QGIS/python/core/qgsvectorlayer.sip

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typedef QList<int> QgsAttributeList;
typedef QSet<int> QgsAttributeIds;
/** \ingroup core
* Represents a vector layer which manages a vector based data sets.
*
* The QgsVectorLayer is instantiated by specifying the name of a data provider,
* such as postgres or wfs, and url defining the specific data set to connect to.
* The vector layer constructor in turn instantiates a QgsVectorDataProvider subclass
* corresponding to the provider type, and passes it the url. The data provider
* connects to the data source.
*
* The QgsVectorLayer provides a common interface to the different data types. It also
* manages editing transactions.
*
* Sample usage of the QgsVectorLayer class:
*
* \code
* QString uri = "point?crs=epsg:4326&field=id:integer";
* QgsVectorLayer *scratchLayer = new QgsVectorLayer(uri, "Scratch point layer", "memory");
* \endcode
*
* The main data providers supported by QGIS are listed below.
*
* \section providers Vector data providers
*
* \subsection memory Memory data providerType (memory)
*
* The memory data provider is used to construct in memory data, for example scratch
* data or data generated from spatial operations such as contouring. There is no
* inherent persistent storage of the data. The data source uri is constructed. The
* url specifies the geometry type ("point", "linestring", "polygon",
* "multipoint","multilinestring","multipolygon"), optionally followed by url parameters
* as follows:
*
* - crs=definition
* Defines the coordinate reference system to use for the layer.
* definition is any string accepted by QgsCoordinateReferenceSystem::createFromString()
*
* - index=yes
* Specifies that the layer will be constructed with a spatial index
*
* - field=name:type(length,precision)
* Defines an attribute of the layer. Multiple field parameters can be added
* to the data provider definition. type is one of "integer", "double", "string".
*
* An example url is "Point?crs=epsg:4326&field=id:integer&field=name:string(20)&index=yes"
*
* \subsection ogr OGR data provider (ogr)
*
* Accesses data using the OGR drivers (http://www.gdal.org/ogr/ogr_formats.html). The url
* is the OGR connection string. A wide variety of data formats can be accessed using this
* driver, including file based formats used by many GIS systems, database formats, and
* web services. Some of these formats are also supported by custom data providers listed
* below.
*
* \subsection spatialite Spatialite data provider (spatialite)
*
* Access data in a spatialite database. The url defines the connection parameters, table,
* geometry column, and other attributes. The url can be constructed using the
* QgsDataSourceUri class.
*
* \subsection postgres Postgresql data provider (postgres)
*
* Connects to a postgresql database. The url defines the connection parameters, table,
* geometry column, and other attributes. The url can be constructed using the
* QgsDataSourceUri class.
*
* \subsection mssql Microsoft SQL server data provider (mssql)
*
* Connects to a Microsoft SQL server database. The url defines the connection parameters, table,
* geometry column, and other attributes. The url can be constructed using the
* QgsDataSourceUri class.
*
* \subsection wfs WFS (web feature service) data provider (wfs)
*
* Used to access data provided by a web feature service.
*
* The url can be a HTTP url to a WFS server (legacy, e.g. http://foobar/wfs?TYPENAME=xxx&SRSNAME=yyy[&FILTER=zzz]), or,
* starting with QGIS 2.16, a URI constructed using the QgsDataSourceUri class with the following parameters :
* - url=string (mandatory): HTTP url to a WFS server endpoint. e.g http://foobar/wfs
* - typename=string (mandatory): WFS typename
* - srsname=string (recommended): SRS like 'EPSG:XXXX'
* - username=string
* - password=string
* - authcfg=string
* - version=auto/1.0.0/1.1.0/2.0.0
* -sql=string: full SELECT SQL statement with optional WHERE, ORDER BY and possibly with JOIN if supported on server
* - filter=string: QGIS expression or OGC/FES filter
* - retrictToRequestBBOX=1: to download only features in the view extent (or more generally
* in the bounding box of the feature iterator)
* - maxNumFeatures=number
* - IgnoreAxisOrientation=1: to ignore EPSG axis order for WFS 1.1 or 2.0
* - InvertAxisOrientation=1: to invert axis order
* - hideDownloadProgressDialog=1: to hide the download progress dialog
*
* The FILTER query string parameter can be used to filter
* the WFS feature type. The FILTER key value can either be a QGIS expression
* or an OGC XML filter. If the value is set to a QGIS expression the driver will
* turn it into OGC XML filter before passing it to the WFS server. Beware the
* QGIS expression filter only supports” =, !=, <, >, <=, >=, AND, OR, NOT, LIKE, IS NULL”
* attribute operators, “BBOX, Disjoint, Intersects, Touches, Crosses, Contains, Overlaps, Within”
* spatial binary operators and the QGIS local “geomFromWKT, geomFromGML”
* geometry constructor functions.
*
* Also note:
*
* - You can use various functions available in the QGIS Expression list,
* however the function must exist server side and have the same name and arguments to work.
*
* - Use the special $geometry parameter to provide the layer geometry column as input
* into the spatial binary operators e.g intersects($geometry, geomFromWKT('POINT (5 6)'))
*
* \subsection delimitedtext Delimited text file data provider (delimitedtext)
*
* Accesses data in a delimited text file, for example CSV files generated by
* spreadsheets. The contents of the file are split into columns based on specified
* delimiter characters. Each record may be represented spatially either by an
* X and Y coordinate column, or by a WKT (well known text) formatted columns.
*
* The url defines the filename, the formatting options (how the
* text in the file is divided into data fields, and which fields contain the
* X,Y coordinates or WKT text definition. The options are specified as url query
* items.
*
* At its simplest the url can just be the filename, in which case it will be loaded
* as a CSV formatted file.
*
* The url may include the following items:
*
* - encoding=UTF-8
*
* Defines the character encoding in the file. The default is UTF-8. To use
* the default encoding for the operating system use "System".
*
* - type=(csv|regexp|whitespace|plain)
*
* Defines the algorithm used to split records into columns. Records are
* defined by new lines, except for csv format files for which quoted fields
* may span multiple records. The default type is csv.
*
* - "csv" splits the file based on three sets of characters:
* delimiter characters, quote characters,
* and escape characters. Delimiter characters mark the end
* of a field. Quote characters enclose a field which can contain
* delimiter characters, and newlines. Escape characters cause the
* following character to be treated literally (including delimiter,
* quote, and newline characters). Escape and quote characters must
* be different from delimiter characters. Escape characters that are
* also quote characters are treated specially - they can only
* escape themselves within quotes. Elsewhere they are treated as
* quote characters. The defaults for delimiter, quote, and escape
* are ',', '"', '"'.
* - "regexp" splits each record using a regular expression (see QRegExp
* documentation for details).
* - "whitespace" splits each record based on whitespace (on or more whitespace
* characters. Leading whitespace in the record is ignored.
* - "plain" is provided for backwards compatibility. It is equivalent to
* CSV except that the default quote characters are single and double quotes,
* and there is no escape characters.
*
* - delimiter=characters
*
* Defines the delimiter characters used for csv and plain type files, or the
* regular expression for regexp type files. It is a literal string of characters
* except that "\t" may be used to represent a tab character.
*
* - quote=characters
*
* Defines the characters that are used as quote characters for csv and plain type
* files.
*
* - escape=characters
*
* Defines the characters used to escape delimiter, quote, and newline characters.
*
* - skipLines=n
*
* Defines the number of lines to ignore at the beginning of the file (default 0)
*
* - useHeader=(yes|no)
*
* Defines whether the first record in the file (after skipped lines) contains
* column names (default yes)
*
* - trimFields=(yes|no)
*
* If yes then leading and trailing whitespace will be removed from fields
*
* - skipEmptyFields=(yes|no)
*
* If yes then empty fields will be discarded (equivalent to concatenating consecutive
* delimiters)
*
* - maxFields=#
*
* Specifies the maximum number of fields to load for each record. Additional
* fields will be discarded. Default is 0 - load all fields.
*
* - decimalPoint=c
*
* Defines a character that is used as a decimal point in the numeric columns
* The default is '.'.
*
* - xField=column yField=column
*
* Defines the name of the columns holding the x and y coordinates for XY point geometries.
* If the useHeader is no (ie there are no column names), then this is the column
* number (with the first column as 1).
*
* - xyDms=(yes|no)
*
* If yes then the X and Y coordinates are interpreted as
* degrees/minutes/seconds format (fairly permissively),
* or degree/minutes format.
*
* - wktField=column
*
* Defines the name of the columns holding the WKT geometry definition for WKT geometries.
* If the useHeader is no (ie there are no column names), then this is the column
* number (with the first column as 1).
*
* - geomType=(point|line|polygon|none)
*
* Defines the geometry type for WKT type geometries. QGIS will only display one
* type of geometry for the layer - any others will be ignored when the file is
* loaded. By default the provider uses the type of the first geometry in the file.
* Use geomType to override this type.
*
* geomType can also be set to none, in which case the layer is loaded without
* geometries.
*
* - subset=expression
*
* Defines an expression that will identify a subset of records to display
*
* - crs=crsstring
*
* Defines the coordinate reference system used for the layer. This can be
* any string accepted by QgsCoordinateReferenceSystem::createFromString()
*
* -subsetIndex=(yes|no)
*
* Determines whether the provider generates an index to improve the efficiency
* of subsets. The default is yes
*
* -spatialIndex=(yes|no)
*
* Determines whether the provider generates a spatial index. The default is no.
*
* -watchFile=(yes|no)
*
* Defines whether the file will be monitored for changes. The default is
* to monitor for changes.
*
* - quiet
*
* Errors encountered loading the file will not be reported in a user dialog if
* quiet is included (They will still be shown in the output log).
*
* \subsection gpx GPX data provider (gpx)
*
* Provider reads tracks, routes, and waypoints from a GPX file. The url
* defines the name of the file, and the type of data to retrieve from it
* ("track", "route", or "waypoint").
*
* An example url is "/home/user/data/holiday.gpx?type=route"
*
* \subsection grass Grass data provider (grass)
*
* Provider to display vector data in a GRASS GIS layer.
*
* TODO QGIS3: Remove virtual from non-inherited methods (like isModified)
*/
class QgsVectorLayer : QgsMapLayer, QgsExpressionContextGenerator
{
%TypeHeaderCode
#include "qgsvectorlayer.h"
%End
public:
//! Result of an edit operation
enum EditResult
{
Success, /**< Edit operation was successful */
EmptyGeometry, /**< Edit operation resulted in an empty geometry */
EditFailed, /**< Edit operation failed */
FetchFeatureFailed, /**< Unable to fetch requested feature */
InvalidLayer, /**< Edit failed due to invalid layer */
};
//! Selection behavior
enum SelectBehavior
{
SetSelection, /**< Set selection, removing any existing selection */
AddToSelection, /**< Add selection to current selection */
IntersectSelection, /**< Modify current selection to include only select features which match */
RemoveFromSelection, /**< Remove from current selection */
};
/** Constructor - creates a vector layer
*
* The QgsVectorLayer is constructed by instantiating a data provider. The provider
* interprets the supplied path (url) of the data source to connect to and access the
* data.
*
* @param path The path or url of the parameter. Typically this encodes
* parameters used by the data provider as url query items.
* @param baseName The name used to represent the layer in the legend
* @param providerLib The name of the data provider, e.g., "memory", "postgres"
* @param loadDefaultStyleFlag whether to load the default style
*
*/
QgsVectorLayer( const QString& path = QString::null, const QString& baseName = QString::null,
const QString& providerLib = "ogr", bool loadDefaultStyleFlag = true );
/** Destructor */
virtual ~QgsVectorLayer();
/** Returns the permanent storage type for this layer as a friendly name. */
QString storageType() const;
/** Capabilities for this layer in a friendly format. */
QString capabilitiesString() const;
/** Returns a comment for the data in the layer */
QString dataComment() const;
/**
* This is a shorthand for accessing the displayExpression if it is a simple field.
* If the displayExpression is more complex than a simple field, a null string will
* be returned.
*
* @see displayExpression
*/
QString displayField() const;
/** Set the preview expression, used to create a human readable preview string.
* Used e.g. in the attribute table feature list. Uses { @link QgsExpression }.
*
* @param displayExpression The expression which will be used to preview features
* for this layer
*/
void setDisplayExpression( const QString& displayExpression );
/**
* Get the preview expression, used to create a human readable preview string.
* Uses { @link QgsExpression }
*
* @return The expression which will be used to preview features for this layer
*/
QString displayExpression() const;
/** Returns the data provider */
QgsVectorDataProvider* dataProvider();
/** Returns the data provider in a const-correct manner
* @note not available in python bindings
*/
// const QgsVectorDataProvider* dataProvider() const;
/** Sets the textencoding of the data provider */
void setProviderEncoding( const QString& encoding );
/** Setup the coordinate system transformation for the layer */
void setCoordinateSystem();
/** Joins another vector layer to this layer
@param joinInfo join object containing join layer id, target and source field
@note since 2.6 returns bool indicating whether the join can be added */
bool addJoin( const QgsVectorLayerJoinInfo& joinInfo );
/** Removes a vector layer join
@returns true if join was found and successfully removed */
bool removeJoin( const QString& joinLayerId );
/**
* Accessor to the join buffer object
* @note added 2.14.7
*/
QgsVectorLayerJoinBuffer* joinBuffer();
const QList<QgsVectorLayerJoinInfo> vectorJoins() const;
/**
* Sets the list of dependencies.
* @see dependencies()
*
* @param layers set of QgsMapLayerDependency. Only user-defined dependencies will be added
* @returns false if a dependency cycle has been detected
* @note added in QGIS 3.0
*/
virtual bool setDependencies( const QSet<QgsMapLayerDependency>& layers );
/**
* Gets the list of dependencies. This includes data dependencies set by the user (@see setDataDependencies)
* as well as dependencies given by the provider
*
* @returns a set of QgsMapLayerDependency
* @note added in QGIS 3.0
*/
virtual QSet<QgsMapLayerDependency> dependencies() const;
/**
* Add a new field which is calculated by the expression specified
*
* @param exp The expression which calculates the field
* @param fld The field to calculate
*
* @return The index of the new field
*
* @note added in 2.6, return value added in 2.9
*/
int addExpressionField( const QString& exp, const QgsField& fld );
/**
* Remove an expression field
*
* @param index The index of the field
*
* @note added in 2.6
*/
void removeExpressionField( int index );
/**
* Returns the expression used for a given expression field
*
* @param index An index of an epxression based (virtual) field
*
* @return The expression for the field at index
*
* @note added in 2.9
*/
QString expressionField( int index ) const;
/**
* Changes the expression used to define an expression based (virtual) field
*
* @param index The index of the expression to change
*
* @param exp The new expression to set
*
* @note added in 2.9
*/
void updateExpressionField( int index, const QString& exp );
/**
* Get all layer actions defined on this layer.
*
* The pointer which is returned directly points to the actions object
* which is used by the layer, so any changes are immediately applied.
*/
QgsActionManager* actions();
/**
* The number of features that are selected in this layer
*
* @return See description
*/
int selectedFeatureCount() const;
/**
* Select features found within the search rectangle (in layer's coordinates)
* @param rect search rectangle
* @param behavior selection type, allows adding to current selection, removing
* from selection, etc.
* @see invertSelectionInRectangle(QgsRectangle & rect)
* @see selectByExpression()
* @see selectByIds()
*/
void selectByRect( QgsRectangle & rect, SelectBehavior behavior = SetSelection );
/** Select matching features using an expression.
* @param expression expression to evaluate to select features
* @param behavior selection type, allows adding to current selection, removing
* from selection, etc.
* @note added in QGIS 2.16
* @see selectByRect()
* @see selectByIds()
*/
void selectByExpression( const QString& expression, SelectBehavior behavior = SetSelection );
/** Select matching features using a list of feature IDs. Will emit the
* selectionChanged() signal with the clearAndSelect flag set.
* @param ids feature IDs to select
* @param behavior selection type, allows adding to current selection, removing
* from selection, etc.
* @note added in QGIS 2.16
* @see selectByRect()
* @see selectByExpression()
*/
void selectByIds( const QgsFeatureIds &ids, SelectBehavior behavior = SetSelection );
/**
* Modifies the current selection on this layer
*
* @param selectIds Select these ids
* @param deselectIds Deselect these ids
*
* @see select(QgsFeatureIds)
* @see select(QgsFeatureId)
* @see deselect(QgsFeatureIds)
* @see deselect(QgsFeatureId)
* @see selectByExpression()
*/
void modifySelection( const QgsFeatureIds& selectIds, const QgsFeatureIds& deselectIds );
/** Select not selected features and deselect selected ones */
void invertSelection();
/** Select all the features */
void selectAll();
/** Get all feature Ids */
QgsFeatureIds allFeatureIds() const;
/**
* Invert selection of features found within the search rectangle (in layer's coordinates)
*
* @param rect The rectangle in which the selection of features will be inverted
*
* @see invertSelection()
*/
void invertSelectionInRectangle( QgsRectangle & rect );
/**
* Get a copy of the user-selected features
*
* @return A list of { @link QgsFeature } 's
*
* @see selectedFeatureIds()
* @see selectedFeaturesIterator() which is more memory friendly when handling large selections
*/
QgsFeatureList selectedFeatures() const;
/**
* Get an iterator of the selected features
*
* @param request You may specify a request, e.g. to limit the set of requested attributes.
* Any filter on the request will be discarded.
*
* @return Iterator over the selected features
*
* @see selectedFeatureIds()
* @see selectedFeatures()
*/
QgsFeatureIterator selectedFeaturesIterator( QgsFeatureRequest request = QgsFeatureRequest() ) const;
/**
* Return reference to identifiers of selected features
*
* @return A list of { @link QgsFeatureId } 's
* @see selectedFeatures()
*/
const QgsFeatureIds &selectedFeatureIds() const;
/** Returns the bounding box of the selected features. If there is no selection, QgsRectangle(0,0,0,0) is returned */
QgsRectangle boundingBoxOfSelected() const;
/** Returns whether the layer contains labels which are enabled and should be drawn.
* @return true if layer contains enabled labels
* @note added in QGIS 2.9
*/
bool labelsEnabled() const;
/** Returns whether the layer contains diagrams which are enabled and should be drawn.
* @return true if layer contains enabled diagrams
* @note added in QGIS 2.9
*/
bool diagramsEnabled() const;
/** Sets diagram rendering object (takes ownership) */
void setDiagramRenderer( QgsDiagramRenderer* r /Transfer/ );
const QgsDiagramRenderer* diagramRenderer() const;
void setDiagramLayerSettings( const QgsDiagramLayerSettings& s );
const QgsDiagramLayerSettings *diagramLayerSettings() const;
/** Return renderer. */
QgsFeatureRenderer* renderer();
/** Return const renderer.
* @note not available in python bindings
*/
// const QgsFeatureRenderer* renderer() const { return mRendererV2; }
/**
* Set renderer which will be invoked to represent this layer.
* Ownership is transferred.
*/
void setRenderer( QgsFeatureRenderer* r /Transfer/ );
/** Returns point, line or polygon */
QgsWkbTypes::GeometryType geometryType() const;
/** Returns true if this is a geometry layer and false in case of NoGeometry (table only) or UnknownGeometry */
bool hasGeometryType() const;
/** Returns the WKBType or WKBUnknown in case of error*/
QgsWkbTypes::Type wkbType() const;
/** Return the provider type for this layer */
QString providerType() const;
/** Reads vector layer specific state from project file Dom node.
* @note Called by QgsMapLayer::readXml().
*/
virtual bool readXml( const QDomNode& layer_node );
/** Write vector layer specific state to project file Dom node.
* @note Called by QgsMapLayer::writeXml().
*/
virtual bool writeXml( QDomNode & layer_node, QDomDocument & doc ) const;
/** Resolve references to other layers (kept as layer IDs after reading XML) into layer objects.
* @note added in 3.0
*/
void resolveReferences( QgsProject* project );
/**
* Save named and sld style of the layer to the style table in the db.
* @param name
* @param description
* @param useAsDefault
* @param uiFileContent
* @param msgError (out)
*/
virtual void saveStyleToDatabase( const QString& name, const QString& description,
bool useAsDefault, const QString& uiFileContent,
QString &msgError /Out/ );
/**
* Lists all the style in db split into related to the layer and not related to
* @param ids the list in which will be stored the style db ids
* @param names the list in which will be stored the style names
* @param descriptions the list in which will be stored the style descriptions
* @param msgError
* @return the number of styles related to current layer
*/
virtual int listStylesInDatabase( QStringList &ids /Out/, QStringList &names /Out/,
QStringList &descriptions /Out/, QString &msgError /Out/ );
/**
* Will return the named style corresponding to style id provided
*/
virtual QString getStyleFromDatabase( const QString& styleId, QString &msgError /Out/ );
/**
* Delete a style from the database
* @note added in QGIS 3.0
* @param styleId the provider's layer_styles table id of the style to delete
* @param msgError reference to string that will be updated with any error messages
* @return true in case of success
*/
virtual bool deleteStyleFromDatabase( const QString& styleId, QString &msgError /Out/ );
/**
* Load a named style from file/local db/datasource db
* @param theURI the URI of the style or the URI of the layer
* @param resultFlag will be set to true if a named style is correctly loaded
* @param loadFromLocalDb if true forces to load from local db instead of datasource one
*/
virtual QString loadNamedStyle( const QString &theURI, bool &resultFlag /Out/, bool loadFromLocalDb );
/**
* Calls loadNamedStyle( theURI, resultFlag, false );
* Retained for backward compatibility
*/
virtual QString loadNamedStyle( const QString &theURI, bool &resultFlag /Out/ );
/** Read the symbology for the current layer from the Dom node supplied.
* @param node node that will contain the symbology definition for this layer.
* @param errorMessage reference to string that will be updated with any error messages
* @return true in case of success.
*/
bool readSymbology( const QDomNode& node, QString& errorMessage );
/** Read the style for the current layer from the Dom node supplied.
* @param node node that will contain the style definition for this layer.
* @param errorMessage reference to string that will be updated with any error messages
* @return true in case of success.
*/
bool readStyle( const QDomNode& node, QString& errorMessage );
/** Write the symbology for the layer into the docment provided.
* @param node the node that will have the style element added to it.
* @param doc the document that will have the QDomNode added.
* @param errorMessage reference to string that will be updated with any error messages
* @return true in case of success.
*/
bool writeSymbology( QDomNode& node, QDomDocument& doc, QString& errorMessage ) const;
/** Write just the style information for the layer into the document
* @param node the node that will have the style element added to it.
* @param doc the document that will have the QDomNode added.
* @param errorMessage reference to string that will be updated with any error messages
* @return true in case of success.
*/
bool writeStyle( QDomNode& node, QDomDocument& doc, QString& errorMessage ) const;
bool writeSld( QDomNode& node, QDomDocument& doc, QString& errorMessage, const QgsStringMap& props ) const;
bool readSld( const QDomNode& node, QString& errorMessage );
/**
* Number of features rendered with specified legend key. Features must be first
* calculated by countSymbolFeatures()
* @return number of features rendered by symbol or -1 if failed or counts are not available
*/
long featureCount( const QString& legendKey ) const;
/**
* Update the data source of the layer. The layer's renderer and legend will be preserved only
* if the geometry type of the new data source matches the current geometry type of the layer.
* @param dataSource new layer data source
* @param baseName base name of the layer
* @param provider provider string
* @param loadDefaultStyleFlag set to true to reset the layer's style to the default for the
* data source
* @note added in QGIS 2.10
*/
void setDataSource( const QString& dataSource, const QString& baseName, const QString& provider, bool loadDefaultStyleFlag = false );
/**
* Count features for symbols. Feature counts may be get by featureCount().
* @param showProgress show progress dialog
* @return true if calculated, false if failed or was canceled by user
*/
bool countSymbolFeatures( bool showProgress = true );
/**
* Set the string (typically sql) used to define a subset of the layer
* @param subset The subset string. This may be the where clause of a sql statement
* or other definition string specific to the underlying dataprovider
* and data store.
* @return true, when setting the subset string was successful, false otherwise
*/
virtual bool setSubsetString( const QString& subset );
/**
* Get the string (typically sql) used to define a subset of the layer
* @return The subset string or QString::null if not implemented by the provider
*/
virtual QString subsetString() const;
/**
* Query the layer for features specified in request.
* @param request feature request describing parameters of features to return
* @returns iterator for matching features from provider
*/
QgsFeatureIterator getFeatures( const QgsFeatureRequest& request = QgsFeatureRequest() ) const;
/**
* Query the layer for features matching a given expression.
*/
QgsFeatureIterator getFeatures( const QString& expression );
/**
* Query the layer for the feature with the given id.
* If there is no such feature, the returned feature will be invalid.
*/
QgsFeature getFeature( QgsFeatureId fid );
/**
* Query the layer for the features with the given ids.
*/
QgsFeatureIterator getFeatures( QgsFeatureIds fids );
/**
* Query the layer for the features which intersect the specified rectangle.
*/
QgsFeatureIterator getFeatures( const QgsRectangle& rectangle );
/** Adds a feature
@param feature feature to add
@param alsoUpdateExtent If True, will also go to the effort of e.g. updating the extents.
@return True in case of success and False in case of error
*/
bool addFeature( QgsFeature& feature, bool alsoUpdateExtent = true );
/** Updates an existing feature. This method needs to query the datasource
on every call. Consider using {@link changeAttributeValue()} or
{@link changeGeometry()} instead.
@param f Feature to update
@return True in case of success and False in case of error
*/
bool updateFeature( QgsFeature &f );
/** Insert a new vertex before the given vertex number,
* in the given ring, item (first number is index 0), and feature
* Not meaningful for Point geometries
*/
bool insertVertex( double x, double y, QgsFeatureId atFeatureId, int beforeVertex );
/** Insert a new vertex before the given vertex number,
* in the given ring, item (first number is index 0), and feature
* Not meaningful for Point geometries
*/
bool insertVertex( const QgsPointV2& point, QgsFeatureId atFeatureId, int beforeVertex );
/** Moves the vertex at the given position number,
* ring and item (first number is index 0), and feature
* to the given coordinates
*/
bool moveVertex( double x, double y, QgsFeatureId atFeatureId, int atVertex );
/** Moves the vertex at the given position number,
* ring and item (first number is index 0), and feature
* to the given coordinates
* @note available in python as moveVertexV2
*/
bool moveVertex( const QgsPointV2& p, QgsFeatureId atFeatureId, int atVertex ) /PyName=moveVertexV2/;
/** Deletes a vertex from a feature.
* @param featureId ID of feature to remove vertex from
* @param vertex index of vertex to delete
* @note added in QGIS 2.14
*/
EditResult deleteVertex( QgsFeatureId featureId, int vertex );
/** Deletes the selected features
* @return true in case of success and false otherwise
*/
bool deleteSelectedFeatures( int *deletedCount = 0 );
/** Adds a ring to polygon/multipolygon features
* @param ring ring to add
* @param featureId if specified, feature ID for feature ring was added to will be stored in this parameter
* @return
* 0 in case of success,
* 1 problem with feature type,
* 2 ring not closed,
* 3 ring not valid,
* 4 ring crosses existing rings,
* 5 no feature found where ring can be inserted
* 6 layer not editable
*/
int addRing( const QList<QgsPoint>& ring, QgsFeatureId* featureId = 0 );
/** Adds a ring to polygon/multipolygon features (takes ownership)
* @param ring ring to add
* @param featureId if specified, feature ID for feature ring was added to will be stored in this parameter
* @return
* 0 in case of success
* 1 problem with feature type
* 2 ring not closed
* 6 layer not editable
* @note available in python as addCurvedRing
*/
int addRing( QgsCurve* ring /Transfer/, QgsFeatureId* featureId = 0 ) /PyName=addCurvedRing/;
/** Adds a new part polygon to a multipart feature
* @return
* 0 in case of success,
* 1 if selected feature is not multipart,
* 2 if ring is not a valid geometry,
* 3 if new polygon ring not disjoint with existing rings,
* 4 if no feature was selected,
* 5 if several features are selected,
* 6 if selected geometry not found
* 7 layer not editable
*/
int addPart( const QList<QgsPoint>& ring );
/** Adds a new part polygon to a multipart feature
* @return
* 0 in case of success,
* 1 if selected feature is not multipart,
* 2 if ring is not a valid geometry,
* 3 if new polygon ring not disjoint with existing rings,
* 4 if no feature was selected,
* 5 if several features are selected,
* 6 if selected geometry not found
* 7 layer not editable
* @note available in python bindings as addPartV2
*/
int addPart( const QList<QgsPointV2>& ring ) /PyName=addPartV2/;
//! @note available in python as addCurvedPart
int addPart( QgsCurve* ring /Transfer/ ) /PyName=addCurvedPart/;
/** Translates feature by dx, dy
* @param featureId id of the feature to translate
* @param dx translation of x-coordinate
* @param dy translation of y-coordinate
* @return 0 in case of success
*/
int translateFeature( QgsFeatureId featureId, double dx, double dy );
/** Splits parts cut by the given line
* @param splitLine line that splits the layer features
* @param topologicalEditing true if topological editing is enabled
* @return
* 0 in case of success,
* 4 if there is a selection but no feature split
*/
int splitParts( const QList<QgsPoint>& splitLine, bool topologicalEditing = false );
/** Splits features cut by the given line
* @param splitLine line that splits the layer features
* @param topologicalEditing true if topological editing is enabled
* @return
* 0 in case of success,
* 4 if there is a selection but no feature split
*/
int splitFeatures( const QList<QgsPoint>& splitLine, bool topologicalEditing = false );
/** Adds topological points for every vertex of the geometry.
* @param geom the geometry where each vertex is added to segments of other features
* @note geom is not going to be modified by the function
* @return 0 in case of success
*/
int addTopologicalPoints( const QgsGeometry& geom );
/** Adds a vertex to segments which intersect point p but don't
* already have a vertex there. If a feature already has a vertex at position p,
* no additional vertex is inserted. This method is useful for topological
* editing.
* @param p position of the vertex
* @return 0 in case of success
*/
int addTopologicalPoints( const QgsPoint& p );
/** Inserts vertices to the snapped segments.
* This is useful for topological editing if snap to segment is enabled.
* @param snapResults results collected from the snapping operation
* @return 0 in case of success
*/
int insertSegmentVerticesForSnap( const QList<QgsSnappingResult>& snapResults );
/** Access to labeling configuration.
* @note added in 2.12
* @note not available in Python bindings
*/
// const QgsAbstractVectorLayerLabeling* labeling() const { return mLabeling; }
/** Set labeling configuration. Takes ownership of the object.
* @note added in 2.12
* @note not available in Python bindings
*/
// void setLabeling( QgsAbstractVectorLayerLabeling* labeling );
/** Returns true if the provider is in editing mode */
virtual bool isEditable() const;
virtual bool isSpatial() const;
/** Returns true if the provider has been modified since the last commit */
virtual bool isModified() const;
/** Snaps a point to the closest vertex if there is one within the snapping tolerance
* @param point The point which is set to the position of a vertex if there is one within the snapping tolerance.
* If there is no point within this tolerance, point is left unchanged.
* @param tolerance The snapping tolerance
* @return true if the point has been snapped, false if no vertex within search tolerance
*/
bool snapPoint( QgsPoint& point, double tolerance );
/** Snaps to segment or vertex within given tolerance
* @param startPoint point to snap (in layer coordinates)
* @param snappingTolerance distance tolerance for snapping
* @param snappingResults snapping results. Key is the distance between startPoint and snapping target
* @param snap_to to segment / to vertex
* @return 0 in case of success
*/
int snapWithContext( const QgsPoint& startPoint,
double snappingTolerance,
QMultiMap < double, QgsSnappingResult > &snappingResults /Out/,
QgsSnapper::SnappingType snap_to );
/** Synchronises with changes in the datasource */
virtual void reload();
/** Return new instance of QgsMapLayerRenderer that will be used for rendering of given context
* @note added in 2.4
*/
virtual QgsMapLayerRenderer* createMapRenderer( QgsRenderContext& rendererContext ) /Factory/;
/** Return the extent of the layer */
QgsRectangle extent() const;
/**
* Returns the list of fields of this layer.
* This also includes fields which have not yet been saved to the provider.
*
* @return A list of fields
*/
QgsFields fields() const;
/**
* Returns the list of fields of this layer.
* This also includes fields which have not yet been saved to the provider.
* Alias for {@link fields()}
*
* @return A list of fields
*/
QgsFields pendingFields() const;
/**
* Returns list of attribute indexes. i.e. a list from 0 ... fieldCount()
* Alias for {@link attributeList()}
*/
QgsAttributeList pendingAllAttributesList() const;
/**
* Returns list of attribute indexes. i.e. a list from 0 ... fieldCount()
* Alias for {@link attributeList()}
*/
QgsAttributeList attributeList() const;
/**
* Returns list of attributes making up the primary key
* Alias for {@link pkAttributeList()}
*/
QgsAttributeList pendingPkAttributesList() const;
/** Returns list of attributes making up the primary key */
QgsAttributeList pkAttributeList() const;
/**
* Returns feature count including changes which have not yet been committed
* Alias for {@link featureCount()}
*/
long pendingFeatureCount() const;
/**
* Returns feature count including changes which have not yet been committed
* If you need only the count of committed features call this method on this layer's provider.
*/
long featureCount() const;
/** Make layer read-only (editing disabled) or not
* @return false if the layer is in editing yet
*/
bool setReadOnly( bool readonly = true );
/** Change feature's geometry */
bool changeGeometry( QgsFeatureId fid, const QgsGeometry& geom );
/**
* Changes an attribute value (but does not commit it)
*
* @param fid The feature id of the feature to be changed
* @param field The index of the field to be updated
* @param newValue The value which will be assigned to the field
* @param oldValue The previous value to restore on undo (will otherwise be retrieved)
*
* @return true in case of success
*/
bool changeAttributeValue( QgsFeatureId fid, int field, const QVariant &newValue, const QVariant &oldValue = QVariant() );
/** Add an attribute field (but does not commit it)
* returns true if the field was added
*/
bool addAttribute( const QgsField &field );
/**
* Sets an alias (a display name) for attributes to display in dialogs
*
* @note Added in QGIS 3.0
*/
void setFieldAlias( int index, const QString& aliasString );
/**
* Removes an alias (a display name) for attributes to display in dialogs
*
* @note Added in QGIS 3.0
*/
void removeFieldAlias( int index );
/** Renames an attribute field (but does not commit it).
* @param attIndex attribute index
* @param newName new name of field
* @note added in QGIS 2.16
*/
bool renameAttribute( int index, const QString& newName );
/**
* Returns the alias of an attribute name or a null string if there is no alias.
*
* @see {attributeDisplayName( int attributeIndex )} which returns the field name
* if no alias is defined.
*/
QString attributeAlias( int index ) const;
/** Convenience function that returns the attribute alias if defined or the field name else */
QString attributeDisplayName( int index ) const;
const QMap< QString, QString >& attributeAliases() const;
QSet<QString> excludeAttributesWms() const;
void setExcludeAttributesWms( const QSet<QString>& att );
QSet<QString> excludeAttributesWfs() const;
void setExcludeAttributesWfs( const QSet<QString>& att );
/** Delete an attribute field (but does not commit it) */
bool deleteAttribute( int attr );
/**
* Deletes a list of attribute fields (but does not commit it)
*
* @param attrs the indices of the attributes to delete
* @return true if at least one attribute has been deleted
*
*/
bool deleteAttributes( QList<int> attrs );
/** Insert a copy of the given features into the layer (but does not commit it) */
bool addFeatures( QList<QgsFeature> features, bool makeSelected = true );
/** Delete a feature from the layer (but does not commit it) */
bool deleteFeature( QgsFeatureId fid );
/**
* Deletes a set of features from the layer (but does not commit it)
* @param fids The feature ids to delete
*
* @return false if the layer is not in edit mode or does not support deleting
* in case of an active transaction depends on the provider implementation
*/
bool deleteFeatures( const QgsFeatureIds& fids );
/**
* Attempts to commit any changes to disk. Returns the result of the attempt.
* If a commit fails, the in-memory changes are left alone.
*
* This allows editing to continue if the commit failed on e.g. a
* disallowed value in a Postgres database - the user can re-edit and try
* again.
*
* The commits occur in distinct stages,
* (add attributes, add features, change attribute values, change
* geometries, delete features, delete attributes)
* so if a stage fails, it's difficult to roll back cleanly.
* Therefore any error message also includes which stage failed so
* that the user has some chance of repairing the damage cleanly.
* @see commitErrors()
*/
bool commitChanges();
/** Returns a list containing any error messages generated when attempting
* to commit changes to the layer.
* @see commitChanges()
*/
QStringList commitErrors() const;
/** Stop editing and discard the edits
* @param deleteBuffer whether to delete editing buffer
*/
bool rollBack( bool deleteBuffer = true );
/** Get annotation form */
QString annotationForm() const;
/** Set annotation form for layer */
void setAnnotationForm( const QString& ui );
/**
* Get relations, where the foreign key is on this layer
*
* @param idx Only get relations, where idx forms part of the foreign key
* @return A list of relations
*/
QList<QgsRelation> referencingRelations( int idx ) const;
//! Buffer with uncommitted editing operations. Only valid after editing has been turned on.
QgsVectorLayerEditBuffer* editBuffer();
/**
* Create edit command for undo/redo operations
* @param text text which is to be displayed in undo window
*/
void beginEditCommand( const QString& text );
/** Finish edit command and add it to undo/redo stack */
void endEditCommand();
/** Destroy active command and reverts all changes in it */
void destroyEditCommand();
/** Editing vertex markers */
enum VertexMarkerType
{
SemiTransparentCircle,
Cross,
NoMarker
};
/** Draws a vertex symbol at (screen) coordinates x, y. (Useful to assist vertex editing.) */
static void drawVertexMarker( double x, double y, QPainter& p, QgsVectorLayer::VertexMarkerType type, int vertexSize );
/** Assembles mUpdatedFields considering provider fields, joined fields and added fields */
void updateFields();
/** Returns the calculated default value for the specified field index. The default
* value may be taken from a client side default value expression (see setDefaultValueExpression())
* or taken from the underlying data provider.
* @param index field index
* @param feature optional feature to use for default value evaluation. If passed,
* then properties from the feature (such as geometry) can be used when calculating
* the default value.
* @param context optional expression context to evaluate expressions again. If not
* specified, a default context will be created
* @return calculated default value
* @note added in QGIS 3.0
* @see setDefaultValueExpression()
*/
QVariant defaultValue( int index, const QgsFeature& feature = QgsFeature(),
QgsExpressionContext* context = nullptr ) const;
/** Sets an expression to use when calculating the default value for a field.
* @param index field index
* @param expression expression to evaluate when calculating default values for field. Pass
* an empty expression to clear the default.
* @note added in QGIS 3.0
* @see defaultValue()
* @see defaultValueExpression()
*/
void setDefaultValueExpression( int index, const QString& expression );
/** Returns the expression used when calculating the default value for a field.
* @param index field index
* @returns expression evaluated when calculating default values for field, or an
* empty string if no default is set
* @note added in QGIS 3.0
* @see defaultValue()
* @see setDefaultValueExpression()
*/
QString defaultValueExpression( int index ) const;
/**
* Returns any constraints which are present for a specified
* field index. These constraints may be inherited from the layer's data provider
* or may be set manually on the vector layer from within QGIS.
* @note added in QGIS 3.0
* @see setFieldConstraint()
*/
QgsFieldConstraints::Constraints fieldConstraints( int fieldIndex ) const;
/**
* Sets a constraint for a specified field index. Any constraints inherited from the layer's
* data provider will be kept intact and cannot be modified. Ie, calling this method only allows for new
* constraints to be added on top of the existing provider constraints.
* @note added in QGIS 3.0
* @see fieldConstraints()
* @see removeFieldConstraint()
*/
void setFieldConstraint( int index, QgsFieldConstraints::Constraint constraint, QgsFieldConstraints::ConstraintStrength strength = QgsFieldConstraints::ConstraintStrengthHard );
/**
* Removes a constraint for a specified field index. Any constraints inherited from the layer's
* data provider will be kept intact and cannot be removed.
* @note added in QGIS 3.0
* @see fieldConstraints()
* @see setFieldConstraint()
*/
void removeFieldConstraint( int index, QgsFieldConstraints::Constraint constraint );
/**
* Returns the constraint expression for for a specified field index, if set.
* @note added in QGIS 3.0
* @see fieldConstraints()
* @see constraintDescription()
* @see setConstraintExpression()
*/
QString constraintExpression( int index ) const;
/**
* Returns the descriptive name for the constraint expression for a specified field index.
* @note added in QGIS 3.0
* @see constraints()
* @see constraintExpression()
* @see setConstraintExpression()
*/
QString constraintDescription( int index ) const;
/**
* Set the constraint expression for the specified field index. An optional descriptive name for the constraint
* can also be set. Setting an empty expression will clear any existing expression constraint.
* @note added in QGIS 3.0
* @see constraintExpression()
* @see constraintDescription()
* @see constraints()
*/
void setConstraintExpression( int index, const QString& expression, const QString& description = QString() );
void setEditorWidgetSetup( int index, const QgsEditorWidgetSetup& setup );
QgsEditorWidgetSetup editorWidgetSetup( int index ) const;
/** Calculates a list of unique values contained within an attribute in the layer. Note that
* in some circumstances when unsaved changes are present for the layer then the returned list
* may contain outdated values (for instance when the attribute value in a saved feature has
* been changed inside the edit buffer then the previous saved value will be included in the
* returned list).
* @param index column index for attribute
* @param uniqueValues out: result list
* @param limit maximum number of values to return (or -1 if unlimited)
* @see minimumValue()
* @see maximumValue()
*/
void uniqueValues( int index, QList<QVariant> &uniqueValues /Out/, int limit = -1 ) const;
/**
* Returns unique string values of an attribute which contain a specified subset string. Subset
* matching is done in a case-insensitive manner. Note that
* in some circumstances when unsaved changes are present for the layer then the returned list
* may contain outdated values (for instance when the attribute value in a saved feature has
* been changed inside the edit buffer then the previous saved value will be included in the
* returned list).
* @param index column index for attribute
* @param substring substring to match (case insensitive)
* @param limit maxmum number of the values to return, or -1 to return all unique values
* @param feedback optional feedback object for canceling request
* @returns list of unique strings containing substring
*/
QStringList uniqueStringsMatching( int index, const QString& substring, int limit = -1,
QgsFeedback* feedback = nullptr ) const;
/** Returns the minimum value for an attribute column or an invalid variant in case of error.
* Note that in some circumstances when unsaved changes are present for the layer then the
* returned value may be outdated (for instance when the attribute value in a saved feature has
* been changed inside the edit buffer then the previous saved value may be returned as the minimum).
* @see maximumValue()
* @see uniqueValues()
*/
QVariant minimumValue( int index ) const;
/** Returns the maximum value for an attribute column or an invalid variant in case of error.
* Note that in some circumstances when unsaved changes are present for the layer then the
* returned value may be outdated (for instance when the attribute value in a saved feature has
* been changed inside the edit buffer then the previous saved value may be returned as the maximum).
* @see minimumValue()
* @see uniqueValues()
*/
QVariant maximumValue( int index ) const;
/** Calculates an aggregated value from the layer's features.
* @param aggregate aggregate to calculate
* @param fieldOrExpression source field or expression to use as basis for aggregated values.
* @param parameters parameters controlling aggregate calculation
* @param context expression context for expressions and filters
* @param ok if specified, will be set to true if aggregate calculation was successful
* @return calculated aggregate value
* @note added in QGIS 2.16
*/
QVariant aggregate( QgsAggregateCalculator::Aggregate aggregate,
const QString& fieldOrExpression,
const QgsAggregateCalculator::AggregateParameters& parameters = QgsAggregateCalculator::AggregateParameters(),
QgsExpressionContext* context = nullptr,
bool* ok = nullptr ) const;
QList< QVariant > getValues( const QString &fieldOrExpression, bool &ok, bool selectedOnly = false, QgsFeedback* feedback = 0 ) const;
QList< double > getDoubleValues( const QString &fieldOrExpression, bool &ok, bool selectedOnly = false, int* nullCount = 0, QgsFeedback* feedback = 0 ) const;
/** Set the blending mode used for rendering each feature */
void setFeatureBlendMode( QPainter::CompositionMode blendMode );
/** Returns the current blending mode for features */
QPainter::CompositionMode featureBlendMode() const;
/** Set the transparency for the vector layer */
void setLayerTransparency( int layerTransparency );
/** Returns the current transparency for the vector layer */
int layerTransparency() const;
QString metadata() const;
/** @note not available in python bindings */
// inline QgsGeometryCache* cache();
/** Set the simplification settings for fast rendering of features
* @note added in 2.2
*/
void setSimplifyMethod( const QgsVectorSimplifyMethod& simplifyMethod );
/** Returns the simplification settings for fast rendering of features
* @note added in 2.2
*/
const QgsVectorSimplifyMethod& simplifyMethod() const;
/** Returns whether the VectorLayer can apply the specified simplification hint
* @note Do not use in 3rd party code - may be removed in future version!
* @note added in 2.2
*/
bool simplifyDrawingCanbeApplied( const QgsRenderContext& renderContext, QgsVectorSimplifyMethod::SimplifyHint simplifyHint ) const;
/**
* @brief Return the conditional styles that are set for this layer. Style information is
* used to render conditional formatting in the attribute table.
* @return Return a QgsConditionalLayerStyles object holding the conditional attribute
* style information. Style information is generic and can be used for anything.
* @note added in QGIS 2.12
*/
QgsConditionalLayerStyles *conditionalStyles() const;
/**
* Get the attribute table configuration object.
* This defines the appearance of the attribute table.
*/
QgsAttributeTableConfig attributeTableConfig() const;
/**
* Set the attribute table configuration object.
* This defines the appearance of the attribute table.
*/
void setAttributeTableConfig( const QgsAttributeTableConfig& attributeTableConfig );
/**
* The mapTip is a pretty, html representation for feature information.
*
* It may also contain embedded expressions.
*
* @note added in 3.0
*/
QString mapTipTemplate() const;
/**
* The mapTip is a pretty, html representation for feature information.
*
* It may also contain embedded expressions.
*
* @note added in 3.0
*/
void setMapTipTemplate( const QString& mapTipTemplate );
QgsExpressionContext createExpressionContext() const;
/**
* Get the configuration of the form used to represent this vector layer.
* This is a writable configuration that can directly be changed in place.
*
* @return The configuration of this layers' form
*
* @note Added in QGIS 2.14
*/
QgsEditFormConfig editFormConfig() const;
/**
* Get the configuration of the form used to represent this vector layer.
* This is a writable configuration that can directly be changed in place.
*
* @return The configuration of this layers' form
*
* @note Added in QGIS 3.0
*/
void setEditFormConfig( const QgsEditFormConfig& editFormConfig );
public slots:
/**
* Select feature by its ID
*
* @param featureId The id of the feature to select
*
* @see select(QgsFeatureIds)
*/
void select( QgsFeatureId featureId );
/**
* Select features by their ID
*
* @param featureIds The ids of the features to select
*
* @see select(QgsFeatureId)
*/
void select( const QgsFeatureIds& featureIds );
/**
* Deselect feature by its ID
*
* @param featureId The id of the feature to deselect
*
* @see deselect(QgsFeatureIds)
*/
void deselect( const QgsFeatureId featureId );
/**
* Deselect features by their ID
*
* @param featureIds The ids of the features to deselect
*
* @see deselect(QgsFeatureId)
*/
void deselect( const QgsFeatureIds& featureIds );
/**
* Clear selection
*
* @see selectByIds()
*/
void removeSelection();
/** Update the extents for the layer. This is necessary if features are
* added/deleted or the layer has been subsetted.
*/
virtual void updateExtents();
/**
* Make layer editable.
* This starts an edit session on this layer. Changes made in this edit session will not
* be made persistent until {@link commitChanges()} is called and can be reverted by calling
* {@link rollBack()}.
*/
bool startEditing();
protected slots:
void invalidateSymbolCountedFlag();
signals:
/**
* This signal is emitted when selection was changed
*
* @param selected Newly selected feature ids
* @param deselected Ids of all features which have previously been selected but are not any more
* @param clearAndSelect In case this is set to true, the old selection was dismissed and the new selection corresponds to selected
*/
void selectionChanged( const QgsFeatureIds& selected, const QgsFeatureIds& deselected, const bool clearAndSelect );
/** This signal is emitted when modifications has been done on layer */
void layerModified();
/** Is emitted, when layer is checked for modifications. Use for last-minute additions */
void beforeModifiedCheck() const;
/** Is emitted, before editing on this layer is started */
void beforeEditingStarted();
/** Is emitted, when editing on this layer has started*/
void editingStarted();
/** Is emitted, when edited changes successfully have been written to the data provider */
void editingStopped();
/** Is emitted, before changes are committed to the data provider */
void beforeCommitChanges();
/** Is emitted, before changes are rolled back*/
void beforeRollBack();
/**
* Will be emitted, when a new attribute has been added to this vector layer.
* Applies only to types {@link QgsFields::OriginEdit}, {@link QgsFields::OriginProvider} and {@link QgsFields::OriginExpression }
*
* @param idx The index of the new attribute
*
* @see updatedFields()
*/
void attributeAdded( int idx );
/**
* Will be emitted, when an expression field is going to be added to this vector layer.
* Applies only to types {@link QgsFields::OriginExpression }
*
* @param fieldName The name of the attribute to be added
*/
void beforeAddingExpressionField( const QString& fieldName );
/**
* Will be emitted, when an attribute has been deleted from this vector layer.
* Applies only to types {@link QgsFields::OriginEdit}, {@link QgsFields::OriginProvider} and {@link QgsFields::OriginExpression }
*
* @param idx The index of the deleted attribute
*
* @see updatedFields()
*/
void attributeDeleted( int idx );
/**
* Will be emitted, when an expression field is going to be deleted from this vector layer.
* Applies only to types {@link QgsFields::OriginExpression }
*
* @param idx The index of the attribute to be deleted
*/
void beforeRemovingExpressionField( int idx );
/**
* Emitted when a new feature has been added to the layer
*
* @param fid The id of the new feature
*/
void featureAdded( QgsFeatureId fid );
/**
* Emitted when a feature has been deleted.
*
* If you do expensive operations in a slot connected to this, you should prever to use
* {@link featuresDeleted( const QgsFeatureIds& )}.
*
* @param fid The id of the feature which has been deleted
*/
void featureDeleted( QgsFeatureId fid );
/**
* Emitted when features have been deleted.
*
* If features are deleted within an edit command, this will only be emitted once at the end
* to allow connected slots to minimize the overhead.
* If features are deleted outside of an edit command, this signal will be emitted once per feature.
*
* @param fids The feature ids that have been deleted.
*/
void featuresDeleted( const QgsFeatureIds& fids );
/**
* Is emitted, whenever the fields available from this layer have been changed.
* This can be due to manually adding attributes or due to a join.
*/
void updatedFields();
/**
* Is emitted whenever an attribute value change is done in the edit buffer.
* Note that at this point the attribute change is not yet saved to the provider.
*
* @param fid The id of the changed feature
* @param idx The attribute index of the changed attribute
* @param value The new value of the attribute
*/
void attributeValueChanged( QgsFeatureId fid, int idx, const QVariant& value );
/**
* Is emitted whenever a geometry change is done in the edit buffer.
* Note that at this point the geometry change is not yet saved to the provider.
*
* @param fid The id of the changed feature
* @param geometry The new geometry
*/
void geometryChanged( QgsFeatureId fid, const QgsGeometry& geometry );
/** This signal is emitted, when attributes are deleted from the provider */
void committedAttributesDeleted( const QString& layerId, const QgsAttributeList& deletedAttributes );
/** This signal is emitted, when attributes are added to the provider */
void committedAttributesAdded( const QString& layerId, const QList<QgsField>& addedAttributes );
/** This signal is emitted, when features are added to the provider */
void committedFeaturesAdded( const QString& layerId, const QgsFeatureList& addedFeatures );
/** This signal is emitted, when features are deleted from the provider */
void committedFeaturesRemoved( const QString& layerId, const QgsFeatureIds& deletedFeatureIds );
/** This signal is emitted, when attribute value changes are saved to the provider */
void committedAttributeValuesChanges( const QString& layerId, const QgsChangedAttributesMap& changedAttributesValues );
/** This signal is emitted, when geometry changes are saved to the provider */
void committedGeometriesChanges( const QString& layerId, const QgsGeometryMap& changedGeometries );
/** Emitted when the font family defined for labeling layer is not found on system */
void labelingFontNotFound( QgsVectorLayer* layer, const QString& fontfamily );
/** Signal emitted when setFeatureBlendMode() is called */
void featureBlendModeChanged( QPainter::CompositionMode blendMode );
/** Signal emitted when setLayerTransparency() is called */
void layerTransparencyChanged( int layerTransparency );
/**
* Signal emitted when a new edit command has been started
*
* @param text Description for this edit command
*/
void editCommandStarted( const QString& text );
/**
* Signal emitted, when an edit command successfully ended
* @note This does not mean it is also committed, only that it is written
* to the edit buffer. See {@link beforeCommitChanges()}
*/
void editCommandEnded();
/**
* Signal emitted, whan an edit command is destroyed
* @note This is not a rollback, it is only related to the current edit command.
* See {@link beforeRollBack()}
*/
void editCommandDestroyed();
/**
* Signal emitted whenever the symbology (QML-file) for this layer is being read.
* If there is custom style information saved in the file, you can connect to this signal
* and update the layer style accordingly.
*
* @param element The XML layer style element.
*
* @param errorMessage Write error messages into this string.
*/
void readCustomSymbology( const QDomElement& element, QString& errorMessage );
/**
* Signal emitted whenever the symbology (QML-file) for this layer is being written.
* If there is custom style information you want to save to the file, you can connect
* to this signal and update the element accordingly.
*
* @param element The XML element where you can add additional style information to.
* @param doc The XML document that you can use to create new XML nodes.
* @param errorMessage Write error messages into this string.
*/
void writeCustomSymbology( QDomElement& element, QDomDocument& doc, QString& errorMessage ) const;
/**
* Emitted when the map tip changes
*
* @note added in 3.0
*/
void mapTipTemplateChanged();
/**
* Emitted when the display expression changes
*
* @note added in 3.0
*/
void displayExpressionChanged();
/**
* Signals an error related to this vector layer.
*/
void raiseError( const QString& msg );
/**
* Will be emitted whenever the edit form configuration of this layer changes.
*
* @Note added in QGIS 3.0
*/
void editFormConfigChanged();
/**
* Emitted when the read only state of this layer is changed.
* Only applies to manually set readonly state, not to the edit mode.
*
* @note Added in QGIS 3.0
*/
void readOnlyChanged();
protected:
/** Set the extent */
void setExtent( const QgsRectangle &rect );
private: // Private methods
/** Vector layers are not copyable */
QgsVectorLayer( const QgsVectorLayer & rhs );
};