/************************************************************************
 * This file has been generated automatically from                      *
 *                                                                      *
 * src/core/qgspolymorphicrelation.h                                    *
 *                                                                      *
 * Do not edit manually ! Edit header and run scripts/sipify.py again   *
 ************************************************************************/






class QgsPolymorphicRelation
{
%Docstring(signature="appended")
A polymorphic relation consists of the same properties like a normal
relation except for the referenced layer which is calculated based on
one or several fields of the referencing layer.

In its most simple form, the referencing layer will just insert the
layer name of the referenced layer into this field. To be more precise,
a polymorphic relation is a set of normal relations having the same
referencing layer but having the referenced layer dynamically defined.
The polymorphic setting of the layer is solved by using an expression
which has to match some properties of the the referenced layer like the
table name, schema, uri, layer id, ...

.. versionadded:: 3.18
%End

%TypeHeaderCode
#include "qgspolymorphicrelation.h"
%End
  public:
    static const QMetaObject staticMetaObject;

  public:

    QgsPolymorphicRelation();
%Docstring
Default constructor. Creates an invalid relation.
%End
    ~QgsPolymorphicRelation();

    QgsPolymorphicRelation( const QgsRelationContext &context );
%Docstring
Constructor with context. Creates an invalid relation.
%End

    QgsPolymorphicRelation( const QgsPolymorphicRelation &other );
%Docstring
Copies a relation. This makes a shallow copy, relations are implicitly
shared and only duplicated when the copy is changed.
%End


    static QgsPolymorphicRelation createFromXml( const QDomNode &node, QgsReadWriteContext &context, const QgsRelationContext &relationContext = QgsRelationContext() );
%Docstring
Creates a relation from an XML structure. Used for reading .qgs
projects.

:param node: The dom node containing the relation information
:param context: to pass project translator
:param relationContext: a relation context

:return: A relation
%End

    void writeXml( QDomNode &node, QDomDocument &doc ) const;
%Docstring
Writes a relation to an XML structure. Used for saving .qgs projects

:param node: The parent node in which the relation will be created
:param doc: The document in which the relation will be saved
%End

    void setId( const QString &id );
%Docstring
Set an id for this relation
%End

    void setName( const QString &name );
%Docstring
Set a name for this relation
%End

    void setReferencingLayer( const QString &id );
%Docstring
Set the referencing (child) layer id. This layer will be searched in the
registry.
%End

    void addFieldPair( const QString &referencingField, const QString &referencedField );
%Docstring
Add a field pair which is part of this relation The first element of
each pair are the field names of the foreign key. The second element of
each pair are the field names of the matching primary key.

:param referencingField: The field name on the referencing (child) layer
                         (FK)
:param referencedField: The field name on the referenced (parent) layer
                        (PK)
%End


    QString name() const;
%Docstring
Returns a human readable name for this relation. Mostly used as title
for the children.

.. seealso:: :py:func:`id`

:return: A name
%End

    QString id() const;
%Docstring
A (project-wide) unique id for this relation

:return: The id
%End

    void generateId();
%Docstring
Generate a (project-wide) unique id for this relation
%End

    QString referencingLayerId() const;
%Docstring
Access the referencing (child) layer's id This is the layer which has
the field(s) which point to another layer

:return: The id of the referencing layer
%End

    QgsVectorLayer *referencingLayer() const;
%Docstring
Access the referencing (child) layer This is the layer which has the
field(s) which point to another layer

:return: The referencing layer
%End

    QMap< QString, QString > fieldPairs() const;
%Docstring
Returns the field pairs which form this relation The first element of
each pair are the field names of the foreign key. The second element of
each pair are the field names of the matching primary key.

:return: The fields forming the relation
%End
%MethodCode
    const QList< QgsRelation::FieldPair > &pairs = sipCpp->fieldPairs();
    sipRes = new QMap< QString, QString >();
    for ( const QgsRelation::FieldPair &pair : pairs )
    {
      sipRes->insert( pair.first, pair.second );
    }
%End

    QgsAttributeList referencedFields( const QString &layerId ) const;
%Docstring
Returns a list of attributes used to form the referenced fields (most
likely primary key) on the referenced (parent) layer.

:return: A list of attributes
%End

    QgsAttributeList referencingFields() const;
%Docstring
Returns a list of attributes used to form the referencing fields
(foreign key) on the referencing (child) layer.

:return: A list of attributes
%End

    bool isValid() const;
%Docstring
Returns the validity of this relation. Don't use the information if it's
not valid. A relation is considered valid if both referenced and
referencig layers are valid.

:return: ``True`` if the relation is valid
%End

    bool hasEqualDefinition( const QgsPolymorphicRelation &other ) const;
%Docstring
Compares the two :py:class:`QgsRelation`, ignoring the name and the ID.

:param other: The other relation

:return: ``True`` if they are similar
%End

    void updateRelationStatus();
%Docstring
Updates the validity status of this relation. Will be called internally
whenever a member is changed.
%End

    void setReferencedLayerField( const QString &referencedLayerField );
%Docstring
Sets the field in the referencing layer where the referenced layer
identifier is stored
%End

    QString referencedLayerField() const;
%Docstring
Returns the field in the referencing layer where the referenced layer
identifier is stored
%End

    void setReferencedLayerExpression( const QString &expression );
%Docstring
Sets the ``expression`` to identify the parent layer
%End

    QString referencedLayerExpression() const;
%Docstring
Returns the expression to identify the parent layer
%End

    void setReferencedLayerIds( const QStringList &childRelationIds );
%Docstring
Sets a list of layer ids to be used as potential referenced layers
%End

    QStringList referencedLayerIds() const;
%Docstring
Returns a list of layer ids to be used as potential referenced layers
%End

    QList<QgsRelation> generateRelations() const;
%Docstring
Returns a list of generated relations, based on the currently set
:py:func:`~QgsPolymorphicRelation.referencedLayerIds`
%End

    QString layerRepresentation( const QgsVectorLayer *layer ) const;
%Docstring
Returns layer representation as evaluated string
%End

    Qgis::RelationshipStrength strength() const;
%Docstring
Returns the relation strength for all the generated normal relations
%End

    void setRelationStrength( Qgis::RelationshipStrength relationStrength );
%Docstring
Sets the relation strength for all the generated normal relations
%End

};


/************************************************************************
 * This file has been generated automatically from                      *
 *                                                                      *
 * src/core/qgspolymorphicrelation.h                                    *
 *                                                                      *
 * Do not edit manually ! Edit header and run scripts/sipify.py again   *
 ************************************************************************/