QGIS API Documentation  2.5.0-Master
 All Classes Namespaces Files Functions Variables Typedefs Enumerations Enumerator Friends Macros Modules Pages
Classes | Public Types | Public Slots | Signals | Public Member Functions | Static Public Member Functions | Protected Slots | Protected Member Functions | Friends | List of all members
QgsVectorLayer Class Reference

Represents a vector layer which manages a vector based data sets. More...

#include <qgsvectorlayer.h>

Inheritance diagram for QgsVectorLayer:
Inheritance graph
[legend]

Classes

struct  GroupData
 
struct  RangeData
 
struct  TabData
 
struct  ValueRelationData
 

Public Types

enum  EditorLayout { GeneratedLayout = 0, TabLayout = 1, UiFileLayout = 2 }
 The different types to layout the attribute editor. More...
 
enum  EditType {
  LineEdit, UniqueValues, UniqueValuesEditable, ValueMap,
  Classification, EditRange, SliderRange, CheckBox,
  FileName, Enumeration, Immutable, Hidden,
  TextEdit, Calendar, DialRange, ValueRelation,
  UuidGenerator, Photo, WebView, Color,
  EditorWidgetV2
}
 
enum  FeatureFormSuppress { SuppressDefault = 0, SuppressOn = 1, SuppressOff = 2 }
 Types of feature form suppression after feature creation. More...
 
enum  VertexMarkerType { SemiTransparentCircle, Cross, NoMarker }
 Editing vertex markers. More...
 
- Public Types inherited from QgsMapLayer
enum  LayerType { VectorLayer, RasterLayer, PluginLayer }
 Layers enum defining the types of layers that can be added to a map. More...
 

Public Slots

void select (const QgsFeatureId &featureId)
 Select feature by its ID. More...
 
void select (const QgsFeatureIds &featureIds)
 Select features by their ID. More...
 
void deselect (const QgsFeatureId featureId)
 Deselect feature by its ID. More...
 
void deselect (const QgsFeatureIds &featureIds)
 Deselect features by their ID. More...
 
void removeSelection ()
 Clear selection. More...
 
virtual void updateExtents ()
 Update the extents for the layer. More...
 
void checkJoinLayerRemove (QString theLayerId)
 Check if there is a join with a layer that will be removed. More...
 
- Public Slots inherited from QgsMapLayer
virtual void invalidTransformInput ()
 Event handler for when a coordinate transform fails due to bad vertex error. More...
 
void setMinimumScale (float theMinScale)
 Accessor and mutator for the minimum scale denominator member. More...
 
float minimumScale () const
 
void setMaximumScale (float theMaxScale)
 Accessor and mutator for the maximum scale denominator member. More...
 
float maximumScale () const
 
void toggleScaleBasedVisibility (bool theVisibilityFlag)
 Accessor and mutator for the scale based visilibility flag. More...
 
bool hasScaleBasedVisibility () const
 
Q_DECL_DEPRECATED void clearCacheImage ()
 Clear cached image. More...
 
void triggerRepaint ()
 Will advice the map canvas (and any other interested party) that this layer requires to be repainted. More...
 
virtual QDateTime timestamp () const
 Time stamp of data source in the moment when data/metadata were loaded by provider. More...
 

Signals

void selectionChanged (const QgsFeatureIds selected, const QgsFeatureIds deselected, const bool clearAndSelect)
 This signal is emitted when selection was changed. More...
 
void selectionChanged ()
 This signal is emitted when selection was changed. More...
 
void layerModified ()
 This signal is emitted when modifications has been done on layer. More...
 
void beforeModifiedCheck () const
 Is emitted, when layer is checked for modifications. More...
 
void editingStarted ()
 Is emitted, when editing on this layer has started. More...
 
void editingStopped ()
 Is emitted, when edited changes successfully have been written to the data provider. More...
 
void beforeCommitChanges ()
 Is emitted, before changes are commited to the data provider. More...
 
void beforeRollBack ()
 Is emitted, before changes are rolled back. More...
 
void attributeAdded (int idx)
 Will be emitted, when a new attribute has been added to this vector layer. More...
 
void attributeDeleted (int idx)
 Will be emitted, when an attribute has been deleted from this vector layer. More...
 
void featureAdded (QgsFeatureId fid)
 
void featureDeleted (QgsFeatureId fid)
 
void updatedFields ()
 Is emitted, whenever the fields available from this layer have been changed. More...
 
void layerDeleted ()
 
void attributeValueChanged (QgsFeatureId fid, int idx, const QVariant &)
 
void geometryChanged (QgsFeatureId fid, QgsGeometry &geom)
 
void committedAttributesDeleted (const QString &layerId, const QgsAttributeList &deletedAttributes)
 Signals emitted after committing changes. More...
 
void committedAttributesAdded (const QString &layerId, const QList< QgsField > &addedAttributes)
 
void committedFeaturesAdded (const QString &layerId, const QgsFeatureList &addedFeatures)
 
void committedFeaturesRemoved (const QString &layerId, const QgsFeatureIds &deletedFeatureIds)
 
void committedAttributeValuesChanges (const QString &layerId, const QgsChangedAttributesMap &changedAttributesValues)
 
void committedGeometriesChanges (const QString &layerId, const QgsGeometryMap &changedGeometries)
 
void saveLayerToProject ()
 
void labelingFontNotFound (QgsVectorLayer *layer, const QString &fontfamily)
 Emitted when the font family defined for labeling layer is not found on system. More...
 
void featureBlendModeChanged (const QPainter::CompositionMode &blendMode)
 Signal emitted when setFeatureBlendMode() is called. More...
 
void layerTransparencyChanged (int layerTransparency)
 Signal emitted when setLayerTransparency() is called. More...
 
void editCommandStarted (const QString &text)
 Signal emitted when a new edit command has been started. More...
 
void editCommandEnded ()
 Signal emitted, when an edit command successfully ended. More...
 
void editCommandDestroyed ()
 Signal emitted, whan an edit command is destroyed. More...
 
void readCustomSymbology (const QDomElement &element, QString &errorMessage)
 Signal emitted whenever the symbology (QML-file) for this layer is being read. More...
 
void writeCustomSymbology (QDomElement &element, QDomDocument &doc, QString &errorMessage) const
 Signal emitted whenever the symbology (QML-file) for this layer is being written. More...
 
- Signals inherited from QgsMapLayer
void drawingProgress (int theProgress, int theTotalSteps)
 
void statusChanged (QString theStatus)
 Emit a signal with status (e.g. More...
 
void layerNameChanged ()
 Emit a signal that the layer name has been changed. More...
 
void layerCrsChanged ()
 Emit a signal that layer's CRS has been reset. More...
 
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. More...
 
void screenUpdateRequested ()
 
void recalculateExtents ()
 This is used to send a request that any mapcanvas using this layer update its extents. More...
 
void dataChanged ()
 data of layer changed More...
 
void blendModeChanged (const QPainter::CompositionMode &blendMode)
 Signal emitted when the blend mode is changed, through QgsMapLayer::setBlendMode() More...
 
void rendererChanged ()
 Signal emitted when renderer is changed. More...
 
void legendChanged ()
 Signal emitted when legend of the layer has changed. More...
 

Public Member Functions

 QgsVectorLayer (QString path=QString::null, QString baseName=QString::null, QString providerLib=QString::null, bool loadDefaultStyleFlag=true)
 Constructor - creates a vector layer. More...
 
virtual ~QgsVectorLayer ()
 Destructor. More...
 
QString storageType () const
 Returns the permanent storage type for this layer as a friendly name. More...
 
QString capabilitiesString () const
 Capabilities for this layer in a friendly format. More...
 
QString dataComment () const
 Returns a comment for the data in the layer. More...
 
void setDisplayField (QString fldName="")
 Set the primary display field to be used in the identify results dialog. More...
 
const QString displayField () const
 Returns the primary display field name used in the identify results dialog. More...
 
void setDisplayExpression (const QString &displayExpression)
 Set the preview expression, used to create a human readable preview string. More...
 
const QString displayExpression ()
 Get the preview expression, used to create a human readable preview string. More...
 
QgsVectorDataProviderdataProvider ()
 Returns the data provider. More...
 
const QgsVectorDataProviderdataProvider () const
 Returns the data provider in a const-correct manner. More...
 
void setProviderEncoding (const QString &encoding)
 Sets the textencoding of the data provider. More...
 
void setCoordinateSystem ()
 Setup the coordinate system transformation for the layer. More...
 
bool addJoin (const QgsVectorJoinInfo &joinInfo)
 Joins another vector layer to this layer. More...
 
void removeJoin (const QString &joinLayerId)
 Removes a vector layer join. More...
 
const QList< QgsVectorJoinInfo > & vectorJoins () const
 
void addExpressionField (const QString &exp, const QgsField &fld)
 Add a new field which is calculated by the expression specified. More...
 
void removeExpressionField (int index)
 Remove an expression field. More...
 
QgsLabellabel ()
 Get the label object associated with this layer. More...
 
const QgsLabellabel () const
 
QgsAttributeActionactions ()
 
int selectedFeatureCount ()
 The number of features that are selected in this layer. More...
 
void select (QgsRectangle &rect, bool addToSelection)
 Select features found within the search rectangle (in layer's coordinates) More...
 
void modifySelection (QgsFeatureIds selectIds, QgsFeatureIds deselectIds)
 Modifies the current selection on this layer. More...
 
void invertSelection ()
 Select not selected features and deselect selected ones. More...
 
void selectAll ()
 Select all the features. More...
 
QgsFeatureIds allFeatureIds ()
 Get all feature Ids. More...
 
void invertSelectionInRectangle (QgsRectangle &rect)
 Invert selection of features found within the search rectangle (in layer's coordinates) More...
 
QgsFeatureList selectedFeatures ()
 Get a copy of the user-selected features. More...
 
QgsFeatureIterator selectedFeaturesIterator (QgsFeatureRequest request=QgsFeatureRequest())
 Get an iterator of the selected features. More...
 
const QgsFeatureIdsselectedFeaturesIds () const
 Return reference to identifiers of selected features. More...
 
void setSelectedFeatures (const QgsFeatureIds &ids)
 Change selection to the new set of features. More...
 
QgsRectangle boundingBoxOfSelected ()
 Returns the bounding box of the selected features. More...
 
void setDiagramRenderer (QgsDiagramRendererV2 *r)
 Sets diagram rendering object (takes ownership) More...
 
const QgsDiagramRendererV2diagramRenderer () const
 
void setDiagramLayerSettings (const QgsDiagramLayerSettings &s)
 
const QgsDiagramLayerSettingsdiagramLayerSettings () const
 
QgsFeatureRendererV2rendererV2 ()
 Return renderer V2. More...
 
void setRendererV2 (QgsFeatureRendererV2 *r)
 Set renderer V2. More...
 
QGis::GeometryType geometryType () const
 Returns point, line or polygon. More...
 
bool hasGeometryType () const
 Returns true if this is a geometry layer and false in case of NoGeometry (table only) or UnknownGeometry. More...
 
QGis::WkbType wkbType () const
 Returns the WKBType or WKBUnknown in case of error. More...
 
QString providerType () const
 Return the provider type for this layer. More...
 
virtual bool readXml (const QDomNode &layer_node)
 reads vector layer specific state from project file Dom node. More...
 
virtual bool writeXml (QDomNode &layer_node, QDomDocument &doc)
 write vector layer specific state to project file Dom node. More...
 
virtual void saveStyleToDatabase (QString name, QString description, bool useAsDefault, QString uiFileContent, QString &msgError)
 Save named and sld style of the layer to the style table in the db. More...
 
virtual int listStylesInDatabase (QStringList &ids, QStringList &names, QStringList &descriptions, QString &msgError)
 Lists all the style in db split into related to the layer and not related to. More...
 
virtual QString getStyleFromDatabase (QString styleId, QString &msgError)
 Will return the named style corresponding to style id provided. More...
 
virtual QString loadNamedStyle (const QString &theURI, bool &theResultFlag, bool loadFromLocalDb)
 Load a named style from file/local db/datasource db. More...
 
virtual QString loadNamedStyle (const QString &theURI, bool &theResultFlag)
 Calls loadNamedStyle( theURI, theResultFlag, false ); Retained for backward compatibility. More...
 
virtual bool applyNamedStyle (QString namedStyle, QString errorMsg)
 
QgsAttributeEditorElementattributeEditorElementFromDomElement (QDomElement &elem, QObject *parent)
 convert a saved attribute editor element into a AttributeEditor structure as it's used internally. More...
 
bool readSymbology (const QDomNode &node, QString &errorMessage)
 Read the symbology for the current layer from the Dom node supplied. More...
 
bool writeSymbology (QDomNode &node, QDomDocument &doc, QString &errorMessage) const
 Write the symbology for the layer into the docment provided. More...
 
bool writeSld (QDomNode &node, QDomDocument &doc, QString &errorMessage) const
 
bool readSld (const QDomNode &node, QString &errorMessage)
 
virtual long featureCount () const
 Number of features in the layer. More...
 
long featureCount (QgsSymbolV2 *symbol)
 Number of features rendered with specified symbol. More...
 
bool countSymbolFeatures (bool showProgress=true)
 Count features for symbols. More...
 
virtual bool setSubsetString (QString subset)
 Set the string (typically sql) used to define a subset of the layer. More...
 
virtual QString subsetString ()
 Get the string (typically sql) used to define a subset of the layer. More...
 
QgsFeatureIterator getFeatures (const QgsFeatureRequest &request=QgsFeatureRequest())
 Query the provider for features specified in request. More...
 
bool addFeature (QgsFeature &f, bool alsoUpdateExtent=true)
 Adds a feature. More...
 
bool updateFeature (QgsFeature &f)
 Updates an existing feature. More...
 
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. More...
 
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. More...
 
bool deleteVertex (QgsFeatureId atFeatureId, int atVertex)
 Deletes a vertex from a feature. More...
 
bool deleteSelectedFeatures ()
 Deletes the selected features. More...
 
int addRing (const QList< QgsPoint > &ring)
 Adds a ring to polygon/multipolygon features. More...
 
int addPart (const QList< QgsPoint > &ring)
 Adds a new part polygon to a multipart feature. More...
 
int translateFeature (QgsFeatureId featureId, double dx, double dy)
 Translates feature by dx, dy. More...
 
int splitParts (const QList< QgsPoint > &splitLine, bool topologicalEditing=false)
 Splits parts cut by the given line. More...
 
int splitFeatures (const QList< QgsPoint > &splitLine, bool topologicalEditing=false)
 Splits features cut by the given line. More...
 
Q_DECL_DEPRECATED int removePolygonIntersections (QgsGeometry *geom, QgsFeatureIds ignoreFeatures=QgsFeatureIds())
 Changes the specified geometry such that it has no intersections with other polygon (or multipolygon) geometries in this vector layer. More...
 
int addTopologicalPoints (QgsGeometry *geom)
 Adds topological points for every vertex of the geometry. More...
 
int addTopologicalPoints (const QgsPoint &p)
 Adds a vertex to segments which intersect point p but don't already have a vertex there. More...
 
int insertSegmentVerticesForSnap (const QList< QgsSnappingResult > &snapResults)
 Inserts vertices to the snapped segments. More...
 
void enableLabels (bool on)
 Set labels on. More...
 
bool hasLabelsEnabled () const
 Label is on. More...
 
virtual bool isEditable () const
 Returns true if the provider is in editing mode. More...
 
virtual bool isReadOnly () const
 Returns true if the provider is in read-only mode. More...
 
virtual bool isModified () const
 Returns true if the provider has been modified since the last commit. More...
 
bool snapPoint (QgsPoint &point, double tolerance)
 Snaps a point to the closest vertex if there is one within the snapping tolerance. More...
 
int snapWithContext (const QgsPoint &startPoint, double snappingTolerance, QMultiMap< double, QgsSnappingResult > &snappingResults, QgsSnapper::SnappingType snap_to)
 Snaps to segment or vertex within given tolerance. More...
 
virtual void reload ()
 Synchronises with changes in the datasource. More...
 
virtual QgsMapLayerRenderercreateMapRenderer (QgsRenderContext &rendererContext)
 Return new instance of QgsMapLayerRenderer that will be used for rendering of given context. More...
 
bool draw (QgsRenderContext &rendererContext)
 Draws the layer. More...
 
void drawLabels (QgsRenderContext &rendererContext)
 Draws the layer labels using coordinate transformation. More...
 
QgsRectangle extent ()
 Return the extent of the layer as a QRect. More...
 
const QgsFieldspendingFields () const
 returns field list in the to-be-committed state More...
 
QgsAttributeList pendingAllAttributesList ()
 returns list of attributes More...
 
QgsAttributeList pendingPkAttributesList ()
 returns list of attribute making up the primary key More...
 
int pendingFeatureCount ()
 returns feature count after commit More...
 
bool setReadOnly (bool readonly=true)
 Make layer read-only (editing disabled) or not. More...
 
bool startEditing ()
 Make layer editable. More...
 
bool changeGeometry (QgsFeatureId fid, QgsGeometry *geom)
 change feature's geometry More...
 
Q_DECL_DEPRECATED bool changeAttributeValue (QgsFeatureId fid, int field, QVariant value, bool emitSignal)
 Changes an attribute value (but does not commit it) More...
 
bool changeAttributeValue (QgsFeatureId fid, int field, const QVariant &newValue, const QVariant &oldValue=QVariant())
 Changes an attribute value (but does not commit it) More...
 
bool addAttribute (const QgsField &field)
 add an attribute field (but does not commit it) returns true if the field was added More...
 
void addAttributeAlias (int attIndex, QString aliasString)
 Sets an alias (a display name) for attributes to display in dialogs. More...
 
void remAttributeAlias (int attIndex)
 Removes an alias (a display name) for attributes to display in dialogs. More...
 
void addAttributeEditorWidget (QgsAttributeEditorElement *data)
 Adds a tab (for the attribute editor form) holding groups and fields. More...
 
const QString editorWidgetV2 (int fieldIdx) const
 Get the id for the editor widget used to represent the field at the given index. More...
 
const QString editorWidgetV2 (const QString &fieldName) const
 Get the id for the editor widget used to represent the field at the given index. More...
 
const QgsEditorWidgetConfig editorWidgetV2Config (int fieldIdx) const
 Get the configuration for the editor widget used to represent the field at the given index. More...
 
const QgsEditorWidgetConfig editorWidgetV2Config (const QString &fieldName) const
 Get the configuration for the editor widget used to represent the field at the given index. More...
 
QList
< QgsAttributeEditorElement * > & 
attributeEditorElements ()
 Returns a list of tabs holding groups and fields. More...
 
void clearAttributeEditorWidgets ()
 Clears all the tabs for the attribute editor form. More...
 
QString attributeAlias (int attributeIndex) const
 Returns the alias of an attribute name or an empty string if there is no alias. More...
 
QString attributeDisplayName (int attributeIndex) const
 Convenience function that returns the attribute alias if defined or the field name else. More...
 
const QMap< QString, QString > & attributeAliases () const
 
const QSet< QString > & excludeAttributesWMS () const
 
void setExcludeAttributesWMS (const QSet< QString > &att)
 
const QSet< QString > & excludeAttributesWFS () const
 
void setExcludeAttributesWFS (const QSet< QString > &att)
 
bool deleteAttribute (int attr)
 delete an attribute field (but does not commit it) More...
 
bool deleteAttributes (QList< int > attrs)
 Deletes a list of attribute fields (but does not commit it) More...
 
bool addFeatures (QgsFeatureList features, bool makeSelected=true)
 Insert a copy of the given features into the layer (but does not commit it) More...
 
bool deleteFeature (QgsFeatureId fid)
 delete a feature from the layer (but does not commit it) More...
 
bool commitChanges ()
 Attempts to commit any changes to disk. More...
 
const QStringList & commitErrors ()
 
bool rollBack (bool deleteBuffer=true)
 Stop editing and discard the edits. More...
 
Q_DECL_DEPRECATED EditType editType (int idx)
 Get edit type. More...
 
Q_DECL_DEPRECATED void setEditType (int idx, EditType edit)
 Get edit type. More...
 
EditorLayout editorLayout ()
 get the active layout for the attribute editor for this layer More...
 
void setEditorLayout (EditorLayout editorLayout)
 set the active layout for the attribute editor for this layer More...
 
void setEditorWidgetV2 (int attrIdx, const QString &widgetType)
 Set the editor widget type for a field. More...
 
void setEditorWidgetV2Config (int attrIdx, const QgsEditorWidgetConfig &config)
 Set the editor widget config for a field. More...
 
Q_DECL_DEPRECATED void setCheckedState (int idx, QString checked, QString notChecked)
 Set string representing 'true' for a checkbox. More...
 
QString editForm ()
 get edit form More...
 
void setEditForm (QString ui)
 set edit form More...
 
QgsVectorLayer::FeatureFormSuppress featureFormSuppress () const
 Type of feature form pop-up suppression after feature creation (overrides app setting) More...
 
void setFeatureFormSuppress (QgsVectorLayer::FeatureFormSuppress s)
 Set type of feature form pop-up suppression after feature creation (overrides app setting) More...
 
QString annotationForm () const
 get annotation form More...
 
void setAnnotationForm (const QString &ui)
 set annotation form for layer More...
 
QString editFormInit ()
 get python function for edit form initialization More...
 
void setEditFormInit (QString function)
 set python function for edit form initialization More...
 
Q_DECL_DEPRECATED QMap
< QString, QVariant > 
valueMap (int idx)
 Access value map. More...
 
Q_DECL_DEPRECATED RangeData range (int idx)
 Access range widget config data. More...
 
ValueRelationData valueRelation (int idx)
 Access value relation widget data. More...
 
QList< QgsRelationreferencingRelations (int idx)
 Get relations, where the foreign key is on this layer. More...
 
Q_DECL_DEPRECATED QString dateFormat (int idx)
 Access date format. More...
 
Q_DECL_DEPRECATED QSize widgetSize (int idx)
 Access widget size for photo and webview widget. More...
 
bool fieldEditable (int idx)
 is edit widget editable More...
 
bool labelOnTop (int idx)
 label widget on top More...
 
void setFieldEditable (int idx, bool editable)
 set edit widget editable More...
 
void setLabelOnTop (int idx, bool onTop)
 label widget on top More...
 
QgsVectorLayerEditBuffereditBuffer ()
 Buffer with uncommitted editing operations. Only valid after editing has been turned on. More...
 
void beginEditCommand (QString text)
 Create edit command for undo/redo operations. More...
 
void endEditCommand ()
 Finish edit command and add it to undo/redo stack. More...
 
void destroyEditCommand ()
 Destroy active command and reverts all changes in it. More...
 
int fieldNameIndex (const QString &fieldName) const
 Returns the index of a field name or -1 if the field does not exist. More...
 
void updateFields ()
 Assembles mUpdatedFields considering provider fields, joined fields and added fields. More...
 
void createJoinCaches ()
 Caches joined attributes if required (and not already done) More...
 
void uniqueValues (int index, QList< QVariant > &uniqueValues, int limit=-1)
 Returns unique values for column. More...
 
QVariant minimumValue (int index)
 Returns minimum value for an attribute column or invalid variant in case of error. More...
 
QVariant maximumValue (int index)
 Returns maximum value for an attribute column or invalid variant in case of error. More...
 
void setFeatureBlendMode (const QPainter::CompositionMode &blendMode)
 Write blend mode for features. More...
 
QPainter::CompositionMode featureBlendMode () const
 Read blend mode for layer. More...
 
void setLayerTransparency (int layerTransparency)
 Write transparency for layer. More...
 
int layerTransparency () const
 Read transparency for layer. More...
 
QString metadata ()
 Obtain Metadata for this layer. More...
 
QgsGeometryCachecache ()
 
void setSimplifyMethod (const QgsVectorSimplifyMethod &simplifyMethod)
 Set the simplification settings for fast rendering of features. More...
 
const QgsVectorSimplifyMethodsimplifyMethod () const
 Returns the simplification settings for fast rendering of features. More...
 
bool simplifyDrawingCanbeApplied (const QgsRenderContext &renderContext, QgsVectorSimplifyMethod::SimplifyHint simplifyHint) const
 Returns whether the VectorLayer can apply the specified simplification hint. More...
 
- Public Member Functions inherited from QgsMapLayer
 QgsMapLayer (QgsMapLayer::LayerType type=VectorLayer, QString lyrname=QString::null, QString source=QString::null)
 Constructor. More...
 
virtual ~QgsMapLayer ()
 Destructor. More...
 
QgsMapLayer::LayerType type () const
 Get the type of the layer. More...
 
QString id () const
 Get this layer's unique ID, this ID is used to access this layer from map layer registry. More...
 
void setLayerName (const QString &name)
 Set the display name of the layer. More...
 
const QString & name () const
 Get the display name of the layer. More...
 
const QString & originalName () const
 Get the original name of the layer. More...
 
void setTitle (const QString &title)
 
const QString & title () const
 
void setAbstract (const QString &abstract)
 
const QString & abstract () const
 
void setKeywordList (const QString &keywords)
 
const QString & keywordList () const
 
void setDataUrl (const QString &dataUrl)
 
const QString & dataUrl () const
 
void setDataUrlFormat (const QString &dataUrlFormat)
 
const QString & dataUrlFormat () const
 
void setAttribution (const QString &attrib)
 
const QString & attribution () const
 
void setAttributionUrl (const QString &attribUrl)
 
const QString & attributionUrl () const
 
void setMetadataUrl (const QString &metaUrl)
 
const QString & metadataUrl () const
 
void setMetadataUrlType (const QString &metaUrlType)
 
const QString & metadataUrlType () const
 
void setMetadataUrlFormat (const QString &metaUrlFormat)
 
const QString & metadataUrlFormat () const
 
void setBlendMode (const QPainter::CompositionMode &blendMode)
 Write blend mode for layer. More...
 
QPainter::CompositionMode blendMode () const
 Read blend mode for layer. More...
 
bool isValid ()
 
QString publicSource () const
 
const QString & source () const
 Returns the source for the layer. More...
 
virtual QStringList subLayers () const
 Returns the sublayers of this layer (Useful for providers that manage their own layers, such as WMS) More...
 
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) More...
 
virtual void setSubLayerVisibility (QString name, bool vis)
 Set the visibility of the given sublayer name. More...
 
bool readLayerXML (const QDomElement &layerElement)
 sets state from Dom document More...
 
bool writeLayerXML (QDomElement &layerElement, QDomDocument &document, QString relativeBasePath=QString::null)
 stores state in Dom node More...
 
void setCustomProperty (const QString &key, const QVariant &value)
 Set a custom property for layer. More...
 
QVariant customProperty (const QString &value, const QVariant &defaultValue=QVariant()) const
 Read a custom property from layer. More...
 
void removeCustomProperty (const QString &key)
 Remove a custom property from layer. More...
 
virtual Q_DECL_DEPRECATED QString lastErrorTitle ()
 
virtual Q_DECL_DEPRECATED QString lastError ()
 
virtual QgsError error () const
 Get current status error. More...
 
const
QgsCoordinateReferenceSystem
crs () const
 Returns layer's spatial reference system. More...
 
void setCrs (const QgsCoordinateReferenceSystem &srs, bool emitSignal=true)
 Sets layer's spatial reference system. More...
 
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) More...
 
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) More...
 
virtual bool loadNamedStyleFromDb (const QString &db, const QString &theURI, QString &qml)
 
virtual void exportNamedStyle (QDomDocument &doc, QString &errorMsg)
 Export the properties of this layer as named style in a QDomDocument. More...
 
virtual void exportSldStyle (QDomDocument &doc, QString &errorMsg)
 Export the properties of this layer as SLD style in a QDomDocument. More...
 
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) More...
 
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) More...
 
virtual QString saveSldStyle (const QString &theURI, bool &theResultFlag)
 
virtual QString loadSldStyle (const QString &theURI, bool &theResultFlag)
 
QUndoStack * undoStack ()
 Return pointer to layer's undo stack. More...
 
void setLegendUrl (const QString &legendUrl)
 
const QString & legendUrl () const
 
void setLegendUrlFormat (const QString &legendUrlFormat)
 
const QString & legendUrlFormat () const
 
Q_DECL_DEPRECATED QImage * cacheImage ()
 
Q_DECL_DEPRECATED void setCacheImage (QImage *)
 
virtual Q_DECL_DEPRECATED void onCacheImageDelete ()
 
void setLegend (QgsMapLayerLegend *legend)
 Assign a legend controller to the map layer. More...
 
QgsMapLayerLegendlegend () const
 Can be null. More...
 

Static Public Member Functions

static void drawVertexMarker (double x, double y, QPainter &p, QgsVectorLayer::VertexMarkerType type, int vertexSize)
 Draws a vertex symbol at (screen) coordinates x, y. More...
 
- Static Public Member Functions inherited from QgsMapLayer
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. More...
 
static QList< QgsMapLayer * > fromLayerDefinition (QDomDocument &document)
 Creates a new layer from a layer defininition document. More...
 
static QList< QgsMapLayer * > fromLayerDefinitionFile (const QString qlrfile)
 
static QString capitaliseLayerName (const QString &name)
 A convenience function to (un)capitalise the layer name. More...
 

Protected Slots

void invalidateSymbolCountedFlag ()
 

Protected Member Functions

void setExtent (const QgsRectangle &rect)
 Set the extent. More...
 
- Protected Member Functions inherited from QgsMapLayer
void setValid (bool valid)
 set whether layer is valid or not - should be used in constructor. More...
 
void readCustomProperties (const QDomNode &layerNode, const QString &keyStartsWith="")
 Read custom properties from project file. More...
 
void writeCustomProperties (QDomNode &layerNode, QDomDocument &doc) const
 Write custom properties to project file. More...
 
void connectNotify (const char *signal)
 debugging member - invoked when a connect() is made to this object More...
 
void appendError (const QgsErrorMessage &theMessage)
 Add error message. More...
 
void setError (const QgsError &theError)
 Set error message. More...
 

Friends

class QgsVectorLayerEditBuffer
 
class QgsVectorLayerFeatureSource
 

Additional Inherited Members

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

Detailed Description

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:

QString uri = "point?crs=epsg:4326&field=id:integer";
QgsVectorLayer *scratchLayer = new QgsVectorLayer(uri, "Scratch point layer", "memory");

The main data providers supported by QGIS are listed below.

Vector data providers

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:

An example url is "Point?crs=epsg:4326&field=id:integer&field=name:string(20)&index=yes"

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.

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.

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.

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.

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 1.0.0 server or a GML2 data file path. Examples are http://foobar/wfs or /foo/bar/file.gml

If a GML2 file path is provided the driver will attempt to read the schema from a file in the same directory with the same basename + “.xsd”. This xsd file must be in the same format as a WFS describe feature type response. If no xsd file is provide then the driver will attempt to guess the attribute types from the file.

In the case of a HTTP URL 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:

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:

-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.

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"

Grass data provider (grass)

Provider to display vector data in a GRASS GIS layer.

Constructor & Destructor Documentation

QgsVectorLayer::QgsVectorLayer ( QString  path = QString::null,
QString  baseName = QString::null,
QString  providerLib = QString::null,
bool  loadDefaultStyleFlag = true 
)

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.

Parameters
pathThe path or url of the parameter. Typically this encodes parameters used by the data provider as url query items.
baseNameThe name used to represent the layer in the legend
providerLibThe name of the data provider, eg "memory", "postgres"
loadDefaultStyleFlagwhether to load the default style
QgsVectorLayer::~QgsVectorLayer ( )
virtual

Destructor.

Member Function Documentation

QgsAttributeAction* QgsVectorLayer::actions ( )
inline
bool QgsVectorLayer::addAttribute ( const QgsField field)

add an attribute field (but does not commit it) returns true if the field was added

void QgsVectorLayer::addAttributeAlias ( int  attIndex,
QString  aliasString 
)

Sets an alias (a display name) for attributes to display in dialogs.

void QgsVectorLayer::addAttributeEditorWidget ( QgsAttributeEditorElement data)

Adds a tab (for the attribute editor form) holding groups and fields.

void QgsVectorLayer::addExpressionField ( const QString &  exp,
const QgsField fld 
)

Add a new field which is calculated by the expression specified.

Parameters
expThe expression which calculates the field
fldThe field to calculate
Note
added in 2.6
bool QgsVectorLayer::addFeature ( QgsFeature f,
bool  alsoUpdateExtent = true 
)

Adds a feature.

Parameters
ffeature to add
alsoUpdateExtentIf True, will also go to the effort of e.g. updating the extents.
Returns
True in case of success and False in case of error
bool QgsVectorLayer::addFeatures ( QgsFeatureList  features,
bool  makeSelected = true 
)

Insert a copy of the given features into the layer (but does not commit it)

bool QgsVectorLayer::addJoin ( const QgsVectorJoinInfo joinInfo)

Joins another vector layer to this layer.

Parameters
joinInfojoin object containing join layer id, target and source field
Note
since 2.6 returns bool indicating whether the join can be added
int QgsVectorLayer::addPart ( const QList< QgsPoint > &  ring)

Adds a new part polygon to a multipart feature.

Returns
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 QgsVectorLayer::addRing ( const QList< QgsPoint > &  ring)

Adds a ring to polygon/multipolygon features.

Returns
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 QgsVectorLayer::addTopologicalPoints ( QgsGeometry geom)

Adds topological points for every vertex of the geometry.

Parameters
geomthe geometry where each vertex is added to segments of other features
Note
geom is not going to be modified by the function
Returns
0 in case of success
int QgsVectorLayer::addTopologicalPoints ( const QgsPoint p)

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.

Parameters
pposition of the vertex
Returns
0 in case of success
QgsFeatureIds QgsVectorLayer::allFeatureIds ( )

Get all feature Ids.

QString QgsVectorLayer::annotationForm ( ) const
inline

get annotation form

bool QgsVectorLayer::applyNamedStyle ( QString  namedStyle,
QString  errorMsg 
)
virtual
void QgsVectorLayer::attributeAdded ( int  idx)
signal

Will be emitted, when a new attribute has been added to this vector layer.

Applies only to types QgsFields::OriginEdit and QgsFields::OriginProvider

Parameters
idxThe index of the new attribute
See also
updatedFields()
QString QgsVectorLayer::attributeAlias ( int  attributeIndex) const

Returns the alias of an attribute name or an empty string if there is no alias.

const QMap< QString, QString >& QgsVectorLayer::attributeAliases ( ) const
inline
void QgsVectorLayer::attributeDeleted ( int  idx)
signal

Will be emitted, when an attribute has been deleted from this vector layer.

Applies only to types QgsFields::OriginEdit and QgsFields::OriginProvider

Parameters
idxThe index of the deleted attribute
See also
updatedFields()
QString QgsVectorLayer::attributeDisplayName ( int  attributeIndex) const

Convenience function that returns the attribute alias if defined or the field name else.

QgsAttributeEditorElement * QgsVectorLayer::attributeEditorElementFromDomElement ( QDomElement &  elem,
QObject *  parent 
)

convert a saved attribute editor element into a AttributeEditor structure as it's used internally.

Parameters
elemthe DOM element
parentthe QObject which will own this object
QList< QgsAttributeEditorElement * > & QgsVectorLayer::attributeEditorElements ( )

Returns a list of tabs holding groups and fields.

void QgsVectorLayer::attributeValueChanged ( QgsFeatureId  fid,
int  idx,
const QVariant &   
)
signal
void QgsVectorLayer::beforeCommitChanges ( )
signal

Is emitted, before changes are commited to the data provider.

void QgsVectorLayer::beforeModifiedCheck ( ) const
signal

Is emitted, when layer is checked for modifications.

Use for last-minute additions

void QgsVectorLayer::beforeRollBack ( )
signal

Is emitted, before changes are rolled back.

void QgsVectorLayer::beginEditCommand ( QString  text)

Create edit command for undo/redo operations.

Parameters
texttext which is to be displayed in undo window
QgsRectangle QgsVectorLayer::boundingBoxOfSelected ( )

Returns the bounding box of the selected features.

If there is no selection, QgsRectangle(0,0,0,0) is returned

QgsGeometryCache* QgsVectorLayer::cache ( )
inline
Note
not available in python bindings
QString QgsVectorLayer::capabilitiesString ( ) const

Capabilities for this layer in a friendly format.

bool QgsVectorLayer::changeAttributeValue ( QgsFeatureId  fid,
int  field,
QVariant  value,
bool  emitSignal 
)

Changes an attribute value (but does not commit it)

Deprecated:
The emitSignal parameter is obsolete and not considered at the moment. It will be removed in future releases. Remove it to be prepared for the future. (Since 2.1)
bool QgsVectorLayer::changeAttributeValue ( QgsFeatureId  fid,
int  field,
const QVariant &  newValue,
const QVariant &  oldValue = QVariant() 
)

Changes an attribute value (but does not commit it)

Parameters
fidThe feature id of the feature to be changed
fieldThe index of the field to be updated
newValueThe value which will be assigned to the field
oldValueThe previous value to restore on undo (will otherwise be retrieved)
Returns
true in case of success
bool QgsVectorLayer::changeGeometry ( QgsFeatureId  fid,
QgsGeometry geom 
)

change feature's geometry

void QgsVectorLayer::checkJoinLayerRemove ( QString  theLayerId)
slot

Check if there is a join with a layer that will be removed.

void QgsVectorLayer::clearAttributeEditorWidgets ( )

Clears all the tabs for the attribute editor form.

bool QgsVectorLayer::commitChanges ( )

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.

const QStringList & QgsVectorLayer::commitErrors ( )
void QgsVectorLayer::committedAttributesAdded ( const QString &  layerId,
const QList< QgsField > &  addedAttributes 
)
signal
void QgsVectorLayer::committedAttributesDeleted ( const QString &  layerId,
const QgsAttributeList deletedAttributes 
)
signal

Signals emitted after committing changes.

void QgsVectorLayer::committedAttributeValuesChanges ( const QString &  layerId,
const QgsChangedAttributesMap changedAttributesValues 
)
signal
void QgsVectorLayer::committedFeaturesAdded ( const QString &  layerId,
const QgsFeatureList addedFeatures 
)
signal
void QgsVectorLayer::committedFeaturesRemoved ( const QString &  layerId,
const QgsFeatureIds deletedFeatureIds 
)
signal
void QgsVectorLayer::committedGeometriesChanges ( const QString &  layerId,
const QgsGeometryMap changedGeometries 
)
signal
bool QgsVectorLayer::countSymbolFeatures ( bool  showProgress = true)

Count features for symbols.

Feature counts may be get by featureCount( QgsSymbolV2*).

Parameters
showProgressshow progress dialog
Returns
true if calculated, false if failed or was canceled by user
void QgsVectorLayer::createJoinCaches ( )

Caches joined attributes if required (and not already done)

QgsMapLayerRenderer * QgsVectorLayer::createMapRenderer ( QgsRenderContext rendererContext)
virtual

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

Note
added in 2.4

Reimplemented from QgsMapLayer.

QString QgsVectorLayer::dataComment ( ) const

Returns a comment for the data in the layer.

QgsVectorDataProvider * QgsVectorLayer::dataProvider ( )

Returns the data provider.

const QgsVectorDataProvider * QgsVectorLayer::dataProvider ( ) const

Returns the data provider in a const-correct manner.

Note
not available in python bindings
QString QgsVectorLayer::dateFormat ( int  idx)

Access date format.

Deprecated:
Use setEditorWidgetV2Config() instead
bool QgsVectorLayer::deleteAttribute ( int  attr)

delete an attribute field (but does not commit it)

bool QgsVectorLayer::deleteAttributes ( QList< int >  attrs)

Deletes a list of attribute fields (but does not commit it)

Parameters
attrsthe indices of the attributes to delete
Returns
true if at least one attribute has been deleted
bool QgsVectorLayer::deleteFeature ( QgsFeatureId  fid)

delete a feature from the layer (but does not commit it)

bool QgsVectorLayer::deleteSelectedFeatures ( )

Deletes the selected features.

Returns
true in case of success and false otherwise
bool QgsVectorLayer::deleteVertex ( QgsFeatureId  atFeatureId,
int  atVertex 
)

Deletes a vertex from a feature.

void QgsVectorLayer::deselect ( const QgsFeatureId  featureId)
slot

Deselect feature by its ID.

Parameters
featureIdThe id of the feature to deselect
See also
deselect(QgsFeatureIds)
void QgsVectorLayer::deselect ( const QgsFeatureIds featureIds)
slot

Deselect features by their ID.

Parameters
featureIdsThe ids of the features to deselect
See also
deselect(QgsFeatureId)
void QgsVectorLayer::destroyEditCommand ( )

Destroy active command and reverts all changes in it.

const QgsDiagramLayerSettings* QgsVectorLayer::diagramLayerSettings ( ) const
inline
const QgsDiagramRendererV2* QgsVectorLayer::diagramRenderer ( ) const
inline
const QString QgsVectorLayer::displayExpression ( )

Get the preview expression, used to create a human readable preview string.

Uses QgsExpression

Returns
The expression which will be used to preview features for this layer
const QString QgsVectorLayer::displayField ( ) const

Returns the primary display field name used in the identify results dialog.

bool QgsVectorLayer::draw ( QgsRenderContext rendererContext)
virtual

Draws the layer.

Returns
false if an error occurred during drawing

Reimplemented from QgsMapLayer.

void QgsVectorLayer::drawLabels ( QgsRenderContext rendererContext)
virtual

Draws the layer labels using coordinate transformation.

Reimplemented from QgsMapLayer.

void QgsVectorLayer::drawVertexMarker ( double  x,
double  y,
QPainter &  p,
QgsVectorLayer::VertexMarkerType  type,
int  vertexSize 
)
static

Draws a vertex symbol at (screen) coordinates x, y.

(Useful to assist vertex editing.)

QgsVectorLayerEditBuffer* QgsVectorLayer::editBuffer ( )
inline

Buffer with uncommitted editing operations. Only valid after editing has been turned on.

void QgsVectorLayer::editCommandDestroyed ( )
signal

Signal emitted, whan an edit command is destroyed.

Note
This is not a rollback, it is only related to the current edit command. See beforeRollBack()
void QgsVectorLayer::editCommandEnded ( )
signal

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 beforeCommitChanges()
void QgsVectorLayer::editCommandStarted ( const QString &  text)
signal

Signal emitted when a new edit command has been started.

Parameters
textDescription for this edit command
QString QgsVectorLayer::editForm ( )

get edit form

QString QgsVectorLayer::editFormInit ( )

get python function for edit form initialization

void QgsVectorLayer::editingStarted ( )
signal

Is emitted, when editing on this layer has started.

void QgsVectorLayer::editingStopped ( )
signal

Is emitted, when edited changes successfully have been written to the data provider.

QgsVectorLayer::EditorLayout QgsVectorLayer::editorLayout ( )

get the active layout for the attribute editor for this layer

const QString QgsVectorLayer::editorWidgetV2 ( int  fieldIdx) const

Get the id for the editor widget used to represent the field at the given index.

Parameters
fieldIdxThe index of the field
Returns
The id for the editor widget or a NULL string if not applicable
const QString QgsVectorLayer::editorWidgetV2 ( const QString &  fieldName) const

Get the id for the editor widget used to represent the field at the given index.

Parameters
fieldNameThe name of the field
Returns
The id for the editor widget or a NULL string if not applicable
Note
python method name editorWidgetV2ByName
const QgsEditorWidgetConfig QgsVectorLayer::editorWidgetV2Config ( int  fieldIdx) const

Get the configuration for the editor widget used to represent the field at the given index.

Parameters
fieldIdxThe index of the field
Returns
The configuration for the editor widget or an empty config if the field does not exist
const QgsEditorWidgetConfig QgsVectorLayer::editorWidgetV2Config ( const QString &  fieldName) const

Get the configuration for the editor widget used to represent the field at the given index.

Parameters
fieldNameThe name of the field
Returns
The configuration for the editor widget or an empty config if the field does not exist
Note
python method name is editorWidgetV2ConfigByName
QgsVectorLayer::EditType QgsVectorLayer::editType ( int  idx)

Get edit type.

Deprecated:
Use editorWidgetV2() instead
void QgsVectorLayer::enableLabels ( bool  on)

Set labels on.

void QgsVectorLayer::endEditCommand ( )

Finish edit command and add it to undo/redo stack.

const QSet<QString>& QgsVectorLayer::excludeAttributesWFS ( ) const
inline
const QSet<QString>& QgsVectorLayer::excludeAttributesWMS ( ) const
inline
QgsRectangle QgsVectorLayer::extent ( )
virtual

Return the extent of the layer as a QRect.

Reimplemented from QgsMapLayer.

void QgsVectorLayer::featureAdded ( QgsFeatureId  fid)
signal
QPainter::CompositionMode QgsVectorLayer::featureBlendMode ( ) const

Read blend mode for layer.

void QgsVectorLayer::featureBlendModeChanged ( const QPainter::CompositionMode &  blendMode)
signal

Signal emitted when setFeatureBlendMode() is called.

long QgsVectorLayer::featureCount ( ) const
virtual

Number of features in the layer.

This is necessary if features are added/deleted or the layer has been subsetted. If the data provider chooses not to support this feature, the total number of features can be returned.

Returns
long containing number of features
long QgsVectorLayer::featureCount ( QgsSymbolV2 symbol)

Number of features rendered with specified symbol.

Features must be first calculated by countSymbolFeatures()

Parameters
symbolthe symbol
Returns
number of features rendered by symbol or -1 if failed or counts are not available
void QgsVectorLayer::featureDeleted ( QgsFeatureId  fid)
signal
QgsVectorLayer::FeatureFormSuppress QgsVectorLayer::featureFormSuppress ( ) const
inline

Type of feature form pop-up suppression after feature creation (overrides app setting)

Note
added in 2.1
bool QgsVectorLayer::fieldEditable ( int  idx)

is edit widget editable

int QgsVectorLayer::fieldNameIndex ( const QString &  fieldName) const

Returns the index of a field name or -1 if the field does not exist.

void QgsVectorLayer::geometryChanged ( QgsFeatureId  fid,
QgsGeometry geom 
)
signal
QGis::GeometryType QgsVectorLayer::geometryType ( ) const

Returns point, line or polygon.

QgsFeatureIterator QgsVectorLayer::getFeatures ( const QgsFeatureRequest request = QgsFeatureRequest())

Query the provider for features specified in request.

QString QgsVectorLayer::getStyleFromDatabase ( QString  styleId,
QString &  msgError 
)
virtual

Will return the named style corresponding to style id provided.

bool QgsVectorLayer::hasGeometryType ( ) const

Returns true if this is a geometry layer and false in case of NoGeometry (table only) or UnknownGeometry.

bool QgsVectorLayer::hasLabelsEnabled ( void  ) const

Label is on.

int QgsVectorLayer::insertSegmentVerticesForSnap ( const QList< QgsSnappingResult > &  snapResults)

Inserts vertices to the snapped segments.

This is useful for topological editing if snap to segment is enabled.

Parameters
snapResultsresults collected from the snapping operation
Returns
0 in case of success
bool QgsVectorLayer::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.

void QgsVectorLayer::invalidateSymbolCountedFlag ( )
protectedslot
void QgsVectorLayer::invertSelection ( )

Select not selected features and deselect selected ones.

void QgsVectorLayer::invertSelectionInRectangle ( QgsRectangle rect)

Invert selection of features found within the search rectangle (in layer's coordinates)

Parameters
rectThe rectangle in which the selection of features will be inverted
See also
invertSelection()
bool QgsVectorLayer::isEditable ( ) const
virtual

Returns true if the provider is in editing mode.

Reimplemented from QgsMapLayer.

bool QgsVectorLayer::isModified ( ) const
virtual

Returns true if the provider has been modified since the last commit.

bool QgsVectorLayer::isReadOnly ( ) const
virtual

Returns true if the provider is in read-only mode.

QgsLabel * QgsVectorLayer::label ( )

Get the label object associated with this layer.

const QgsLabel * QgsVectorLayer::label ( ) const
void QgsVectorLayer::labelingFontNotFound ( QgsVectorLayer layer,
const QString &  fontfamily 
)
signal

Emitted when the font family defined for labeling layer is not found on system.

bool QgsVectorLayer::labelOnTop ( int  idx)

label widget on top

void QgsVectorLayer::layerDeleted ( )
signal
void QgsVectorLayer::layerModified ( )
signal

This signal is emitted when modifications has been done on layer.

int QgsVectorLayer::layerTransparency ( ) const

Read transparency for layer.

void QgsVectorLayer::layerTransparencyChanged ( int  layerTransparency)
signal

Signal emitted when setLayerTransparency() is called.

int QgsVectorLayer::listStylesInDatabase ( QStringList &  ids,
QStringList &  names,
QStringList &  descriptions,
QString &  msgError 
)
virtual

Lists all the style in db split into related to the layer and not related to.

Parameters
idsthe list in which will be stored the style db ids
namesthe list in which will be stored the style names
descriptionsthe list in which will be stored the style descriptions
msgError
Returns
the number of styles related to current layer
QString QgsVectorLayer::loadNamedStyle ( const QString &  theURI,
bool &  theResultFlag,
bool  loadFromLocalDb 
)
virtual

Load a named style from file/local db/datasource db.

Parameters
theURIthe URI of the style or the URI of the layer
theResultFlagwill be set to true if a named style is correctly loaded
loadFromLocalDbif true forces to load from local db instead of datasource one
QString QgsVectorLayer::loadNamedStyle ( const QString &  theURI,
bool &  theResultFlag 
)
virtual

Calls loadNamedStyle( theURI, theResultFlag, false ); Retained for backward compatibility.

Reimplemented from QgsMapLayer.

QVariant QgsVectorLayer::maximumValue ( int  index)

Returns maximum value for an attribute column or invalid variant in case of error.

QString QgsVectorLayer::metadata ( )
virtual

Obtain Metadata for this layer.

Reimplemented from QgsMapLayer.

QVariant QgsVectorLayer::minimumValue ( int  index)

Returns minimum value for an attribute column or invalid variant in case of error.

void QgsVectorLayer::modifySelection ( QgsFeatureIds  selectIds,
QgsFeatureIds  deselectIds 
)

Modifies the current selection on this layer.

Parameters
selectIdsSelect these ids
deselectIdsDeselect these ids
See also
select(QgsFeatureIds)
select(QgsFeatureId)
deselect(QgsFeatureIds)
deselect(QgsFeatureId)
bool QgsVectorLayer::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.

QgsAttributeList QgsVectorLayer::pendingAllAttributesList ( )

returns list of attributes

int QgsVectorLayer::pendingFeatureCount ( )

returns feature count after commit

const QgsFields & QgsVectorLayer::pendingFields ( ) const

returns field list in the to-be-committed state

QgsAttributeList QgsVectorLayer::pendingPkAttributesList ( )

returns list of attribute making up the primary key

QString QgsVectorLayer::providerType ( ) const

Return the provider type for this layer.

QgsVectorLayer::RangeData QgsVectorLayer::range ( int  idx)

Access range widget config data.

Deprecated:
Use editorWidgetV2Config() instead
void QgsVectorLayer::readCustomSymbology ( const QDomElement &  element,
QString &  errorMessage 
)
signal

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.

Parameters
elementThe XML layer style element.
errorMessageWrite error messages into this string.
bool QgsVectorLayer::readSld ( const QDomNode &  node,
QString &  errorMessage 
)
virtual

Reimplemented from QgsMapLayer.

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

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

Parameters
nodenode that will contain the symbology definition for this layer.
errorMessagereference to string that will be updated with any error messages
Returns
true in case of success.

Implements QgsMapLayer.

bool QgsVectorLayer::readXml ( const QDomNode &  layer_node)
virtual

reads vector layer specific state from project file Dom node.

Note
Called by QgsMapLayer::readXML().

Reimplemented from QgsMapLayer.

QList< QgsRelation > QgsVectorLayer::referencingRelations ( int  idx)

Get relations, where the foreign key is on this layer.

Parameters
idxOnly get relations, where idx forms part of the foreign key
Returns
A list of relations
void QgsVectorLayer::reload ( )
virtual

Synchronises with changes in the datasource.

Reimplemented from QgsMapLayer.

void QgsVectorLayer::remAttributeAlias ( int  attIndex)

Removes an alias (a display name) for attributes to display in dialogs.

void QgsVectorLayer::removeExpressionField ( int  index)

Remove an expression field.

Parameters
indexThe index of the field
Note
added in 2.6
void QgsVectorLayer::removeJoin ( const QString &  joinLayerId)

Removes a vector layer join.

int QgsVectorLayer::removePolygonIntersections ( QgsGeometry geom,
QgsFeatureIds  ignoreFeatures = QgsFeatureIds() 
)

Changes the specified geometry such that it has no intersections with other polygon (or multipolygon) geometries in this vector layer.

Parameters
geomgeometry to modify
ignoreFeatureslist of feature ids where intersections should be ignored
Returns
0 in case of success
Deprecated:
since 2.2 - not being used for "avoid intersections" functionality anymore
void QgsVectorLayer::removeSelection ( )
slot
QgsFeatureRendererV2 * QgsVectorLayer::rendererV2 ( )

Return renderer V2.

bool QgsVectorLayer::rollBack ( bool  deleteBuffer = true)

Stop editing and discard the edits.

Parameters
deleteBufferwhether to delete editing buffer
void QgsVectorLayer::saveLayerToProject ( )
signal
void QgsVectorLayer::saveStyleToDatabase ( QString  name,
QString  description,
bool  useAsDefault,
QString  uiFileContent,
QString &  msgError 
)
virtual

Save named and sld style of the layer to the style table in the db.

Parameters
name
description
useAsDefault
uiFileContent
msgError
void QgsVectorLayer::select ( QgsRectangle rect,
bool  addToSelection 
)

Select features found within the search rectangle (in layer's coordinates)

Parameters
rectThe search rectangle
addToSelectionIf set to true will not clear before selecting
See also
invertSelectionInRectangle(QgsRectangle & rect)
void QgsVectorLayer::select ( const QgsFeatureId featureId)
slot

Select feature by its ID.

Parameters
featureIdThe id of the feature to select
See also
select(QgsFeatureIds)
void QgsVectorLayer::select ( const QgsFeatureIds featureIds)
slot

Select features by their ID.

Parameters
featureIdsThe ids of the features to select
See also
select(QgsFeatureId)
void QgsVectorLayer::selectAll ( )

Select all the features.

int QgsVectorLayer::selectedFeatureCount ( )

The number of features that are selected in this layer.

Returns
See description
QgsFeatureList QgsVectorLayer::selectedFeatures ( )

Get a copy of the user-selected features.

Returns
A list of QgsFeature 's
See also
selectedFeaturesIds()
selectedFeaturesIterator() which is more memory friendly when handling large selections
const QgsFeatureIds & QgsVectorLayer::selectedFeaturesIds ( ) const

Return reference to identifiers of selected features.

Returns
A list of QgsFeatureId 's
See also
selectedFeatures()
QgsFeatureIterator QgsVectorLayer::selectedFeaturesIterator ( QgsFeatureRequest  request = QgsFeatureRequest())

Get an iterator of the selected features.

Parameters
requestYou may specify a request, e.g. to limit the set of requested attributes. Any filter on the request will be discarded.
Returns
Iterator over the selected features
See also
selectedFeaturesIds()
selectedFeatures()
void QgsVectorLayer::selectionChanged ( const QgsFeatureIds  selected,
const QgsFeatureIds  deselected,
const bool  clearAndSelect 
)
signal

This signal is emitted when selection was changed.

Parameters
selectedNewly selected feature ids
deselectedIds of all features which have previously been selected but are not any more
clearAndSelectIn case this is set to true, the old selection was dismissed and the new selection corresponds to selected
void QgsVectorLayer::selectionChanged ( )
signal

This signal is emitted when selection was changed.

void QgsVectorLayer::setAnnotationForm ( const QString &  ui)

set annotation form for layer

void QgsVectorLayer::setCheckedState ( int  idx,
QString  checked,
QString  notChecked 
)

Set string representing 'true' for a checkbox.

Deprecated:
Use setEditorWidgetV2Config() instead
void QgsVectorLayer::setCoordinateSystem ( )

Setup the coordinate system transformation for the layer.

void QgsVectorLayer::setDiagramLayerSettings ( const QgsDiagramLayerSettings s)
void QgsVectorLayer::setDiagramRenderer ( QgsDiagramRendererV2 r)

Sets diagram rendering object (takes ownership)

void QgsVectorLayer::setDisplayExpression ( const QString &  displayExpression)

Set the preview expression, used to create a human readable preview string.

Used e.g. in the attribute table feature list. Uses QgsExpression.

Parameters
displayExpressionThe expression which will be used to preview features for this layer
void QgsVectorLayer::setDisplayField ( QString  fldName = "")

Set the primary display field to be used in the identify results dialog.

sets the preferred display field based on some fuzzy logic

void QgsVectorLayer::setEditForm ( QString  ui)

set edit form

void QgsVectorLayer::setEditFormInit ( QString  function)

set python function for edit form initialization

void QgsVectorLayer::setEditorLayout ( EditorLayout  editorLayout)

set the active layout for the attribute editor for this layer

void QgsVectorLayer::setEditorWidgetV2 ( int  attrIdx,
const QString &  widgetType 
)

Set the editor widget type for a field.

QGIS ships the following widget types, additional types may be available depending on plugins.

Parameters
attrIdxIndex of the field
widgetTypeType id of the editor widget to use
void QgsVectorLayer::setEditorWidgetV2Config ( int  attrIdx,
const QgsEditorWidgetConfig config 
)

Set the editor widget config for a field.

Python: Will accept a map.

Example:

1 layer.setEditorWidgetV2Config( 1, { 'Layer': 'otherlayerid_1234', 'Key': 'Keyfield', 'Value': 'ValueField' } )
Parameters
attrIdxIndex of the field
configThe config to set for this field
See also
setEditorWidgetV2() for a list of widgets and choose the widget to see the available options.
void QgsVectorLayer::setEditType ( int  idx,
EditType  edit 
)

Get edit type.

Deprecated:
Use setEditorWidgetV2() instead
void QgsVectorLayer::setExcludeAttributesWFS ( const QSet< QString > &  att)
inline
void QgsVectorLayer::setExcludeAttributesWMS ( const QSet< QString > &  att)
inline
void QgsVectorLayer::setExtent ( const QgsRectangle rect)
protectedvirtual

Set the extent.

Reimplemented from QgsMapLayer.

void QgsVectorLayer::setFeatureBlendMode ( const QPainter::CompositionMode &  blendMode)

Write blend mode for features.

void QgsVectorLayer::setFeatureFormSuppress ( QgsVectorLayer::FeatureFormSuppress  s)
inline

Set type of feature form pop-up suppression after feature creation (overrides app setting)

Note
added in 2.1
void QgsVectorLayer::setFieldEditable ( int  idx,
bool  editable 
)

set edit widget editable

void QgsVectorLayer::setLabelOnTop ( int  idx,
bool  onTop 
)

label widget on top

void QgsVectorLayer::setLayerTransparency ( int  layerTransparency)

Write transparency for layer.

void QgsVectorLayer::setProviderEncoding ( const QString &  encoding)

Sets the textencoding of the data provider.

bool QgsVectorLayer::setReadOnly ( bool  readonly = true)

Make layer read-only (editing disabled) or not.

Returns
false if the layer is in editing yet
void QgsVectorLayer::setRendererV2 ( QgsFeatureRendererV2 r)

Set renderer V2.

void QgsVectorLayer::setSelectedFeatures ( const QgsFeatureIds ids)

Change selection to the new set of features.

Dismisses the current selection. Will emit the selectionChanged( QgsFeatureIds, QgsFeatureIds, bool ) signal with the clearAndSelect flag set.

Parameters
idsThe ids which will be the new selection
void QgsVectorLayer::setSimplifyMethod ( const QgsVectorSimplifyMethod simplifyMethod)
inline

Set the simplification settings for fast rendering of features.

Note
added in 2.2
bool QgsVectorLayer::setSubsetString ( QString  subset)
virtual

Set the string (typically sql) used to define a subset of the layer.

Parameters
subsetThe subset string. This may be the where clause of a sql statement or other defintion string specific to the underlying dataprovider and data store.
Returns
true, when setting the subset string was successful, false otherwise
bool QgsVectorLayer::simplifyDrawingCanbeApplied ( const QgsRenderContext renderContext,
QgsVectorSimplifyMethod::SimplifyHint  simplifyHint 
) 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!
added in 2.2
const QgsVectorSimplifyMethod& QgsVectorLayer::simplifyMethod ( ) const
inline

Returns the simplification settings for fast rendering of features.

Note
added in 2.2
bool QgsVectorLayer::snapPoint ( QgsPoint point,
double  tolerance 
)

Snaps a point to the closest vertex if there is one within the snapping tolerance.

Parameters
pointThe 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.
toleranceThe snapping tolerance
Returns
true if the point has been snapped, false if no vertex within search tolerance
int QgsVectorLayer::snapWithContext ( const QgsPoint startPoint,
double  snappingTolerance,
QMultiMap< double, QgsSnappingResult > &  snappingResults,
QgsSnapper::SnappingType  snap_to 
)

Snaps to segment or vertex within given tolerance.

Parameters
startPointpoint to snap (in layer coordinates)
snappingTolerancedistance tolerance for snapping
snappingResultssnapping results. Key is the distance between startPoint and snapping target
snap_toto segment / to vertex
Returns
0 in case of success
int QgsVectorLayer::splitFeatures ( const QList< QgsPoint > &  splitLine,
bool  topologicalEditing = false 
)

Splits features cut by the given line.

Parameters
splitLineline that splits the layer features
topologicalEditingtrue if topological editing is enabled
Returns
0 in case of success, 4 if there is a selection but no feature split
int QgsVectorLayer::splitParts ( const QList< QgsPoint > &  splitLine,
bool  topologicalEditing = false 
)

Splits parts cut by the given line.

Parameters
splitLineline that splits the layer features
topologicalEditingtrue if topological editing is enabled
Returns
0 in case of success, 4 if there is a selection but no feature split
bool QgsVectorLayer::startEditing ( )

Make layer editable.

QString QgsVectorLayer::storageType ( ) const

Returns the permanent storage type for this layer as a friendly name.

QString QgsVectorLayer::subsetString ( )
virtual

Get the string (typically sql) used to define a subset of the layer.

Returns
The subset string or QString::null if not implemented by the provider
int QgsVectorLayer::translateFeature ( QgsFeatureId  featureId,
double  dx,
double  dy 
)

Translates feature by dx, dy.

Parameters
featureIdid of the feature to translate
dxtranslation of x-coordinate
dytranslation of y-coordinate
Returns
0 in case of success
void QgsVectorLayer::uniqueValues ( int  index,
QList< QVariant > &  uniqueValues,
int  limit = -1 
)

Returns unique values for column.

Parameters
indexcolumn index for attribute
uniqueValuesout: result list
limitmaximum number of values to return (-1 if unlimited)
void QgsVectorLayer::updatedFields ( )
signal

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 QgsVectorLayer::updateExtents ( )
virtualslot

Update the extents for the layer.

This is necessary if features are added/deleted or the layer has been subsetted.

bool QgsVectorLayer::updateFeature ( QgsFeature f)

Updates an existing feature.

This method needs to query the datasource on every call. Consider using changeAttributeValue() or changeGeometry() instead.

Parameters
fFeature to update
Returns
True in case of success and False in case of error
void QgsVectorLayer::updateFields ( )

Assembles mUpdatedFields considering provider fields, joined fields and added fields.

QMap< QString, QVariant > QgsVectorLayer::valueMap ( int  idx)

Access value map.

Deprecated:
Use editorWidgetV2Config() instead
QgsVectorLayer::ValueRelationData QgsVectorLayer::valueRelation ( int  idx)

Access value relation widget data.

const QList< QgsVectorJoinInfo > & QgsVectorLayer::vectorJoins ( ) const
QSize QgsVectorLayer::widgetSize ( int  idx)

Access widget size for photo and webview widget.

Deprecated:
Use setEditorWidgetV2Config() instead
QGis::WkbType QgsVectorLayer::wkbType ( ) const

Returns the WKBType or WKBUnknown in case of error.

void QgsVectorLayer::writeCustomSymbology ( QDomElement &  element,
QDomDocument &  doc,
QString &  errorMessage 
) const
signal

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.

Parameters
elementThe XML element where you can add additional style information to.
docThe XML document that you can use to create new XML nodes.
errorMessageWrite error messages into this string.
bool QgsVectorLayer::writeSld ( QDomNode &  node,
QDomDocument &  doc,
QString &  errorMessage 
) const
bool QgsVectorLayer::writeSymbology ( QDomNode &  node,
QDomDocument &  doc,
QString &  errorMessage 
) const
virtual

Write the symbology for the layer into the docment provided.

Parameters
nodethe node that will have the style element added to it.
docthe document that will have the QDomNode added.
errorMessagereference to string that will be updated with any error messages
Returns
true in case of success.

Implements QgsMapLayer.

bool QgsVectorLayer::writeXml ( QDomNode &  layer_node,
QDomDocument &  doc 
)
virtual

write vector layer specific state to project file Dom node.

Note
Called by QgsMapLayer::writeXML().

Reimplemented from QgsMapLayer.

Friends And Related Function Documentation

friend class QgsVectorLayerEditBuffer
friend
friend class QgsVectorLayerFeatureSource
friend

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