QGIS API Documentation  3.20.0-Odense (decaadbb31)
qgsabstractrelationeditorwidget.cpp
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1 /***************************************************************************
2  qgsabstractrelationeditorwidget.cpp
3  ----------------------
4  begin : October 2020
5  copyright : (C) 2020 by Ivan Ivanov
6  email : [email protected]
7  ***************************************************************************/
8 
9 /***************************************************************************
10  * *
11  * This program is free software; you can redistribute it and/or modify *
12  * it under the terms of the GNU General Public License as published by *
13  * the Free Software Foundation; either version 2 of the License, or *
14  * (at your option) any later version. *
15  * *
16  ***************************************************************************/
17 
19 
20 #include "qgsfeatureiterator.h"
21 #include "qgsexpression.h"
22 #include "qgsfeature.h"
23 #include "qgsfeatureselectiondlg.h"
24 #include "qgsrelation.h"
25 #include "qgsrelationmanager.h"
26 #include "qgspolymorphicrelation.h"
27 #include "qgsvectorlayertools.h"
28 #include "qgsproject.h"
29 #include "qgstransactiongroup.h"
30 #include "qgsvectorlayerutils.h"
31 
32 #include <QMessageBox>
33 #include <QPushButton>
34 
35 QgsAbstractRelationEditorWidget::QgsAbstractRelationEditorWidget( const QVariantMap &config, QWidget *parent )
36  : QWidget( parent )
37 {
38  Q_UNUSED( config );
39 }
40 
42 {
44 
46  mFeature = feature;
47 
48  setObjectName( QStringLiteral( "referenced/" ) + mRelation.name() );
49 
51  updateUi();
52 }
53 
54 void QgsAbstractRelationEditorWidget::setRelations( const QgsRelation &relation, const QgsRelation &nmrelation )
55 {
56 
57  beforeSetRelations( relation, nmrelation );
58 
60  mNmRelation = nmrelation;
61 
62  if ( !mRelation.isValid() )
63  {
65  return;
66  }
67 
69 
70  const auto transactionGroups = QgsProject::instance()->transactionGroups();
71  for ( auto it = transactionGroups.constBegin(); it != transactionGroups.constEnd(); ++it )
72  {
73  if ( mNmRelation.isValid() )
74  {
75  if ( it.value()->layers().contains( mRelation.referencedLayer() ) &&
76  it.value()->layers().contains( mRelation.referencingLayer() ) &&
77  it.value()->layers().contains( mNmRelation.referencedLayer() ) )
79  }
80  else
81  {
82  if ( it.value()->layers().contains( mRelation.referencedLayer() ) &&
83  it.value()->layers().contains( mRelation.referencingLayer() ) )
85  }
86  }
87 
88  setObjectName( QStringLiteral( "referenced/" ) + mRelation.name() );
89 
91  updateUi();
92 }
93 
95 {
96  mEditorContext = context;
97 }
98 
100 {
101  return mEditorContext;
102 }
103 
104 void QgsAbstractRelationEditorWidget::setFeature( const QgsFeature &feature, bool update )
105 {
106  mFeature = feature;
107 
109 
110  if ( update )
111  updateUi();
112 }
113 
114 void QgsAbstractRelationEditorWidget::setNmRelationId( const QVariant &nmRelationId )
115 {
116  QgsRelation nmrelation = QgsProject::instance()->relationManager()->relation( nmRelationId.toString() );
117  beforeSetRelations( mRelation, nmrelation );
118  mNmRelation = nmrelation;
120  updateUi();
121 }
122 
124 {
125  return mNmRelation.id();
126 }
127 
129 {
130  return QString();
131 }
132 
133 void QgsAbstractRelationEditorWidget::setLabel( const QString &label )
134 {
135  Q_UNUSED( label )
136 }
137 
139 {
140  return false;
141 }
142 
144 {
145  Q_UNUSED( showLabel )
146 }
147 
149 {
151 }
152 
154 {
156 }
157 
159 {
160 }
161 
163 {
164  return mFeature;
165 }
166 
168 {
169  if ( state )
170  {
172  if ( mNmRelation.isValid() )
174  }
175  else
176  {
178  if ( mNmRelation.isValid() )
180  }
181 }
182 
184 {
186  if ( mNmRelation.isValid() )
188 }
189 
191 {
192  QgsAttributeMap keyAttrs;
193 
195 
196  // Fields of the linking table
197  const QgsFields fields = mRelation.referencingLayer()->fields();
198 
199  // For generated relations insert the referenced layer field
201  {
203  keyAttrs.insert( fields.indexFromName( polyRel.referencedLayerField() ), polyRel.layerRepresentation( mRelation.referencedLayer() ) );
204  }
205 
206  if ( mNmRelation.isValid() )
207  {
208  // only normal relations support m:n relation
209  Q_ASSERT( mNmRelation.type() == QgsRelation::Normal );
210 
211  // n:m Relation: first let the user create a new feature on the other table
212  // and autocreate a new linking feature.
213  QgsFeature f;
214  if ( !vlTools->addFeature( mNmRelation.referencedLayer(), QgsAttributeMap(), geometry, &f ) )
215  return;
216 
217  // Expression context for the linking table
219 
220  QgsAttributeMap linkAttributes = keyAttrs;
221  const auto constFieldPairs = mRelation.fieldPairs();
222  for ( const QgsRelation::FieldPair &fieldPair : constFieldPairs )
223  {
224  int index = fields.indexOf( fieldPair.first );
225  linkAttributes.insert( index, mFeature.attribute( fieldPair.second ) );
226  }
227 
228  const auto constNmFieldPairs = mNmRelation.fieldPairs();
229  for ( const QgsRelation::FieldPair &fieldPair : constNmFieldPairs )
230  {
231  int index = fields.indexOf( fieldPair.first );
232  linkAttributes.insert( index, f.attribute( fieldPair.second ) );
233  }
235 
237  }
238  else
239  {
240  const auto constFieldPairs = mRelation.fieldPairs();
241  for ( const QgsRelation::FieldPair &fieldPair : constFieldPairs )
242  {
243  keyAttrs.insert( fields.indexFromName( fieldPair.referencingField() ), mFeature.attribute( fieldPair.referencedField() ) );
244  }
245 
246  if ( !vlTools->addFeature( mRelation.referencingLayer(), keyAttrs, geometry ) )
247  return;
248  }
249 
250  updateUi();
251 }
252 
254 {
255  deleteFeatures( QgsFeatureIds() << fid );
256 }
257 
259 {
260  bool deleteFeatures = true;
261 
262  QgsVectorLayer *layer;
263  if ( mNmRelation.isValid() )
264  {
265  // only normal relations support m:n relation
266  Q_ASSERT( mNmRelation.type() == QgsRelation::Normal );
267 
268  layer = mNmRelation.referencedLayer();
269 
270  // When deleting a linked feature within an N:M relation,
271  // check if the feature is linked to more than just one feature.
272  // In case it is linked more than just once, ask the user for confirmation
273  // as it is likely he was not aware of the implications and might delete
274  // there may be several linking entries deleted along.
275 
276  QgsFeatureRequest deletedFeaturesRequest;
277  deletedFeaturesRequest.setFilterFids( fids );
278  deletedFeaturesRequest.setFlags( QgsFeatureRequest::NoGeometry );
279  deletedFeaturesRequest.setSubsetOfAttributes( QgsAttributeList() << mNmRelation.referencedFields().first() );
280 
281  QgsFeatureIterator deletedFeatures = layer->getFeatures( deletedFeaturesRequest );
282  QStringList deletedFeaturesPks;
284  while ( deletedFeatures.nextFeature( feature ) )
285  {
286  deletedFeaturesPks.append( QgsExpression::quotedValue( feature.attribute( mNmRelation.referencedFields().first() ) ) );
287  }
288 
289  QgsFeatureRequest linkingFeaturesRequest;
290  linkingFeaturesRequest.setFlags( QgsFeatureRequest::NoGeometry );
291  linkingFeaturesRequest.setNoAttributes();
292 
293  QString linkingFeaturesRequestExpression;
294  if ( !deletedFeaturesPks.empty() )
295  {
296  linkingFeaturesRequestExpression = QStringLiteral( "%1 IN (%2)" ).arg( QgsExpression::quotedColumnRef( mNmRelation.fieldPairs().first().first ), deletedFeaturesPks.join( ',' ) );
297  linkingFeaturesRequest.setFilterExpression( linkingFeaturesRequestExpression );
298 
299  QgsFeatureIterator relatedLinkingFeatures = mNmRelation.referencingLayer()->getFeatures( linkingFeaturesRequest );
300 
301  int relatedLinkingFeaturesCount = 0;
302  while ( relatedLinkingFeatures.nextFeature( feature ) )
303  {
304  relatedLinkingFeaturesCount++;
305  }
306 
307  if ( deletedFeaturesPks.size() == 1 && relatedLinkingFeaturesCount > 1 )
308  {
309  QMessageBox messageBox( QMessageBox::Question, tr( "Really delete entry?" ), tr( "The entry on %1 is still linked to %2 features on %3. Do you want to delete it?" ).arg( mNmRelation.referencedLayer()->name(), QString::number( relatedLinkingFeaturesCount ), mRelation.referencedLayer()->name() ), QMessageBox::NoButton, this );
310  messageBox.addButton( QMessageBox::Cancel );
311  QAbstractButton *deleteButton = messageBox.addButton( tr( "Delete" ), QMessageBox::AcceptRole );
312 
313  messageBox.exec();
314  if ( messageBox.clickedButton() != deleteButton )
315  deleteFeatures = false;
316  }
317  else if ( deletedFeaturesPks.size() > 1 && relatedLinkingFeaturesCount > deletedFeaturesPks.size() )
318  {
319  QMessageBox messageBox( QMessageBox::Question, tr( "Really delete entries?" ), tr( "The %1 entries on %2 are still linked to %3 features on %4. Do you want to delete them?" ).arg( QString::number( deletedFeaturesPks.size() ), mNmRelation.referencedLayer()->name(), QString::number( relatedLinkingFeaturesCount ), mRelation.referencedLayer()->name() ), QMessageBox::NoButton, this );
320  messageBox.addButton( QMessageBox::Cancel );
321  QAbstractButton *deleteButton = messageBox.addButton( tr( "Delete" ), QMessageBox::AcceptRole );
322 
323  messageBox.exec();
324  if ( messageBox.clickedButton() != deleteButton )
325  deleteFeatures = false;
326  }
327  }
328  }
329  else
330  {
331  layer = mRelation.referencingLayer();
332  }
333 
335  if ( QgsVectorLayerUtils::impactsCascadeFeatures( layer, fids, QgsProject::instance(), infoContext ) )
336  {
337  QString childrenInfo;
338  int childrenCount = 0;
339  const auto infoContextLayers = infoContext.layers();
340  for ( QgsVectorLayer *chl : infoContextLayers )
341  {
342  childrenCount += infoContext.duplicatedFeatures( chl ).size();
343  childrenInfo += ( tr( "%1 feature(s) on layer \"%2\", " ).arg( infoContext.duplicatedFeatures( chl ).size() ).arg( chl->name() ) );
344  }
345 
346  // for extra safety to make sure we know that the delete can have impact on children and joins
347  int res = QMessageBox::question( this, tr( "Delete at least %1 feature(s) on other layer(s)" ).arg( childrenCount ),
348  tr( "Delete %1 feature(s) on layer \"%2\", %3 as well\nand all of its other descendants.\nDelete these features?" ).arg( fids.count() ).arg( layer->name() ).arg( childrenInfo ),
349  QMessageBox::Yes | QMessageBox::No );
350  if ( res != QMessageBox::Yes )
351  deleteFeatures = false;
352  }
353 
354  if ( deleteFeatures )
355  {
357  layer->deleteFeatures( fids, &context );
358  const auto contextLayers = context.handledLayers();
359  if ( contextLayers.size() > 1 )
360  {
361  int deletedCount = 0;
362  QString feedbackMessage;
363  for ( QgsVectorLayer *contextLayer : contextLayers )
364  {
365  feedbackMessage += tr( "%1 on layer %2. " ).arg( context.handledFeatures( contextLayer ).size() ).arg( contextLayer->name() );
366  deletedCount += context.handledFeatures( contextLayer ).size();
367  }
368  mEditorContext.mainMessageBar()->pushMessage( tr( "%1 features deleted: %2" ).arg( deletedCount ).arg( feedbackMessage ), Qgis::MessageLevel::Success );
369  }
370 
371  updateUi();
372  }
373 }
374 
376 {
377  QgsVectorLayer *layer = nullptr;
378 
379  if ( mNmRelation.isValid() )
380  {
381  // only normal relations support m:n relation
382  Q_ASSERT( mNmRelation.type() == QgsRelation::Normal );
383 
384  layer = mNmRelation.referencedLayer();
385  }
386  else
387  layer = mRelation.referencingLayer();
388 
389  QgsFeatureSelectionDlg *selectionDlg = new QgsFeatureSelectionDlg( layer, mEditorContext, this );
390  selectionDlg->setAttribute( Qt::WA_DeleteOnClose );
391 
393  selectionDlg->setWindowTitle( tr( "Link existing child features for parent %1 \"%2\"" ).arg( mRelation.referencedLayer()->name(), displayString ) );
394 
395  connect( selectionDlg, &QDialog::accepted, this, &QgsAbstractRelationEditorWidget::onLinkFeatureDlgAccepted );
396  selectionDlg->show();
397 }
398 
400 {
401  QgsFeatureSelectionDlg *selectionDlg = qobject_cast<QgsFeatureSelectionDlg *>( sender() );
402  if ( mNmRelation.isValid() )
403  {
404  // only normal relations support m:n relation
405  Q_ASSERT( mNmRelation.type() == QgsRelation::Normal );
406 
409  .setFilterFids( selectionDlg->selectedFeatures() )
411 
412  QgsFeature relatedFeature;
413 
414  QgsFeatureList newFeatures;
415 
416  // Fields of the linking table
417  const QgsFields fields = mRelation.referencingLayer()->fields();
418 
419  // Expression context for the linking table
421 
422  QgsAttributeMap linkAttributes;
423 
425  {
427  Q_ASSERT( polyRel.isValid() );
428 
429  linkAttributes.insert( fields.indexFromName( polyRel.referencedLayerField() ),
431  }
432 
433  const auto constFieldPairs = mRelation.fieldPairs();
434  for ( const QgsRelation::FieldPair &fieldPair : constFieldPairs )
435  {
436  int index = fields.indexOf( fieldPair.first );
437  linkAttributes.insert( index, mFeature.attribute( fieldPair.second ) );
438  }
439 
440  while ( it.nextFeature( relatedFeature ) )
441  {
442  const auto constFieldPairs = mNmRelation.fieldPairs();
443  for ( const QgsRelation::FieldPair &fieldPair : constFieldPairs )
444  {
445  int index = fields.indexOf( fieldPair.first );
446  linkAttributes.insert( index, relatedFeature.attribute( fieldPair.second ) );
447  }
449 
450  newFeatures << linkFeature;
451  }
452 
453  mRelation.referencingLayer()->addFeatures( newFeatures );
454  QgsFeatureIds ids;
455  const auto constNewFeatures = newFeatures;
456  for ( const QgsFeature &f : constNewFeatures )
457  ids << f.id();
459  }
460  else
461  {
462  QMap<int, QVariant> keys;
463  const auto constFieldPairs = mRelation.fieldPairs();
464  for ( const QgsRelation::FieldPair &fieldPair : constFieldPairs )
465  {
466  int idx = mRelation.referencingLayer()->fields().lookupField( fieldPair.referencingField() );
467  QVariant val = mFeature.attribute( fieldPair.referencedField() );
468  keys.insert( idx, val );
469  }
470 
471  const auto constSelectedFeatures = selectionDlg->selectedFeatures();
472  for ( QgsFeatureId fid : constSelectedFeatures )
473  {
474  QgsVectorLayer *referencingLayer = mRelation.referencingLayer();
476  {
478 
479  Q_ASSERT( polyRel.isValid() );
480 
482  referencingLayer->fields().indexFromName( polyRel.referencedLayerField() ),
484  }
485 
486  QMapIterator<int, QVariant> it( keys );
487  while ( it.hasNext() )
488  {
489  it.next();
490  referencingLayer->changeAttributeValue( fid, it.key(), it.value() );
491  }
492  }
493  }
494 
495  updateUi();
496 }
497 
499 {
500  unlinkFeatures( QgsFeatureIds() << fid );
501 }
502 
504 {
505  if ( mNmRelation.isValid() )
506  {
507  // only normal relations support m:n relation
508  Q_ASSERT( mNmRelation.type() == QgsRelation::Normal );
509 
512  .setFilterFids( fids )
513  .setSubsetOfAttributes( mNmRelation.referencedFields() ) );
514 
515  QgsFeature f;
516 
517  QStringList filters;
518 
519  while ( selectedIterator.nextFeature( f ) )
520  {
521  filters << '(' + mNmRelation.getRelatedFeaturesRequest( f ).filterExpression()->expression() + ')';
522  }
523 
524  QString filter = QStringLiteral( "(%1) AND (%2)" ).arg(
526  filters.join( QLatin1String( " OR " ) ) );
527 
529  .setNoAttributes()
530  .setFilterExpression( filter ) );
531 
532  QgsFeatureIds fids;
533 
534  while ( linkedIterator.nextFeature( f ) )
535  {
536  fids << f.id();
537  QgsDebugMsgLevel( FID_TO_STRING( f.id() ), 4 );
538  }
539 
541  }
542  else
543  {
544  QMap<int, QgsField> keyFields;
545  const auto constFieldPairs = mRelation.fieldPairs();
546  for ( const QgsRelation::FieldPair &fieldPair : constFieldPairs )
547  {
548  int idx = mRelation.referencingLayer()->fields().lookupField( fieldPair.referencingField() );
549  if ( idx < 0 )
550  {
551  QgsDebugMsg( QStringLiteral( "referencing field %1 not found" ).arg( fieldPair.referencingField() ) );
552  return;
553  }
554  QgsField fld = mRelation.referencingLayer()->fields().at( idx );
555  keyFields.insert( idx, fld );
556  }
557 
558  const auto constFeatureids = fids;
559  for ( QgsFeatureId fid : constFeatureids )
560  {
561  QgsVectorLayer *referencingLayer = mRelation.referencingLayer();
563  {
565 
566  Q_ASSERT( mRelation.polymorphicRelation().isValid() );
567 
569  referencingLayer->fields().indexFromName( polyRel.referencedLayerField() ),
570  referencingLayer->fields().field( polyRel.referencedLayerField() ).type() );
571  }
572 
573  QMapIterator<int, QgsField> it( keyFields );
574  while ( it.hasNext() )
575  {
576  it.next();
577  mRelation.referencingLayer()->changeAttributeValue( fid, it.key(), QVariant( it.value().type() ) );
578  }
579  }
580  }
581 
582  updateUi();
583 }
584 
586 {}
587 
588 void QgsAbstractRelationEditorWidget::setTitle( const QString &title )
589 {
590  Q_UNUSED( title )
591 }
592 
594 {
595  Q_UNUSED( newRelation )
596  Q_UNUSED( newFeature )
597 }
598 
600 {}
601 
602 void QgsAbstractRelationEditorWidget::beforeSetRelations( const QgsRelation &newRelation, const QgsRelation &newNmRelation )
603 {
604  Q_UNUSED( newRelation )
605  Q_UNUSED( newNmRelation )
606 }
607 
609 {}
610 
612 {
613  duplicateFeatures( QgsFeatureIds() << fid );
614 }
615 
617 {
619 
620  QgsFeatureIterator fit = layer->getFeatures( QgsFeatureRequest().setFilterFids( fids ) );
621  QgsFeature f;
622  while ( fit.nextFeature( f ) )
623  {
624  QgsVectorLayerUtils::QgsDuplicateFeatureContext duplicatedFeatureContext;
625  QgsVectorLayerUtils::duplicateFeature( layer, f, QgsProject::instance(), duplicatedFeatureContext );
626  }
627 }
628 
630 {
631  updateUi();
632 }
633 
634 
636 
637 
639  : QWidget( parent )
640  , mRelation( relation )
641 {
642 }
643 
645 {
646  return mLayer;
647 }
648 
650 {
651  return mRelation;
652 }
653 
655 {
656  mNmRelation = nmRelation;
657 }
658 
660 {
661  return mNmRelation;
662 }
663 
664 
666 
667 
669 {
670 }
virtual void setNmRelation(const QgsRelation &nmRelation)
Set the nm relation for this widget.
QgsRelation relation() const
Returns the relation for which this configuration widget applies.
virtual QgsRelation nmRelation() const
Returns the nm relation for which this configuration widget applies.
QgsAbstractRelationEditorConfigWidget(const QgsRelation &relation, QWidget *parent)
Create a new configuration widget.
QgsVectorLayer * layer()
Returns the layer for which this configuration widget applies.
QgsAbstractRelationEditorWidgetFactory()
Creates a new relation widget factory with given name.
void toggleEditing(bool state)
Toggles editing state of the widget.
void deleteFeatures(const QgsFeatureIds &fids)
Deletes the features with fids.
void onLinkFeatureDlgAccepted()
Called when the link feature dialog is confirmed by the user.
bool forceSuppressFormPopup() const
Determines the force suppress form popup status that is configured for this widget.
virtual void afterSetRelations()
A hook called right after setRelations() is executed, but before updateUi() is called.
void setRelationFeature(const QgsRelation &relation, const QgsFeature &feature)
Sets the relation and the feature.
virtual void setEditorContext(const QgsAttributeEditorContext &context)
Sets the editor context.
virtual Q_DECL_DEPRECATED void setTitle(const QString &title)
Sets the title of the widget, if it is wrapped within a QgsCollapsibleGroupBox.
Q_DECL_DEPRECATED QString label() const
Determines the label of this element.
void showEvent(QShowEvent *)
Refresh the UI when the widget becomes visible.
void setLabel(const QString &label=QString())
Sets label for this element If it's empty it takes the relation id as label.
void linkFeature()
Links a new feature to the relation.
Q_DECL_DEPRECATED void updateTitle()
Updates the title contents to reflect the current state of the widget.
QgsAbstractRelationEditorWidget(const QVariantMap &config, QWidget *parent=nullptr)
Constructor.
void setRelations(const QgsRelation &relation, const QgsRelation &nmrelation)
Sets the relation(s) for this widget If only one relation is set, it will act as a simple 1:N relatio...
void addFeature(const QgsGeometry &geometry=QgsGeometry())
Adds a new feature with given geometry.
virtual void beforeSetRelations(const QgsRelation &newRelation, const QgsRelation &newNmRelation)
A hook called right before setRelations() is executed.
QgsAttributeEditorContext editorContext() const
Returns the attribute editor context.
Q_DECL_DEPRECATED bool showLabel() const
Defines if a title label should be shown for this widget.
virtual void updateUi()
A hook called every time the state of the relation editor widget has changed via calling its set* met...
QgsRelation relation() const
Returns the relation.
virtual QVariantMap config() const =0
Returns the widget configuration.
virtual void beforeSetRelationFeature(const QgsRelation &newRelation, const QgsFeature &newFeature)
A hook called right before setRelationFeature() is executed.
void setFeature(const QgsFeature &feature, bool update=true)
Sets the feature being edited and updates the UI unless update is set to false.
void unlinkFeatures(const QgsFeatureIds &fids)
Unlinks the features with fids.
void deleteFeature(QgsFeatureId fid=QgsFeatureId())
Delete a feature with given fid.
QgsFeature feature() const
Returns the widget's current feature.
QVariant nmRelationId() const
Determines the relation id of the second relation involved in an N:M relation.
virtual void afterSetRelationFeature()
A hook called right after setRelationFeature() is executed, but before updateUi() is called.
Q_DECL_DEPRECATED void setShowLabel(bool showLabel)
Defines if a title label should be shown for this widget.
void saveEdits()
Saves the current modifications in the relation.
void unlinkFeature(QgsFeatureId fid=QgsFeatureId())
Unlinks a feature with given fid.
void duplicateFeature(const QgsFeatureId &fid)
Duplicates a feature.
void duplicateFeatures(const QgsFeatureIds &fids)
Duplicates features.
void setForceSuppressFormPopup(bool forceSuppressFormPopup)
Sets force suppress form popup status with forceSuppressFormPopup configured for this widget.
void setNmRelationId(const QVariant &nmRelationId=QVariant())
Sets nmRelationId for the relation id of the second relation involved in an N:M relation.
This class contains context information for attribute editor widgets.
void setFormFeature(const QgsFeature &feature)
Set current feature for the currently edited form or table row.
QgsMessageBar * mainMessageBar()
Returns the main message bar.
const QgsVectorLayerTools * vectorLayerTools() const
Returns the associated vector layer tools.
Expression contexts are used to encapsulate the parameters around which a QgsExpression should be eva...
QString expression() const
Returns the original, unmodified expression string.
static QString quotedValue(const QVariant &value)
Returns a string representation of a literal value, including appropriate quotations where required.
static QString quotedColumnRef(QString name)
Returns a quoted column reference (in double quotes)
Wrapper for iterator of features from vector data provider or vector layer.
bool nextFeature(QgsFeature &f)
This class wraps a request for features to a vector layer (or directly its vector data provider).
QgsExpression * filterExpression() const
Returns the filter expression if set.
QgsFeatureRequest & setFilterFids(const QgsFeatureIds &fids)
Sets feature IDs that should be fetched.
QgsFeatureRequest & setFlags(QgsFeatureRequest::Flags flags)
Sets flags that affect how features will be fetched.
QgsFeatureRequest & setSubsetOfAttributes(const QgsAttributeList &attrs)
Set a subset of attributes that will be fetched.
QgsFeatureRequest & setFilterExpression(const QString &expression)
Set the filter expression.
@ NoGeometry
Geometry is not required. It may still be returned if e.g. required for a filter condition.
QgsFeatureRequest & setNoAttributes()
Set that no attributes will be fetched.
const QgsFeatureIds & selectedFeatures()
Gets the selected features.
The feature class encapsulates a single feature including its unique ID, geometry and a list of field...
Definition: qgsfeature.h:56
QVariant attribute(const QString &name) const
Lookup attribute value by attribute name.
Definition: qgsfeature.cpp:302
Q_GADGET QgsFeatureId id
Definition: qgsfeature.h:64
Encapsulate a field in an attribute table or data source.
Definition: qgsfield.h:51
QVariant::Type type
Definition: qgsfield.h:58
Container of fields for a vector layer.
Definition: qgsfields.h:45
int indexFromName(const QString &fieldName) const
Gets the field index from the field name.
Definition: qgsfields.cpp:202
int indexOf(const QString &fieldName) const
Gets the field index from the field name.
Definition: qgsfields.cpp:207
QgsField field(int fieldIdx) const
Returns the field at particular index (must be in range 0..N-1).
Definition: qgsfields.cpp:168
QgsField at(int i) const
Returns the field at particular index (must be in range 0..N-1).
Definition: qgsfields.cpp:163
int lookupField(const QString &fieldName) const
Looks up field's index from the field name.
Definition: qgsfields.cpp:344
A geometry is the spatial representation of a feature.
Definition: qgsgeometry.h:124
QString name
Definition: qgsmaplayer.h:73
void pushMessage(const QString &text, Qgis::MessageLevel level=Qgis::MessageLevel::Info, int duration=-1)
A convenience method for pushing a message with the specified text to the bar.
A polymorphic relation consists of the same properties like a normal relation except for the referenc...
QString layerRepresentation(const QgsVectorLayer *layer) const
Returns layer representation as evaluated string.
QgsRelationManager * relationManager
Definition: qgsproject.h:109
static QgsProject * instance()
Returns the QgsProject singleton instance.
Definition: qgsproject.cpp:467
QMap< QPair< QString, QString >, QgsTransactionGroup * > transactionGroups()
Map of transaction groups.
Q_INVOKABLE QgsRelation relation(const QString &id) const
Gets access to a relation by its id.
Defines a relation between matching fields of the two involved tables of a relation.
Definition: qgsrelation.h:89
QString name
Definition: qgsrelation.h:49
QgsVectorLayer * referencedLayer
Definition: qgsrelation.h:48
@ Generated
A generated relation is a child of a polymorphic relation.
Definition: qgsrelation.h:62
@ Normal
A normal relation.
Definition: qgsrelation.h:61
QList< QgsRelation::FieldPair > fieldPairs() const
Returns the field pairs which form this relation The first element of each pair are the field names o...
Q_GADGET QString id
Definition: qgsrelation.h:46
RelationType type() const
Returns the type of the relation.
QgsPolymorphicRelation polymorphicRelation
Definition: qgsrelation.h:52
QgsAttributeList referencedFields() const
Returns a list of attributes used to form the referenced fields (most likely primary key) on the refe...
QgsVectorLayer * referencingLayer
Definition: qgsrelation.h:47
bool isValid
Definition: qgsrelation.h:50
QgsFeatureRequest getRelatedFeaturesRequest(const QgsFeature &feature) const
Creates a request to return all the features on the referencing (child) layer which have a foreign ke...
Methods in this class are used to handle basic operations on vector layers.
virtual bool startEditing(QgsVectorLayer *layer) const =0
This will be called, whenever a vector layer should be switched to edit mode.
virtual bool saveEdits(QgsVectorLayer *layer) const =0
Should be called, when the features should be committed but the editing session is not ended.
virtual bool addFeature(QgsVectorLayer *layer, const QgsAttributeMap &defaultValues=QgsAttributeMap(), const QgsGeometry &defaultGeometry=QgsGeometry(), QgsFeature *feature=nullptr) const =0
This method should/will be called, whenever a new feature will be added to the layer.
virtual bool stopEditing(QgsVectorLayer *layer, bool allowCancel=true) const =0
Will be called, when an editing session is ended and the features should be committed.
Contains mainly the QMap with QgsVectorLayer and QgsFeatureIds do list all the duplicated features.
QgsFeatureIds duplicatedFeatures(QgsVectorLayer *layer) const
Returns the duplicated features in the given layer.
QList< QgsVectorLayer * > layers() const
Returns all the layers on which features have been duplicated.
static QgsFeature duplicateFeature(QgsVectorLayer *layer, const QgsFeature &feature, QgsProject *project, QgsDuplicateFeatureContext &duplicateFeatureContext, const int maxDepth=0, int depth=0, QList< QgsVectorLayer * > referencedLayersBranch=QList< QgsVectorLayer * >())
Duplicates a feature and it's children (one level deep).
static QString getFeatureDisplayString(const QgsVectorLayer *layer, const QgsFeature &feature)
static QgsFeature createFeature(const QgsVectorLayer *layer, const QgsGeometry &geometry=QgsGeometry(), const QgsAttributeMap &attributes=QgsAttributeMap(), QgsExpressionContext *context=nullptr)
Creates a new feature ready for insertion into a layer.
static bool impactsCascadeFeatures(const QgsVectorLayer *layer, const QgsFeatureIds &fids, const QgsProject *project, QgsDuplicateFeatureContext &context, QgsVectorLayerUtils::CascadedFeatureFlags flags=QgsVectorLayerUtils::CascadedFeatureFlags())
Represents a vector layer which manages a vector based data sets.
QgsFeatureIterator getFeatures(const QgsFeatureRequest &request=QgsFeatureRequest()) const FINAL
Queries the layer for features specified in request.
QgsFields fields() const FINAL
Returns the list of fields of this layer.
bool addFeatures(QgsFeatureList &features, QgsFeatureSink::Flags flags=QgsFeatureSink::Flags()) FINAL
Adds a list of features to the sink.
bool deleteFeatures(const QgsFeatureIds &fids, DeleteContext *context=nullptr)
Deletes a set of features from the layer (but does not commit it)
QgsExpressionContext createExpressionContext() const FINAL
This method needs to be reimplemented in all classes which implement this interface and return an exp...
bool changeAttributeValue(QgsFeatureId fid, int field, const QVariant &newValue, const QVariant &oldValue=QVariant(), bool skipDefaultValues=false)
Changes an attribute value for a feature (but does not immediately commit the changes).
bool addFeature(QgsFeature &feature, QgsFeatureSink::Flags flags=QgsFeatureSink::Flags()) FINAL
Adds a single feature to the sink.
Q_INVOKABLE void selectByIds(const QgsFeatureIds &ids, QgsVectorLayer::SelectBehavior behavior=QgsVectorLayer::SetSelection)
Selects matching features using a list of feature IDs.
QMap< int, QVariant > QgsAttributeMap
Definition: qgsattributes.h:38
QList< QgsFeature > QgsFeatureList
Definition: qgsfeature.h:736
QSet< QgsFeatureId > QgsFeatureIds
Definition: qgsfeatureid.h:37
#define FID_TO_STRING(fid)
Definition: qgsfeatureid.h:33
qint64 QgsFeatureId
64 bit feature ids negative numbers are used for uncommitted/newly added features
Definition: qgsfeatureid.h:28
QList< int > QgsAttributeList
Definition: qgsfield.h:26
#define QgsDebugMsgLevel(str, level)
Definition: qgslogger.h:39
#define QgsDebugMsg(str)
Definition: qgslogger.h:38
Context for cascade delete features.
QList< QgsVectorLayer * > handledLayers(bool includeAuxiliaryLayers=true) const
Returns a list of all layers affected by the delete operation.
QgsFeatureIds handledFeatures(QgsVectorLayer *layer) const
Returns a list of feature IDs from the specified layer affected by the delete operation.