QGIS API Documentation  3.4.15-Madeira (e83d02e274)
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.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 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:63
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.
virtual QgsProcessingFeatureSource::Flag sourceFlags() const
Returns the processing feature source flags to be used in the algorithm.
QList< QgsFeature > QgsFeatureList
Definition: qgsfeature.h:571
virtual QString name() const =0
Returns the algorithm name, used for identifying the algorithm.
Container of fields for a vector layer.
Definition: qgsfields.h:42
The feature class encapsulates a single feature including its id, geometry and a list of field/values...
Definition: qgsfeature.h:55
virtual QStringList tags() const
Returns a list of tags which relate to the algorithm, and are used to assist users in searching for s...
This class wraps a request for features to a vector layer (or directly its vector data provider)...
#define SIP_FACTORY
Definition: qgis_sip.h:69
virtual QgsProcessingAlgorithm * createInstance() const =0
Creates a new instance of the algorithm class.
virtual QgsFields outputFields(const QgsFields &inputFields) const
Maps the input source fields (inputFields) to corresponding output fields generated by the algorithm...
Flag
Flags controlling how QgsProcessingFeatureSource fetches features.
virtual QgsFeatureRequest request() const
Returns the feature request used for fetching features to process from the source layer...
virtual QString groupId() const
Returns the unique ID of the group this algorithm belongs to.
virtual QString displayName() const =0
Returns the translated algorithm name, which should be used for any user-visible display of the algor...
virtual QString group() const
Returns the name of the group this algorithm belongs to.
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 QList< int > inputLayerTypes() const
Returns the valid input layer types for the source layer for this algorithm.
QList< int > QgsAttributeList
Definition: qgsfield.h:27
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.
virtual QString shortHelpString() const
Returns a localised short helper string for the algorithm.