns: a QString with any status messages

See Also: loadNamedStyle() and; saveNamedStyle()

Definition at line 1090 of file qgsmaplayer.cpp.

QString QgsMapLayer::saveNamedStyle	(	const QString &	theURI,
		bool &	theResultFlag
	)

virtual

Save the properties of this layer as a named style (either as a .qml file on disk or as a record in the users style table in their personal qgis.db)

Parameters

theURI	the file name or other URI for the style file. First an attempt will be made to see if this is a file and save to that, if that fails the qgis.db styles table will be used to create a style entry who's key matches the URI.
theResultFlag	a reference to a flag that will be set to false if we did not manage to save the default style.

Returns: a QString with any status messages

See Also: saveDefaultStyle()

Definition at line 1095 of file qgsmaplayer.cpp.

QString QgsMapLayer::saveSldStyle	(	const QString &	theURI,
		bool &	theResultFlag
	)

virtual

Definition at line 1275 of file qgsmaplayer.cpp.

void QgsMapLayer::screenUpdateRequested ( )

signal

Note: Deprecated in 2.4 and not emitted anymore

void QgsMapLayer::setAbstract ( const QString & abstract )

inline

Definition at line 96 of file qgsmaplayer.h.

void QgsMapLayer::setAttribution ( const QString & attrib )

inline

Definition at line 109 of file qgsmaplayer.h.

void QgsMapLayer::setAttributionUrl ( const QString & attribUrl )

inline

Definition at line 111 of file qgsmaplayer.h.

void QgsMapLayer::setBlendMode ( const QPainter::CompositionMode & blendMode )

Write blend mode for layer.

Definition at line 141 of file qgsmaplayer.cpp.

void QgsMapLayer::setCacheImage ( QImage * )

Deprecated:: since 2.4 - caches listen to repaintRequested() signal to invalidate the cached image

Definition at line 1432 of file qgsmaplayer.cpp.

void QgsMapLayer::setCrs	(	const QgsCoordinateReferenceSystem &	srs,
		bool	emitSignal = `true`
	)

Sets layer's spatial reference system.

Definition at line 825 of file qgsmaplayer.cpp.

void QgsMapLayer::setCustomProperty	(	const QString &	key,
		const QVariant &	value
	)

Set a custom property for layer.

Properties are stored in a map and saved in project file.

Definition at line 1405 of file qgsmaplayer.cpp.

void QgsMapLayer::setDataUrl ( const QString & dataUrl )

inline

Definition at line 103 of file qgsmaplayer.h.

void QgsMapLayer::setDataUrlFormat ( const QString & dataUrlFormat )

inline

Definition at line 105 of file qgsmaplayer.h.

void QgsMapLayer::setError ( const QgsError & theError )

inlineprotected

Set error message.

Definition at line 565 of file qgsmaplayer.h.

void QgsMapLayer::setExtent ( const QgsRectangle & rect )

protectedvirtual

Set the extent.

Reimplemented in QgsVectorLayer, and QgsPluginLayer.

Definition at line 1476 of file qgsmaplayer.cpp.

void QgsMapLayer::setKeywordList ( const QString & keywords )

inline

Definition at line 99 of file qgsmaplayer.h.

void QgsMapLayer::setLayerName ( const QString & name )

Set the display name of the layer.

Write property of QString layerName.

Parameters

name	New name for the layer

Definition at line 104 of file qgsmaplayer.cpp.

void QgsMapLayer::setLayerOrder ( const QStringList & layers )

virtual

Reorders the previously selected sublayers of this layer from bottom to top (Useful for providers that manage their own layers, such as WMS)

Reimplemented in QgsRasterLayer.

Definition at line 807 of file qgsmaplayer.cpp.

void QgsMapLayer::setLegend ( QgsMapLayerLegend * legend )

Assign a legend controller to the map layer.

The object will be responsible for providing legend items.

Parameters

legend Takes ownership of the object. Can be null pointer

Note: added in 2.6

Definition at line 1437 of file qgsmaplayer.cpp.

void QgsMapLayer::setLegendUrl ( const QString & legendUrl )

inline

Definition at line 376 of file qgsmaplayer.h.

void QgsMapLayer::setLegendUrlFormat ( const QString & legendUrlFormat )

inline

Definition at line 378 of file qgsmaplayer.h.

void QgsMapLayer::setMaximumScale ( const float theMaxScale )

slot

Sets the maximum scale denominator at which the layer will be visible.

Scale based visibility is only used if setScaleBasedVisibility is set to true.

Parameters

theMaxScale maximum scale denominator at which the layer should render

See Also: maximumScale; setMinimumScale; setScaleBasedVisibility

Definition at line 787 of file qgsmaplayer.cpp.

void QgsMapLayer::setMetadataUrl ( const QString & metaUrl )

inline

Definition at line 115 of file qgsmaplayer.h.

void QgsMapLayer::setMetadataUrlFormat ( const QString & metaUrlFormat )

inline

Definition at line 119 of file qgsmaplayer.h.

void QgsMapLayer::setMetadataUrlType ( const QString & metaUrlType )

inline

Definition at line 117 of file qgsmaplayer.h.

void QgsMapLayer::setMinimumScale ( const float theMinScale )

slot

Sets the minimum scale denominator at which the layer will be visible.

Scale based visibility is only used if setScaleBasedVisibility is set to true.

Parameters

theMinScale minimum scale denominator at which the layer should render

See Also: minimumScale; setMaximumScale; setScaleBasedVisibility

Definition at line 776 of file qgsmaplayer.cpp.

void QgsMapLayer::setScaleBasedVisibility ( const bool enabled )

slot

Sets whether scale based visibility is enabled for the layer.

Parameters

enabled set to true to enable scale based visibility

See Also: setMinimumScale; setMaximumScale; scaleBasedVisibility

Definition at line 792 of file qgsmaplayer.cpp.

void QgsMapLayer::setSubLayerVisibility	(	QString	name,
		bool	vis
	)

virtual

Set the visibility of the given sublayer name.

Reimplemented in QgsRasterLayer.

Definition at line 813 of file qgsmaplayer.cpp.

void QgsMapLayer::setTitle ( const QString & title )

inline

Definition at line 93 of file qgsmaplayer.h.

void QgsMapLayer::setValid ( bool valid )

protected

set whether layer is valid or not - should be used in constructor.

Definition at line 1427 of file qgsmaplayer.cpp.

QString const & QgsMapLayer::source ( ) const

Returns the source for the layer.

Definition at line 130 of file qgsmaplayer.cpp.

void QgsMapLayer::statusChanged ( QString theStatus )

signal

Emit a signal with status (e.g.

to be caught by QgisApp and display a msg on status bar)

QgsMapLayerStyleManager * QgsMapLayer::styleManager ( ) const

Get access to the layer's style manager.

Style manager allows switching between multiple styles.

Note: added in 2.8

Definition at line 1456 of file qgsmaplayer.cpp.

QString QgsMapLayer::styleURI ( )

virtual

Retrieve the style URI for this layer (either as a .qml file on disk or as a record in the users style table in their personal qgis.db)

Returns: a QString with the style file name

See Also: also loadNamedStyle () and saveNamedStyle ();

Definition at line 854 of file qgsmaplayer.cpp.

QStringList QgsMapLayer::subLayers ( ) const

virtual

Returns the sublayers of this layer (Useful for providers that manage their own layers, such as WMS)

Reimplemented in QgsRasterLayer.

Definition at line 802 of file qgsmaplayer.cpp.

virtual QDateTime QgsMapLayer::timestamp ( ) const

inlinevirtualslot

Time stamp of data source in the moment when data/metadata were loaded by provider.

Reimplemented in QgsRasterLayer.

Definition at line 484 of file qgsmaplayer.h.

const QString& QgsMapLayer::title ( ) const

inline

Definition at line 94 of file qgsmaplayer.h.

void QgsMapLayer::toggleScaleBasedVisibility ( bool theVisibilityFlag )

slot

Accessor for the scale based visilibility flag.

Deprecated:: use setScaleBasedVisibility instead

Definition at line 766 of file qgsmaplayer.cpp.

void QgsMapLayer::triggerRepaint ( )

slot

Will advice the map canvas (and any other interested party) that this layer requires to be repainted.

Will emit a repaintRequested() signal.

Note: in 2.6 function moved from vector/raster subclasses to QgsMapLayer

Definition at line 1466 of file qgsmaplayer.cpp.

QgsMapLayer::LayerType QgsMapLayer::type ( ) const

Get the type of the layer.

Returns: Integer matching a value in the QgsMapLayer::LayerType enum

Definition at line 92 of file qgsmaplayer.cpp.

QUndoStack * QgsMapLayer::undoStack ( )

Return pointer to layer's undo stack.

Definition at line 1399 of file qgsmaplayer.cpp.

void QgsMapLayer::writeCustomProperties	(	QDomNode &	layerNode,
		QDomDocument &	doc
	)		const

protected

Write custom properties to project file.

Definition at line 707 of file qgsmaplayer.cpp.

bool QgsMapLayer::writeLayerXML	(	QDomElement &	layerElement,
		QDomDocument &	document,
		QString	relativeBasePath = `QString::null`
	)

stores state in Dom node

Parameters

layerElement	is a Dom element corresponding to ``maplayer'' tag
document	is a the dom document being written
relativeBasePath	base path for relative paths

Note

The Dom node corresponds to a Dom document project file XML element to be written by QgsProject.

This, in turn, calls writeXml(), which is over-rideable by sub-classes so that they can write their own specific state to the given Dom node.

Invoked by QgsProject::write().

Returns: true if successful

Definition at line 444 of file qgsmaplayer.cpp.

void QgsMapLayer::writeStyleManager	(	QDomNode &	layerNode,
		QDomDocument &	doc
	)		const

protected

Write style manager's configuration (if exists).

To be called by subclasses.

Definition at line 721 of file qgsmaplayer.cpp.

virtual bool QgsMapLayer::writeSymbology	(	QDomNode &	node,
		QDomDocument &	doc,
		QString &	errorMessage
	)		const

pure virtual

Write the symbology for the layer into the docment provided.

Parameters

node	the node that will have the style element added to it.
doc	the document that will have the QDomNode added.
errorMessage	reference to string that will be updated with any error messages

Returns: true in case of success.

Implemented in QgsVectorLayer, and QgsRasterLayer.

bool QgsMapLayer::writeXml	(	QDomNode &	layer_node,
		QDomDocument &	document
	)

protectedvirtual

called by writeLayerXML(), used by children to write state specific to them to project files.

Reimplemented in QgsVectorLayer, and QgsRasterLayer.

Definition at line 692 of file qgsmaplayer.cpp.

Member Data Documentation

QString QgsMapLayer::mAbstract

protected

Description of the layer.

Definition at line 586 of file qgsmaplayer.h.

QString QgsMapLayer::mAttribution

protected

Attribution of the layer.

Definition at line 594 of file qgsmaplayer.h.

QString QgsMapLayer::mAttributionUrl

protected

Definition at line 595 of file qgsmaplayer.h.

QString QgsMapLayer::mDataSource

protected

data source description string, varies by layer type

Definition at line 574 of file qgsmaplayer.h.

QString QgsMapLayer::mDataUrl

protected

DataUrl of the layer.

Definition at line 590 of file qgsmaplayer.h.

QString QgsMapLayer::mDataUrlFormat

protected

Definition at line 591 of file qgsmaplayer.h.

QgsError QgsMapLayer::mError

protected

Error.

Definition at line 607 of file qgsmaplayer.h.

QgsRectangle QgsMapLayer::mExtent

protected

Extent of the layer.

Definition at line 568 of file qgsmaplayer.h.

QString QgsMapLayer::mKeywordList

protected

Definition at line 587 of file qgsmaplayer.h.

QString QgsMapLayer::mLayerName

protected

Name of the layer - used for display.

Definition at line 577 of file qgsmaplayer.h.

QString QgsMapLayer::mLayerOrigName

protected

Original name of the layer.

Definition at line 581 of file qgsmaplayer.h.

QString QgsMapLayer::mLegendUrl

protected

WMS legend.

Definition at line 603 of file qgsmaplayer.h.

QString QgsMapLayer::mLegendUrlFormat

protected

Definition at line 604 of file qgsmaplayer.h.

QString QgsMapLayer::mMetadataUrl

protected

MetadataUrl of the layer.

Definition at line 598 of file qgsmaplayer.h.

QString QgsMapLayer::mMetadataUrlFormat

protected

Definition at line 600 of file qgsmaplayer.h.

QString QgsMapLayer::mMetadataUrlType

protected

Definition at line 599 of file qgsmaplayer.h.

QString QgsMapLayer::mTitle

protected

Definition at line 583 of file qgsmaplayer.h.

bool QgsMapLayer::mValid

protected

Indicates if the layer is valid and can be drawn.

Definition at line 571 of file qgsmaplayer.h.

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

/tmp/buildd/qgis-2.8.2+12wheezy/src/core/qgsmaplayer.h
/tmp/buildd/qgis-2.8.2+12wheezy/src/core/qgsmaplayer.cpp

Public Types

Public Slots

Signals

Public Member Functions

Static Public Member Functions

Protected Member Functions

Protected Attributes

Detailed Description

Member Enumeration Documentation

Constructor & Destructor Documentation

Member Function Documentation

Member Data Documentation