17#include <QApplication>
26 const QString &referencingLayerId,
const QString &referencingLayerName,
const QString &referencingLayerSource,
const QString &referencingLayerProviderKey,
27 const QString &referencedLayerId,
const QString &referencedLayerName,
const QString &referencedLayerSource,
const QString &referencedLayerProviderKey )
28 : mReferencingLayer( referencingLayerId, referencingLayerName, referencingLayerSource, referencingLayerProviderKey )
29 , mReferencedLayer( referencedLayerId, referencedLayerName, referencedLayerSource, referencedLayerProviderKey )
30 , mRelationId( relationId )
31 , mRelationName( relationName )
32 , mStrength( strength )
38 QList< QgsRelation > res;
40 switch ( mCardinality )
48 relation.
setId( mRelationId );
49 relation.
setName( mRelationName );
64 for (
int i = 0 ; i < std::min( mReferencingLayerFields.size(), mReferencedLayerFields.size() ); ++i )
66 relation.
addFieldPair( mReferencingLayerFields.at( i ), mReferencedLayerFields.at( i ) );
69 res.push_back( relation );
77 relationLeft.
setId( mRelationId + QStringLiteral(
"_forward" ) );
78 relationLeft.
setName( mRelationName + QStringLiteral(
"_forward" ) );
94 for (
int i = 0 ; i < std::min( mMappingReferencedLayerFields.size(), mReferencedLayerFields.size() ); ++i )
96 relationLeft.
addFieldPair( mMappingReferencedLayerFields.at( i ), mReferencedLayerFields.at( i ) );
99 res.push_back( relationLeft );
102 relationRight.
setId( mRelationId + QStringLiteral(
"_backward" ) );
103 relationRight.
setName( mRelationName + QStringLiteral(
"_backward" ) );
117 for (
int i = 0 ; i < std::min( mMappingReferencingLayerFields.size(), mReferencingLayerFields.size() ); ++i )
119 relationRight.
addFieldPair( mMappingReferencingLayerFields.at( i ), mReferencingLayerFields.at( i ) );
122 res.push_back( relationRight );
132 return mReferencingLayer;
137 return mReferencingLayer.
source;
147 mReferencingLayer.
source = sourceUri;
148 mReferencingLayer.
provider = provider;
155 return metadata->decodeUri( mReferencingLayer.
source ).value( QStringLiteral(
"layerName" ) ).toString();
162 return mReferencedLayer;
167 return mReferencedLayer.
source;
179 return metadata->decodeUri( mReferencedLayer.
source ).value( QStringLiteral(
"layerName" ) ).toString();
186 mReferencedLayer.
source = sourceUri;
187 mReferencedLayer.
provider = provider;
192 return mMappingTable;
197 mMappingTable = table;
202 return mMappingTable.
source;
214 return metadata->decodeUri( mMappingTable.
source ).value( QStringLiteral(
"layerName" ) ).toString();
221 mMappingTable.
source = sourceUri;
232 QDomElement relationElement = node.toElement();
234 if ( relationElement.tagName() != QLatin1String(
"relation" ) )
236 QgsLogger::warning( QApplication::translate(
"QgsRelation",
"Cannot create relation. Unexpected tag '%1'" ).arg( relationElement.tagName() ) );
239 QStringList referencingFields;
240 QStringList referencedFields;
241 const QDomNodeList fieldPairNodes { relationElement.elementsByTagName( QStringLiteral(
"fieldRef" ) ) };
242 for (
int j = 0; j < fieldPairNodes.length(); ++j )
244 const QDomElement fieldPairElement = fieldPairNodes.at( j ).toElement();
245 referencingFields.push_back( fieldPairElement.attribute( QStringLiteral(
"referencingField" ) ) );
246 referencedFields.push_back( fieldPairElement.attribute( QStringLiteral(
"referencedField" ) ) );
253 QgsWeakRelation rel{ relationElement.attribute( QStringLiteral(
"id" ) ),
254 relationElement.attribute( QStringLiteral(
"name" ) ),
262 relationElement.attribute( QStringLiteral(
"layerId" ) ),
263 relationElement.attribute( QStringLiteral(
"layerName" ) ),
264 relationElement.attribute( QStringLiteral(
"dataSource" ) ),
265 relationElement.attribute( QStringLiteral(
"providerKey" ) )
267 rel.setReferencedLayerFields( referencedFields );
268 rel.setReferencingLayerFields( referencingFields );
274 QgsWeakRelation rel{ relationElement.attribute( QStringLiteral(
"id" ) ),
275 relationElement.attribute( QStringLiteral(
"name" ) ),
278 relationElement.attribute( QStringLiteral(
"layerId" ) ),
279 relationElement.attribute( QStringLiteral(
"layerName" ) ),
280 relationElement.attribute( QStringLiteral(
"dataSource" ) ),
281 relationElement.attribute( QStringLiteral(
"providerKey" ) ),
288 rel.setReferencedLayerFields( referencedFields );
289 rel.setReferencingLayerFields( referencingFields );
309 QDomNodeList relationsNodeList = node.toElement().elementsByTagName( QStringLiteral(
"relation" ) );
310 QDomElement relationElement;
312 for (
int i = 0; i < relationsNodeList.size(); ++i )
314 relationElement = relationsNodeList.at( i ).toElement();
315 if ( relationElement.hasAttribute( QStringLiteral(
"id" ) ) && relationElement.attribute( QStringLiteral(
"id" ) ) == relation.
id() )
321 relationElement.setAttribute( QStringLiteral(
"layerId" ), relation.
referencedLayer()->
id() );
322 relationElement.setAttribute( QStringLiteral(
"layerName" ), relation.
referencedLayer()->
name() );
329 relationElement.setAttribute( QStringLiteral(
"layerId" ), relation.
referencingLayer()->
id() );
330 relationElement.setAttribute( QStringLiteral(
"layerName" ), relation.
referencingLayer()->
name() );
RelationshipStrength
Relationship strength.
@ ManyToMany
Many to many relationship.
@ ManyToOne
Many to one relationship.
@ OneToOne
One to one relationship.
@ OneToMany
One to many relationship.
static void warning(const QString &msg)
Goes to qWarning.
Base class for all map layer types.
QString providerType() const
Returns the provider type (provider key) for this layer.
QString id() const
Returns the layer's unique ID, which is used to access this layer from QgsProject.
QString publicSource(bool hidePassword=false) const
Gets a version of the internal layer definition that has sensitive bits removed (for example,...
Resolves relative paths into absolute paths and vice versa.
QString writePath(const QString &filename) const
Prepare a filename to save it to the project file.
Encapsulates a QGIS project, including sets of map layers and their styles, layouts,...
static QgsProject * instance()
Returns the QgsProject singleton instance.
QgsPathResolver pathResolver() const
Returns path resolver object with considering whether the project uses absolute or relative paths and...
static QgsProviderRegistry * instance(const QString &pluginPath=QString())
Means of accessing canonical single instance.
void setId(const QString &id)
Set an id for this relation.
void setReferencedLayer(const QString &id)
Set the referenced (parent) layer id.
QgsVectorLayer * referencedLayer
void setStrength(Qgis::RelationshipStrength strength)
Set a strength for this relation.
void addFieldPair(const QString &referencingField, const QString &referencedField)
Add a field pair which is part of this relation The first element of each pair are the field names of...
void setReferencingLayer(const QString &id)
Set the referencing (child) layer id.
QgsVectorLayer * referencingLayer
void setName(const QString &name)
Set a name for this relation.
void writeXml(QDomNode &node, QDomDocument &doc) const
Writes a relation to an XML structure.
Represents a vector layer which manages a vector based data sets.
The QgsWeakRelation class represent a QgsRelation with possibly unresolved layers or unmatched fields...
void setReferencedLayer(const QString &sourceUri, const QString &provider)
Sets the source for the referenced (or "parent" / "left") layer, by sourceUri and provider ID.
QgsVectorLayerRef referencedLayer() const
Returns a weak reference to the referenced (or "parent" / "left") layer.
QList< QgsRelation > resolvedRelations(const QgsProject *project, QgsVectorLayerRef::MatchType matchType=QgsVectorLayerRef::MatchType::All) const
Resolves a weak relation in the given project returning a list of possibly invalid QgsRelations and w...
void setMappingTable(const QgsVectorLayerRef &table)
Sets a weak reference to the mapping table, which forms the middle table in many-to-many relationship...
WeakRelationType
Enum to distinguish if the layer is referenced or referencing.
@ Referencing
The layer is referencing (or the "child" / "right" layer in the relationship)
@ Referenced
The layer is referenced (or the "parent" / "left" left in the relationship)
QString referencedLayerProvider() const
Returns the provider ID for the referenced (or "parent" / "left") layer.
QgsWeakRelation()
Default constructor for an invalid relation.
QString mappingTableProvider() const
Returns the provider ID for the mapping table, which forms the middle table in many-to-many relations...
QString mappingTableName() const
Returns the layer name of the mapping table, which forms the middle table in many-to-many relationshi...
QString mappingTableSource() const
Returns the source URI for the mapping table, which forms the middle table in many-to-many relationsh...
QString referencingLayerProvider() const
Returns the provider ID for the referencing (or "child" / "right") layer.
QgsVectorLayerRef referencingLayer() const
Returns a weak reference to the referencing (or "child" / "right") layer.
QString referencedLayerName() const
Returns the layer name of the referenced (or "parent" / "left") layer.
static void writeXml(const QgsVectorLayer *layer, WeakRelationType type, const QgsRelation &relation, QDomNode &node, QDomDocument &doc)
Writes a weak relation infoto an XML structure.
static QgsWeakRelation readXml(const QgsVectorLayer *layer, WeakRelationType type, const QDomNode &node, const QgsPathResolver resolver)
Returns a weak relation for the given layer.
void setReferencingLayer(const QString &sourceUri, const QString &provider)
Sets the source for the referencing (or "child" / "right") layer, by sourceUri and provider ID.
QString referencedLayerSource() const
Returns the source URI for the referenced (or "parent" / "left") layer.
QString referencingLayerSource() const
Returns the source URI for the referencing (or "child" / "right") layer.
QgsVectorLayerRef mappingTable() const
Returns a weak reference to the mapping table, which forms the middle table in many-to-many relations...
QString referencingLayerName() const
Returns the layer name of the referencing (or "child" / "right") layer.
Qgis::RelationshipStrength strength() const
Returns the strength of the relation.
TYPE * resolveWeakly(const QgsProject *project, MatchType matchType=MatchType::All)
Resolves the map layer by attempting to find a matching layer in a project using a weak match.
MatchType
Flag for match type in weak resolution.
QString source
Weak reference to layer public source.
QString provider
Weak reference to layer provider.