QGIS API Documentation  3.17.0-Master (ca637cfeb2)
qgsalgorithmaddincrementalfield.h
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1 /***************************************************************************
2  qgsalgorithmaddincrementalfield.h
3  ---------------------------------
4  begin : April 2017
5  copyright : (C) 2017 by Nyall Dawson
6  email : nyall dot dawson at gmail dot com
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 
18 #ifndef QGSALGORITHMADDINCREMENTALFIELD_H
19 #define QGSALGORITHMADDINCREMENTALFIELD_H
20 
21 #define SIP_NO_FILE
22 
23 #include "qgis_sip.h"
24 #include "qgsprocessingalgorithm.h"
25 
27 
31 class QgsAddIncrementalFieldAlgorithm : public QgsProcessingFeatureBasedAlgorithm
32 {
33 
34  public:
35 
36  QgsAddIncrementalFieldAlgorithm() = default;
37  QString name() const override;
38  QString displayName() const override;
39  QStringList tags() const override;
40  QString group() const override;
41  QString groupId() const override;
42  QString shortHelpString() const override;
43  QList<int> inputLayerTypes() const override;
44  QgsAddIncrementalFieldAlgorithm *createInstance() const override SIP_FACTORY;
45 
46  protected:
47 
48  void initParameters( const QVariantMap &configuration = QVariantMap() ) override;
49  QString outputName() const override;
50  QgsFields outputFields( const QgsFields &inputFields ) const override;
52 
53  bool prepareAlgorithm( const QVariantMap &parameters, QgsProcessingContext &context, QgsProcessingFeedback *feedback ) override;
54  QgsFeatureRequest request() const override;
55  QgsFeatureList processFeature( const QgsFeature &feature, QgsProcessingContext &context, QgsProcessingFeedback *feedback ) override;
56  bool supportInPlaceEdit( const QgsMapLayer *layer ) const override;
57 
58  private:
59 
60  long long mStartValue = 0;
61  long long mValue = 0;
62  QString mFieldName;
63  QHash< QgsAttributes, long long > mGroupedValues;
64  mutable QgsFields mFields;
65  QStringList mGroupedFieldNames;
66  QgsAttributeList mGroupedFields;
67 
68  QString mSortExpressionString;
69  bool mSortAscending = true;
70  bool mSortNullsFirst = false;
71 
72 };
73 
75 
76 #endif // QGSNATIVEALGORITHMS_H
77 
78 
virtual QString outputName() const =0
Returns the translated, user visible name for any layers created by this algorithm.
virtual QgsFields outputFields(const QgsFields &inputFields) const
Maps the input source fields (inputFields) to corresponding output fields generated by the algorithm...
virtual bool prepareAlgorithm(const QVariantMap &parameters, QgsProcessingContext &context, QgsProcessingFeedback *feedback) SIP_THROW(QgsProcessingException)
Prepares the algorithm to run using the specified parameters.
Base class for all map layer types.
Definition: qgsmaplayer.h:83
Base class for providing feedback from a processing algorithm.
virtual QgsFeatureList processFeature(const QgsFeature &feature, QgsProcessingContext &context, QgsProcessingFeedback *feedback) SIP_THROW(QgsProcessingException)=0
Processes an individual input feature from the source.
QList< QgsFeature > QgsFeatureList
Definition: qgsfeature.h:583
virtual QString name() const =0
Returns the algorithm name, used for identifying the algorithm.
virtual QString group() const
Returns the name of the group this algorithm belongs to.
Container of fields for a vector layer.
Definition: qgsfields.h:44
virtual QStringList tags() const
Returns a list of tags which relate to the algorithm, and are used to assist users in searching for s...
The feature class encapsulates a single feature including its id, geometry and a list of field/values...
Definition: qgsfeature.h:55
virtual QList< int > inputLayerTypes() const
Returns the valid input layer types for the source layer for this algorithm.
virtual QString shortHelpString() const
Returns a localised short helper string for the algorithm.
virtual QgsFeatureRequest request() const
Returns the feature request used for fetching features to process from the source layer...
This class wraps a request for features to a vector layer (or directly its vector data provider)...
#define SIP_FACTORY
Definition: qgis_sip.h:76
virtual QgsProcessingAlgorithm * createInstance() const =0
Creates a new instance of the algorithm class.
Flag
Flags controlling how QgsProcessingFeatureSource fetches features.
virtual QString displayName() const =0
Returns the translated algorithm name, which should be used for any user-visible display of the algor...
virtual QgsProcessingFeatureSource::Flag sourceFlags() const
Returns the processing feature source flags to be used in the algorithm.
bool supportInPlaceEdit(const QgsMapLayer *layer) const override
Checks whether this algorithm supports in-place editing on the given layer Default implementation for...
virtual void initParameters(const QVariantMap &configuration=QVariantMap())
Initializes any extra parameters added by the algorithm subclass.
virtual QString groupId() const
Returns the unique ID of the group this algorithm belongs to.
QList< int > QgsAttributeList
Definition: qgsfield.h:26
An abstract QgsProcessingAlgorithm base class for processing algorithms which operate "feature-by-fea...
Contains information about the context in which a processing algorithm is executed.