QGIS API Documentation  3.4.15-Madeira (e83d02e274)
qgsprocessingprovider.h
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1 /***************************************************************************
2  qgsprocessingprovider.h
3  ------------------------
4  begin : December 2016
5  copyright : (C) 2016 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 QGSPROCESSINGPROVIDER_H
19 #define QGSPROCESSINGPROVIDER_H
20 
21 #include "qgis_core.h"
22 #include "qgis.h"
23 #include "qgsprocessingalgorithm.h"
24 #include <QIcon>
25 
34 class CORE_EXPORT QgsProcessingProvider : public QObject
35 {
36  Q_OBJECT
37 
38  public:
39 
43  QgsProcessingProvider( QObject *parent SIP_TRANSFERTHIS = nullptr );
44 
45  ~QgsProcessingProvider() override;
46 
48  QgsProcessingProvider( const QgsProcessingProvider &other ) = delete;
50  QgsProcessingProvider &operator=( const QgsProcessingProvider &other ) = delete;
51 
56  virtual QIcon icon() const;
57 
62  virtual QString svgIconPath() const;
63 
71  virtual QString id() const = 0;
72 
79  virtual QString helpId() const;
80 
87  virtual QString name() const = 0;
88 
99  virtual QString longName() const;
100 
106  virtual bool canBeActivated() const { return true; }
107 
111  virtual bool isActive() const { return true; }
112 
117  virtual QStringList supportedOutputRasterLayerExtensions() const;
118 
126  virtual QStringList supportedOutputVectorLayerExtensions() const;
127 
141  virtual QStringList supportedOutputTableExtensions() const;
142 
150  virtual bool isSupportedOutputValue( const QVariant &outputValue, const QgsProcessingDestinationParameter *parameter, QgsProcessingContext &context, QString &error SIP_OUT ) const;
151 
166  virtual QString defaultVectorFileExtension( bool hasGeometry = true ) const;
167 
179  virtual QString defaultRasterFileExtension() const;
180 
194  virtual bool supportsNonFileBasedOutput() const;
195 
205  virtual bool load() { refreshAlgorithms(); return true; }
206 
211  virtual void unload() {}
212 
216  void refreshAlgorithms();
217 
222  QList< const QgsProcessingAlgorithm * > algorithms() const;
223 
229  const QgsProcessingAlgorithm *algorithm( const QString &name ) const;
230 
231  signals:
232 
238  void algorithmsLoaded();
239 
240  protected:
241 
246  virtual void loadAlgorithms() = 0;
247 
251  bool addAlgorithm( QgsProcessingAlgorithm *algorithm SIP_TRANSFER );
252 
253  private:
254 
255  QMap< QString, const QgsProcessingAlgorithm * > mAlgorithms;
256 
257 #ifdef SIP_RUN
259 #endif
260 };
261 
262 #endif // QGSPROCESSINGPROVIDER_H
263 
264 
virtual bool canBeActivated() const
Returns true if the provider can be activated, or false if it cannot be activated (e...
#define SIP_TRANSFERTHIS
Definition: qgis_sip.h:46
Abstract base class for processing providers.
Base class for all parameter definitions which represent file or layer destinations, e.g.
Abstract base class for processing algorithms.
virtual bool isActive() const
Returns true if the provider is active and able to run algorithms.
#define SIP_TRANSFER
Definition: qgis_sip.h:36
virtual bool load()
Loads the provider.
As part of the API refactoring and improvements which landed in the Processing API was substantially reworked from the x version This was done in order to allow much of the underlying Processing framework to be ported into allowing algorithms to be written in pure substantial changes are required in order to port existing x Processing algorithms for QGIS x The most significant changes are outlined not GeoAlgorithm For algorithms which operate on features one by consider subclassing the QgsProcessingFeatureBasedAlgorithm class This class allows much of the boilerplate code for looping over features from a vector layer to be bypassed and instead requires implementation of a processFeature method Ensure that your algorithm(or algorithm's parent class) implements the new pure virtual createInstance(self) call
#define SIP_OUT
Definition: qgis_sip.h:51
virtual void unload()
Unloads the provider.
Contains information about the context in which a processing algorithm is executed.