QgsRelationManager Class Reference

This class manages a set of relations between layers. More...

#include <qgsrelationmanager.h>

Signals
void	relationsLoaded ()
	this signal is emitted when the relations were loaded after reading a project
void	changed ()
	Emitted when relations are added or removed to the manager.

Public Member Functions
	QgsRelationManager (QgsProject *project)
void	setRelations (const QList< QgsRelation > &relations)
	Will set the specified relations and remove any relation currently set.
const QMap< QString, QgsRelation > &	relations () const
	Get access to the relations managed by this class.
void	addRelation (const QgsRelation &relation)
	Add a relation.
void	removeRelation (const QString &id)
	Remove a relation.
void	removeRelation (const QgsRelation &relation)
	Remove a relation.
QgsRelation	relation (const QString &id) const
	Get access to a relation by its id.
void	clear ()
	Remove any relation managed by this class.
QList< QgsRelation >	referencingRelations (QgsVectorLayer *layer=0, int fieldIdx=-2) const
	Get all relations where the specified layer (and field) is the referencing part (i.e.
QList< QgsRelation >	referencedRelations (QgsVectorLayer *layer=0) const
	Get all relations where this layer is the referenced part (i.e.

Detailed Description

This class manages a set of relations between layers.

Constructor & Destructor Documentation

QgsRelationManager::QgsRelationManager ( QgsProject *  project )

explicit

Member Function Documentation

void QgsRelationManager::addRelation

(

const QgsRelation &

relation

)

Add a relation.

Parameters

relation

The relation to add.

void QgsRelationManager::changed ( )

signal

Emitted when relations are added or removed to the manager.

Note

added in QGIS 2.5

void QgsRelationManager::clear

(

)

Remove any relation managed by this class.

QList< QgsRelation > QgsRelationManager::referencedRelations

(

QgsVectorLayer *

layer = 0

)

const

Get all relations where this layer is the referenced part (i.e.

the parent table with the primary key being referenced from another layer).

Parameters

layer

The layer which should be searched for.

Returns

A list of relations where the specified layer is the referenced part.

QList< QgsRelation > QgsRelationManager::referencingRelations	(	QgsVectorLayer *	layer = 0,
		int	fieldIdx = -2
	)		const

Get all relations where the specified layer (and field) is the referencing part (i.e.

the child table with the foreign key).

Parameters

layer	The layer which should be searched for.
fieldIdx	The field which should be part of the foreign key. If not set will return all relations.

Returns

A list of relations matching the given layer and fieldIdx.

QgsRelation QgsRelationManager::relation

(

const QString &

id

)

const

Get access to a relation by its id.

Parameters

id	The id to search for

Returns

A relation. Invalid if not found.

const QMap< QString, QgsRelation > & QgsRelationManager::relations

(

)

const

Get access to the relations managed by this class.

Returns

A QMap where the key is the relation id, the value the relation object.

void QgsRelationManager::relationsLoaded ( )

signal

this signal is emitted when the relations were loaded after reading a project

void QgsRelationManager::removeRelation

(

const QString &

id

)

Remove a relation.

Parameters

id	The id of the relation to remove.

void QgsRelationManager::removeRelation

(

const QgsRelation &

relation

)

Remove a relation.

Parameters

relation

The relation to remove.

void QgsRelationManager::setRelations

(

const QList< QgsRelation > &

relations

)

Will set the specified relations and remove any relation currently set.

Parameters

relations

A list of relations to set.

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

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