QGIS API Documentation  3.9.0-Master (224899f119)
qgsstoredexpressionmanager.h
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1 /***************************************************************************
2  qgsstoredexpressionmanager.h
3  -------------------
4  begin : August 2019
5  copyright : (C) 2019 David Signer
6  email : david at opengis dot ch
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 QGSSTOREDEXPRESSIONMANAGER_H
19 #define QGSSTOREDEXPRESSIONMANAGER_H
20 
21 #include "qgis_core.h"
22 #include <QString>
23 #include <QObject>
24 #include <QUuid>
25 
26 
27 #ifdef SIP_RUN
28 % ModuleHeaderCode
30 % End
31 #endif
32 
33 class QDomNode;
34 class QDomDocument;
35 
41 struct CORE_EXPORT QgsStoredExpression
42 {
43 
49  enum Category
50  {
51  FilterExpression = 1 << 0,
52  DefaultValueExpression = 1 << 1,
53  All = FilterExpression | DefaultValueExpression
54  };
55 
56 #ifndef SIP_RUN
57 
61  QgsStoredExpression() = default;
62 
70  QgsStoredExpression( QString name, QString expression, Category tag = Category::FilterExpression )
71  : id( QUuid::createUuid().toString() ),
72  name( name ),
73  expression( expression ),
74  tag( tag )
75  {}
76 #endif
77 
79  QString id;
81  QString name;
83  QString expression;
86 };
87 
93 class CORE_EXPORT QgsStoredExpressionManager : public QObject
94 {
95  Q_OBJECT
96 
97  public:
98 
102  QgsStoredExpressionManager() = default;
103 
112  QString addStoredExpression( const QString &name, const QString &expression, const QgsStoredExpression::Category &tag = QgsStoredExpression::Category::FilterExpression );
113 
119  void removeStoredExpression( const QString &id );
120 
129  void updateStoredExpression( const QString &id, const QString &name, const QString &expression, const QgsStoredExpression::Category &tag );
130 
136  void addStoredExpressions( const QList< QgsStoredExpression > &storedExpressions );
137 
143  QList< QgsStoredExpression > storedExpressions( const QgsStoredExpression::Category &tag = QgsStoredExpression::Category::All );
144 
145 
151  QgsStoredExpression storedExpression( const QString &id ) const;
152 
159  QgsStoredExpression findStoredExpressionByExpression( const QString &expression, const QgsStoredExpression::Category &tag = QgsStoredExpression::Category::All ) const;
160 
162  void clearStoredExpressions();
163 
165  bool writeXml( QDomNode &layerNode ) const;
166 
168  bool readXml( const QDomNode &layerNode );
169 
170  signals:
171 
172  public slots:
173 
174  private:
175  QList< QgsStoredExpression > mStoredExpressions;
176 };
177 
178 #endif // QGSSTOREDEXPRESSIONMANAGER_H
Category
Categories of use cases FilterExpression for stored expressions to filter attribute table DefaultValu...
Category tag
category of the expression use case
QString id
generated uuid used for identification
QString expression
expression text
QString name
descriptive name of the expression
QgsStoredExpression(QString name, QString expression, Category tag=Category::FilterExpression)
Create a new QgsStoredExpression with a generated uuid as id.
Stored expression containing name, content (expression text) and a category tag.
Manages stored expressions regarding creation, modification and storing in the project.