QGIS API Documentation 3.27.0-Master (1d7a28cfd2)
qgsvectorlayerfeaturecounter.h
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1/***************************************************************************
2 qgsvectorlayerfeaturecounter.h
3 ---------------------
4 begin : May 2017
5 copyright : (C) 2017 by Matthias Kuhn
6 email : matthias at opengis dot ch
7 ***************************************************************************
8 * *
9 * This program is free software; you can redistribute it and/or modify *
10 * it under the terms of the GNU General Public License as published by *
11 * the Free Software Foundation; either version 2 of the License, or *
12 * (at your option) any later version. *
13 * *
14 ***************************************************************************/
15#ifndef QGSVECTORLAYERFEATURECOUNTER_H
16#define QGSVECTORLAYERFEATURECOUNTER_H
17
19#include "qgsrenderer.h"
20#include "qgstaskmanager.h"
21#include "qgsfeatureid.h"
22
33class CORE_EXPORT QgsVectorLayerFeatureCounter : public QgsTask
34{
35 Q_OBJECT
36
37 public:
38
45 QgsVectorLayerFeatureCounter( QgsVectorLayer *layer, const QgsExpressionContext &context = QgsExpressionContext(), bool storeSymbolFids = false );
47
51 bool run() override;
52
53 void cancel() override;
54
61 QHash<QString, long long> symbolFeatureCountMap() const SIP_SKIP;
62
67 long long featureCount( const QString &legendKey ) const;
68
77 QHash<QString, QgsFeatureIds> symbolFeatureIdMap() const SIP_SKIP;
78
85 QgsFeatureIds featureIds( const QString &symbolkey ) const;
86
87 signals:
88
92 void symbolsCounted();
93
94 private:
96 std::unique_ptr<QgsFeatureRenderer> mRenderer;
97 QgsExpressionContext mExpressionContext;
98 QHash<QString, long long> mSymbolFeatureCountMap;
99 QHash<QString, QgsFeatureIds> mSymbolFeatureIdMap;
100 std::unique_ptr< QgsFeedback > mFeedback;
101 bool mWithFids = false;
102 long mFeatureCount = 0;
103
104};
105
106#endif // QGSVECTORLAYERFEATURECOUNTER_H
Expression contexts are used to encapsulate the parameters around which a QgsExpression should be eva...
Base class for feedback objects to be used for cancellation of something running in a worker thread.
Definition: qgsfeedback.h:45
Abstract base class for long running background tasks.
virtual bool run()=0
Performs the task's operation.
virtual void cancel()
Notifies the task that it should terminate.
Counts the features in a QgsVectorLayer in task.
~QgsVectorLayerFeatureCounter() override
Partial snapshot of vector layer's state (only the members necessary for access to features)
Represents a vector layer which manages a vector based data sets.
std::unique_ptr< GEOSGeometry, GeosDeleter > unique_ptr
Scoped GEOS pointer.
Definition: qgsgeos.h:74
#define SIP_SKIP
Definition: qgis_sip.h:126
QSet< QgsFeatureId > QgsFeatureIds
Definition: qgsfeatureid.h:37