QgsVectorLayerJoinBuffer Class Reference

Manages joined fields for a vector layer. More...

#include <qgsvectorlayerjoinbuffer.h>

Signals
void	joinedFieldsChanged ()
	Emitted whenever the list of joined fields changes (e.g.

Public Member Functions
	QgsVectorLayerJoinBuffer (QgsVectorLayer *layer=0)
	~QgsVectorLayerJoinBuffer ()
bool	addJoin (const QgsVectorJoinInfo &joinInfo)
	Joins another vector layer to this layer.
void	removeJoin (const QString &joinLayerId)
	Removes a vector layer join.
void	updateFields (QgsFields &fields)
	Updates field map with joined attributes.
void	createJoinCaches ()
	Calls cacheJoinLayer() for all vector joins.
void	writeXml (QDomNode &layer_node, QDomDocument &document) const
	Saves mVectorJoins to xml under the layer node.
void	readXml (const QDomNode &layer_node)
	Reads joins from project file.
bool	containsJoins () const
	Quick way to test if there is any join at all.
const QgsVectorJoinList &	vectorJoins () const
const QgsVectorJoinInfo *	joinForFieldIndex (int index, const QgsFields &fields, int &sourceFieldIndex) const
	Finds the vector join for a layer field index.
int	joinedFieldsOffset (const QgsVectorJoinInfo *info, const QgsFields &fields)
	Find out what is the first index of the join within fields.
QgsVectorLayerJoinBuffer *	clone () const
	Create a copy of the join buffer.

Static Public Member Functions
static QVector< int >	joinSubsetIndices (QgsVectorLayer *joinLayer, const QStringList &joinFieldsSubset)
	Return a vector of indices for use in join based on field names from the layer.

Detailed Description

Manages joined fields for a vector layer.

Constructor & Destructor Documentation

QgsVectorLayerJoinBuffer::QgsVectorLayerJoinBuffer

(

QgsVectorLayer *

layer = 0

)

QgsVectorLayerJoinBuffer::~QgsVectorLayerJoinBuffer

(

)

Member Function Documentation

bool QgsVectorLayerJoinBuffer::addJoin

(

const QgsVectorJoinInfo &

joinInfo

)

Joins another vector layer to this layer.

Parameters

joinInfo

join object containing join layer id, target and source field

Returns

(since 2.6) whether the join was successfully added

QgsVectorLayerJoinBuffer * QgsVectorLayerJoinBuffer::clone

(

)

const

Create a copy of the join buffer.

Note

added in 2.6

bool QgsVectorLayerJoinBuffer::containsJoins ( ) const

inline

Quick way to test if there is any join at all.

void QgsVectorLayerJoinBuffer::createJoinCaches

(

)

Calls cacheJoinLayer() for all vector joins.

void QgsVectorLayerJoinBuffer::joinedFieldsChanged ( )

signal

Emitted whenever the list of joined fields changes (e.g.

added join or joined layer's fields change)

Note

added in 2.6

int QgsVectorLayerJoinBuffer::joinedFieldsOffset	(	const QgsVectorJoinInfo *	info,
		const QgsFields &	fields
	)

Find out what is the first index of the join within fields.

Returns -1 if join is not present

Note

added in 2.6

const QgsVectorJoinInfo * QgsVectorLayerJoinBuffer::joinForFieldIndex	(	int	index,
		const QgsFields &	fields,
		int &	sourceFieldIndex
	)		const

Finds the vector join for a layer field index.

Parameters

index	this layers attribute index
fields	fields of the vector layer (including joined fields)
sourceFieldIndex	Output: field's index in source layer

QVector< int > QgsVectorLayerJoinBuffer::joinSubsetIndices ( QgsVectorLayer *  joinLayer, const QStringList &  joinFieldsSubset  )

static

Return a vector of indices for use in join based on field names from the layer.

Note

added in 2.6

void QgsVectorLayerJoinBuffer::readXml

(

const QDomNode &

layer_node

)

Reads joins from project file.

void QgsVectorLayerJoinBuffer::removeJoin

(

const QString &

joinLayerId

)

Removes a vector layer join.

void QgsVectorLayerJoinBuffer::updateFields

(

QgsFields &

fields

)

Updates field map with joined attributes.

Parameters

fields

map to append joined attributes

const QgsVectorJoinList& QgsVectorLayerJoinBuffer::vectorJoins ( ) const

inline

void QgsVectorLayerJoinBuffer::writeXml	(	QDomNode &	layer_node,
		QDomDocument &	document
	)		const

Saves mVectorJoins to xml under the layer node.

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

• /tmp/buildd/qgis-2.6.0+wheezy1/src/core/qgsvectorlayerjoinbuffer.h
• /tmp/buildd/qgis-2.6.0+wheezy1/src/core/qgsvectorlayerjoinbuffer.cpp