QGIS/src/core/qgsvectorlayer.h
2008-12-08 17:02:01 +00:00

645 lines
23 KiB
C++

/***************************************************************************
qgsvectorlayer.h - description
-------------------
begin : Oct 29, 2003
copyright : (C) 2003 by Gary E.Sherman
email : sherman at mrcc.com
***************************************************************************/
/***************************************************************************
* *
* This program is free software; you can redistribute it and/or modify *
* it under the terms of the GNU General Public License as published by *
* the Free Software Foundation; either version 2 of the License, or *
* (at your option) any later version. *
* *
***************************************************************************/
/* $Id$ */
#ifndef QGSVECTORLAYER_H
#define QGSVECTORLAYER_H
#include <QMap>
#include <QSet>
#include <QList>
#include <QStringList>
#include "qgis.h"
#include "qgsmaplayer.h"
#include "qgsfeature.h"
#include "qgssnapper.h"
#include "qgsfeature.h"
#include "qgsfield.h"
class QPainter;
class QImage;
class QgsAttributeAction;
class QgsCoordinateTransform;
class QgsGeometry;
class QgsGeometryVertexIndex;
class QgsMapToPixel;
class QgsLabel;
class QgsRectangle;
class QgsRenderer;
class QgsVectorDataProvider;
class QgsGeometry;
class QgsRectangle;
typedef QList<int> QgsAttributeList;
typedef QSet<int> QgsFeatureIds;
typedef QSet<int> QgsAttributeIds;
/** \ingroup core
* Vector layer backed by a data source provider.
*/
class CORE_EXPORT QgsVectorLayer : public QgsMapLayer
{
Q_OBJECT
public:
enum EditType
{
LineEdit,
UniqueValues,
UniqueValuesEditable,
ValueMap,
Classification,
EditRange,
SliderRange,
FileName
};
struct RangeData
{
RangeData() {}
RangeData( QVariant theMin, QVariant theMax, QVariant theStep )
: mMin( theMin ), mMax( theMax ), mStep( theStep ) {}
QVariant mMin;
QVariant mMax;
QVariant mStep;
};
/** Constructor */
QgsVectorLayer( QString path = 0, QString baseName = 0,
QString providerLib = 0, 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;
/** Set the primary display field to be used in the identify results dialog */
void setDisplayField( QString fldName = 0 );
/** Returns the primary display field name used in the identify results dialog */
const QString displayField() const;
/** Returns the data provider */
QgsVectorDataProvider* dataProvider();
/** Returns the data provider in a const-correct manner */
const QgsVectorDataProvider* dataProvider() const;
/** Sets the textencoding of the data provider */
void setProviderEncoding( const QString& encoding );
/** Setup the coordinate system tranformation for the layer */
void setCoordinateSystem();
/** Get the label object associated with this layer */
QgsLabel *label();
const QgsLabel *label() const;
QgsAttributeAction* actions() { return mActions; }
/** The number of features that are selected in this layer */
int selectedFeatureCount();
/** Select features found within the search rectangle (in layer's coordinates) */
void select( QgsRectangle & rect, bool lock );
/** Select not selected features and deselect selected ones */
void invertSelection();
/** Invert selection of features found within the search rectangle (in layer's coordinates) */
void invertSelectionInRectangle( QgsRectangle & rect);
/** Get a copy of the user-selected features */
QgsFeatureList selectedFeatures();
/** Return reference to identifiers of selected features */
const QgsFeatureIds& selectedFeaturesIds() const;
/** Change selection to the new set of features */
void setSelectedFeatures( const QgsFeatureIds& ids );
/** Returns the bounding box of the selected features. If there is no selection, QgsRectangle(0,0,0,0) is returned */
QgsRectangle boundingBoxOfSelected();
/** Copies the symbology settings from another layer. Returns true in case of success */
bool copySymbologySettings( const QgsMapLayer& other );
/** Returns true if this layer can be in the same symbology group with another layer */
bool hasCompatibleSymbology( const QgsMapLayer& other ) const;
/** Returns a pointer to the renderer */
const QgsRenderer* renderer() const;
/** Sets the renderer. If a renderer is already present, it is deleted */
void setRenderer( QgsRenderer * r );
/** Returns point, line or polygon */
QGis::GeometryType geometryType() const;
/**Returns the WKBType or WKBUnknown in case of error*/
QGis::WkbType 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( 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 );
/** Read the symbology for the current layer from the Dom node supplied.
* @param QDomNode 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 );
/** Write the symbology for the layer into the docment provided.
* @param QDomNode the node that will have the style element added to it.
* @param QDomDocument 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&, QDomDocument& doc, QString& errorMessage ) const;
/**
* 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.
* @return long containing number of features
*/
virtual long featureCount() const;
/** Update the feature count
* @return long containing the number of features in the datasource
*/
virtual long updateFeatureCount() const;
/**
* 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 defintion string specific to the underlying dataprovider
* and data store.
*/
virtual void setSubsetString( 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();
void select( QgsAttributeList fetchAttributes,
QgsRectangle rect = QgsRectangle(),
bool fetchGeometry = true,
bool useIntersect = false );
bool nextFeature( QgsFeature& feature );
/**Gets the feature at the given feature id. Considers the changed, added, deleted and permanent features
@return true in case of success*/
bool featureAtId( int featureId, QgsFeature &f, bool fetchGeometries = true, bool fetchAttributes = true );
/** Adds a feature
@param lastFeatureInBatch 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& f, bool alsoUpdateExtent = TRUE );
/** 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, int 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, int atFeatureId, int atVertex );
/** Deletes a vertex from a feature
*/
bool deleteVertex( int atFeatureId, int atVertex );
/** Deletes the selected features
* @return true in case of success and false otherwise
*/
bool deleteSelectedFeatures();
/**Adds a ring to polygon/multipolygon features
@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*/
int addRing( const QList<QgsPoint>& ring );
/**Adds a new island polygon to a multipolygon feature
@return
0 in case of success,
1 if selected feature is not multipolygon,
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*/
int addIsland( const QList<QgsPoint>& ring );
/**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( int featureId, double dx, double dy );
/**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 );
/**Changes the specified geometry such that it has no intersections with other
polygon (or multipolygon) geometries in this vector layer
@param geom geometry to modify
@return 0 in case of success*/
int removePolygonIntersections( QgsGeometry* geom );
/**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( 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 usefull 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 );
/** Set labels on */
void enableLabels( bool on );
/** Label is on */
bool hasLabelsEnabled( void ) const;
/** Returns true if the provider is in editing mode */
virtual bool isEditable() 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 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,
QgsSnapper::SnappingType snap_to );
/** Draws the layer
* @return FALSE if an error occurred during drawing
*/
bool draw( QgsRenderContext& rendererContext );
/** Draws the layer labels using coordinate transformation */
void drawLabels( QgsRenderContext& rendererContext );
/** returns field list in the to-be-committed state */
const QgsFieldMap &pendingFields() const;
/** returns list of attributes */
QgsAttributeList pendingAllAttributesList();
/** returns feature count after commit */
int pendingFeatureCount();
/** Sets whether some features are modified or not */
void setModified( bool modified = TRUE, bool onlyGeometryWasModified = FALSE );
/** Make layer editable */
bool startEditing();
/** changed an attribute value (but does not commit it */
bool changeAttributeValue( int fid, int field, QVariant value, bool emitSignal = true );
/** add an attribute field (but does not commit it)
returns the field index or -1 in case of failure */
bool addAttribute( QString name, QString type );
/** delete an attribute field (but does not commit it) */
bool deleteAttribute( int attr );
/** Insert a copy of the given features into the layer (but does not commit it) */
bool addFeatures( QgsFeatureList features, bool makeSelected = TRUE );
/** delete a feature from the layer (but does not commit it) */
bool deleteFeature( int fid );
/**
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.
*/
bool commitChanges();
const QStringList &commitErrors();
/** Stop editing and discard the edits */
bool rollBack();
/**get edit type*/
EditType editType( int idx );
/**set edit type*/
void setEditType( int idx, EditType edit );
/**access value map*/
QMap<QString, QVariant> &valueMap( int idx );
/**access range */
RangeData &range( int idx );
public slots:
/** Select feature by its ID, optionally emit signal selectionChanged() */
void select( int featureId, bool emitSignal = TRUE );
/** Deselect feature by its ID, optionally emit signal selectionChanged() */
void deselect( int featureId, bool emitSignal = TRUE );
/** Clear selection */
void removeSelection( bool emitSignal = TRUE );
void triggerRepaint();
/** Update the extents for the layer. This is necessary if features are
* added/deleted or the layer has been subsetted.
*/
virtual void updateExtents();
signals:
/** This signal is emited when selection was changed */
void selectionChanged();
/** This signal is emitted when modifications has been done on layer */
void layerModified( bool onlyGeometry );
void editingStarted();
void editingStopped();
void attributeAdded( int idx );
void attributeDeleted( int idx );
void featureDeleted( int fid );
void layerDeleted();
void attributeValueChanged( int fid, int idx, const QVariant & );
private: // Private methods
enum VertexMarkerType
{
SemiTransparentCircle,
Cross
};
/** vector layers are not copyable */
QgsVectorLayer( QgsVectorLayer const & rhs );
/** vector layers are not copyable */
QgsVectorLayer & operator=( QgsVectorLayer const & rhs );
/** bind layer to a specific data provider
@param provider should be "postgres", "ogr", or ??
@todo XXX should this return bool? Throw exceptions?
*/
bool setDataProvider( QString const & provider );
/** Draws features. May cause projections exceptions to be generated
* (i.e., code that calls this function needs to catch them)
*/
void drawFeature( QPainter* p,
QgsFeature& fet,
const QgsMapToPixel* cXf,
const QgsCoordinateTransform* ct,
QImage* marker,
double widthScale,
double markerScaleFactor,
bool drawingToEditingCanvas );
/** Convenience function to transform the given point */
void transformPoint( double& x, double& y,
const QgsMapToPixel* mtp, const QgsCoordinateTransform* ct );
void transformPoints( std::vector<double>& x, std::vector<double>& y, std::vector<double>& z,
const QgsMapToPixel* mtp, const QgsCoordinateTransform* ct );
/** Draw the linestring as given in the WKB format. Returns a pointer
* to the byte after the end of the line string binary data stream (WKB).
*/
unsigned char *drawLineString( unsigned char *WKBlinestring,
QPainter *p,
const QgsMapToPixel *mtp,
const QgsCoordinateTransform *ct,
bool drawingToEditingCanvas );
/** Draw the polygon as given in the WKB format. Returns a pointer to
* the byte after the end of the polygon binary data stream (WKB).
*/
unsigned char *drawPolygon( unsigned char *WKBpolygon,
QPainter *p,
const QgsMapToPixel *mtp,
const QgsCoordinateTransform *ct,
bool drawingToEditingCanvas );
/** Goes through all features and finds a free id (e.g. to give it temporarily to a not-commited feature) */
int findFreeId();
/**Deletes the geometries in mCachedGeometries*/
void deleteCachedGeometries();
/** Draws a vertex symbol at (screen) coordinates x, y. (Useful to assist vertex editing.) */
void drawVertexMarker( int x, int y, QPainter& p, QgsVectorLayer::VertexMarkerType type );
/**Snaps to a geometry and adds the result to the multimap if it is within the snapping result
@param startPoint start point of the snap
@param geom geometry to snap
@param sqrSnappingTolerance squared search tolerance of the snap
@param snappingResult list to which the result is appended
@param snap_to snap to vertex or to segment
*/
void snapToGeometry( const QgsPoint& startPoint, int featureId, QgsGeometry* geom, double sqrSnappingTolerance,
QMultiMap<double, QgsSnappingResult>& snappingResults, QgsSnapper::SnappingType snap_to ) const;
/**Little helper function that gives bounding box from a list of points.
@return 0 in case of success*/
int boundingBoxFromPointList( const QList<QgsPoint>& list, double& xmin, double& ymin, double& xmax, double& ymax ) const;
/**Reads vertex marker type from settings*/
QgsVectorLayer::VertexMarkerType currentVertexMarkerType();
/**Update feature with uncommited attribute updates*/
void updateFeatureAttributes( QgsFeature &f );
/**Update feature with uncommited geometry updates*/
void updateFeatureGeometry( QgsFeature &f );
private: // Private attributes
/** Update threshold for drawing features as they are read. A value of zero indicates
* that no features will be drawn until all have been read
*/
int mUpdateThreshold;
/** Pointer to data provider derived from the abastract base class QgsDataProvider */
QgsVectorDataProvider *mDataProvider;
/** index of the primary label field */
QString mDisplayField;
/** Data provider key */
QString mProviderKey;
/** The user-defined actions that are accessed from the Identify Results dialog box */
QgsAttributeAction* mActions;
/** Flag indicating whether the layer is in editing mode or not */
bool mEditable;
/** Flag indicating whether the layer has been modified since the last commit */
bool mModified;
/** cache of the committed geometries retrieved *for the current display* */
QgsGeometryMap mCachedGeometries;
/** Set holding the feature IDs that are activated. Note that if a feature
subsequently gets deleted (i.e. by its addition to mDeletedFeatureIds),
it always needs to be removed from mSelectedFeatureIds as well.
*/
QgsFeatureIds mSelectedFeatureIds;
/** Deleted feature IDs which are not commited. Note a feature can be added and then deleted
again before the change is committed - in that case the added feature would be removed
from mAddedFeatures only and *not* entered here.
*/
QgsFeatureIds mDeletedFeatureIds;
/** New features which are not commited. Note a feature can be added and then changed,
therefore the details here can be overridden by mChangedAttributeValues and mChangedGeometries.
*/
QgsFeatureList mAddedFeatures;
/** Changed attributes values which are not commited */
QgsChangedAttributesMap mChangedAttributeValues;
/** deleted attributes fields which are not commited */
QgsAttributeIds mDeletedAttributeIds;
/** added attributes fields which are not commited */
QgsAttributeIds mAddedAttributeIds;
/** Changed geometries which are not commited. */
QgsGeometryMap mChangedGeometries;
/** field map to commit */
QgsFieldMap mUpdatedFields;
/** max field index */
int mMaxUpdatedIndex;
/** Geometry type as defined in enum WkbType (qgis.h) */
int mWkbType;
/** Renderer object which holds the information about how to display the features */
QgsRenderer *mRenderer;
/** Label */
QgsLabel *mLabel;
/** Display labels */
bool mLabelOn;
QStringList mCommitErrors;
QMap< QString, EditType > mEditTypes;
QMap< QString, QMap<QString, QVariant> > mValueMaps;
QMap< QString, RangeData > mRanges;
bool mFetching;
QgsRectangle mFetchRect;
QgsAttributeList mFetchAttributes;
QgsAttributeList mFetchNullAttributes;
bool mFetchGeometry;
QSet<int> mFetchConsidered;
QgsGeometryMap::iterator mFetchChangedGeomIt;
QgsFeatureList::iterator mFetchAddedFeaturesIt;
};
#endif