QGIS API Documentation  3.26.3-Buenos Aires (65e4edfdad)
qgsalgorithmdropfields.h
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1 /***************************************************************************
2  qgsalgorithmdropfields.h
3  ---------------------------------
4  begin : November 2020
5  copyright : (C) 2020 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 QGSALGORITHMDROPFIELDS_H
19 #define QGSALGORITHMDROPFIELDS_H
20 
21 #define SIP_NO_FILE
22 
23 #include "qgis_sip.h"
24 #include "qgsprocessingalgorithm.h"
25 
27 
31 class QgsDropTableFieldsAlgorithm : public QgsProcessingFeatureBasedAlgorithm
32 {
33 
34  public:
35 
36  QgsDropTableFieldsAlgorithm() = default;
37  QgsProcessingAlgorithm::Flags flags() const override;
38  QString name() const override;
39  QString displayName() const override;
40  QStringList tags() const override;
41  QString group() const override;
42  QString groupId() const override;
43  QString shortHelpString() const override;
44  QString shortDescription() const override;
45  QList<int> inputLayerTypes() const override;
46  QgsDropTableFieldsAlgorithm *createInstance() const override SIP_FACTORY;
47 
48  protected:
49 
50  void initParameters( const QVariantMap &configuration = QVariantMap() ) override;
51  QString outputName() const override;
52  QgsFields outputFields( const QgsFields &inputFields ) const override;
54 
55  bool prepareAlgorithm( const QVariantMap &parameters, QgsProcessingContext &context, QgsProcessingFeedback *feedback ) override;
56  QgsFeatureList processFeature( const QgsFeature &feature, QgsProcessingContext &context, QgsProcessingFeedback *feedback ) override;
57  bool supportInPlaceEdit( const QgsMapLayer *layer ) const override;
58 
59  private:
60 
61  QStringList mFieldsToDelete;
62  mutable QList< int > mFieldIndices;
63 };
64 
65 
69 class QgsRetainTableFieldsAlgorithm : public QgsProcessingFeatureBasedAlgorithm
70 {
71 
72  public:
73 
74  QgsRetainTableFieldsAlgorithm() = default;
75  QgsProcessingAlgorithm::Flags flags() const override;
76  QString name() const override;
77  QString displayName() const override;
78  QStringList tags() const override;
79  QString group() const override;
80  QString groupId() const override;
81  QString shortHelpString() const override;
82  QString shortDescription() const override;
83  QList<int> inputLayerTypes() const override;
84  QgsRetainTableFieldsAlgorithm *createInstance() const override SIP_FACTORY;
85 
86  protected:
87 
88  void initParameters( const QVariantMap &configuration = QVariantMap() ) override;
89  QString outputName() const override;
90  QgsFields outputFields( const QgsFields &inputFields ) const override;
91  QgsProcessingFeatureSource::Flag sourceFlags() const override;
92 
93  bool prepareAlgorithm( const QVariantMap &parameters, QgsProcessingContext &context, QgsProcessingFeedback *feedback ) override;
94  QgsFeatureList processFeature( const QgsFeature &feature, QgsProcessingContext &context, QgsProcessingFeedback *feedback ) override;
95  bool supportInPlaceEdit( const QgsMapLayer *layer ) const override;
96 
97  private:
98 
99  QStringList mFieldsToRetain;
100  mutable QList< int > mFieldIndices;
101 };
102 
103 
105 
106 #endif // QGSALGORITHMDROPFIELDS_H
QgsProcessingAlgorithm::shortDescription
virtual QString shortDescription() const
Returns an optional translated short description of the algorithm.
Definition: qgsprocessingalgorithm.cpp:60
QgsProcessingAlgorithm::displayName
virtual QString displayName() const =0
Returns the translated algorithm name, which should be used for any user-visible display of the algor...
QgsProcessingFeedback
Base class for providing feedback from a processing algorithm.
Definition: qgsprocessingfeedback.h:37
QgsFields
Container of fields for a vector layer.
Definition: qgsfields.h:44
QgsProcessingFeatureBasedAlgorithm::initParameters
virtual void initParameters(const QVariantMap &configuration=QVariantMap())
Initializes any extra parameters added by the algorithm subclass.
Definition: qgsprocessingalgorithm.cpp:1070
QgsProcessingAlgorithm::groupId
virtual QString groupId() const
Returns the unique ID of the group this algorithm belongs to.
Definition: qgsprocessingalgorithm.h:234
QgsProcessingAlgorithm::createInstance
virtual QgsProcessingAlgorithm * createInstance() const =0
Creates a new instance of the algorithm class.
QgsProcessingFeatureBasedAlgorithm::supportInPlaceEdit
bool supportInPlaceEdit(const QgsMapLayer *layer) const override
Checks whether this algorithm supports in-place editing on the given layer Default implementation for...
Definition: qgsprocessingalgorithm.cpp:1139
QgsProcessingAlgorithm::prepareAlgorithm
virtual bool prepareAlgorithm(const QVariantMap &parameters, QgsProcessingContext &context, QgsProcessingFeedback *feedback) SIP_THROW(QgsProcessingException)
Prepares the algorithm to run using the specified parameters.
Definition: qgsprocessingalgorithm.cpp:451
QgsProcessingFeatureBasedAlgorithm
An abstract QgsProcessingAlgorithm base class for processing algorithms which operate "feature-by-fea...
Definition: qgsprocessingalgorithm.h:1143
QgsProcessingFeatureBasedAlgorithm::sourceFlags
virtual QgsProcessingFeatureSource::Flag sourceFlags() const
Returns the processing feature source flags to be used in the algorithm.
Definition: qgsprocessingalgorithm.cpp:1045
SIP_FACTORY
#define SIP_FACTORY
Definition: qgis_sip.h:76
QgsProcessingAlgorithm::name
virtual QString name() const =0
Returns the algorithm name, used for identifying the algorithm.
QgsProcessingFeatureBasedAlgorithm::processFeature
virtual QgsFeatureList processFeature(const QgsFeature &feature, QgsProcessingContext &context, QgsProcessingFeedback *feedback) SIP_THROW(QgsProcessingException)=0
Processes an individual input feature from the source.
QgsProcessingContext
Contains information about the context in which a processing algorithm is executed.
Definition: qgsprocessingcontext.h:46
qgsprocessingalgorithm.h
QgsProcessingFeatureBasedAlgorithm::flags
QgsProcessingAlgorithm::Flags flags() const override
Returns the flags indicating how and when the algorithm operates and should be exposed to users.
Definition: qgsprocessingalgorithm.cpp:1011
qgis_sip.h
QgsFeatureList
QList< QgsFeature > QgsFeatureList
Definition: qgsfeature.h:882
QgsProcessingAlgorithm::shortHelpString
virtual QString shortHelpString() const
Returns a localised short helper string for the algorithm.
Definition: qgsprocessingalgorithm.cpp:65
QgsProcessingFeatureBasedAlgorithm::outputName
virtual QString outputName() const =0
Returns the translated, user visible name for any layers created by this algorithm.
QgsProcessingFeatureBasedAlgorithm::outputFields
virtual QgsFields outputFields(const QgsFields &inputFields) const
Maps the input source fields (inputFields) to corresponding output fields generated by the algorithm.
Definition: qgsprocessingalgorithm.cpp:1060
QgsProcessingFeatureSource::Flag
Flag
Flags controlling how QgsProcessingFeatureSource fetches features.
Definition: qgsprocessingutils.h:582
QgsMapLayer
Base class for all map layer types. This is the base class for all map layer types (vector,...
Definition: qgsmaplayer.h:72
QgsProcessingFeatureSource
QgsFeatureSource subclass which proxies methods to an underlying QgsFeatureSource,...
Definition: qgsprocessingutils.h:577
QgsProcessingAlgorithm::group
virtual QString group() const
Returns the name of the group this algorithm belongs to.
Definition: qgsprocessingalgorithm.h:225
QgsFeature
The feature class encapsulates a single feature including its unique ID, geometry and a list of field...
Definition: qgsfeature.h:55
QgsProcessingFeatureBasedAlgorithm::inputLayerTypes
virtual QList< int > inputLayerTypes() const
Returns the valid input layer types for the source layer for this algorithm.
Definition: qgsprocessingalgorithm.cpp:1035
QgsProcessingAlgorithm::tags
virtual QStringList tags() const
Returns a list of tags which relate to the algorithm, and are used to assist users in searching for s...
Definition: qgsprocessingalgorithm.h:181