QGIS API Documentation 3.27.0-Master (75dc696944)
qgsexpressionfieldbuffer.h
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1/***************************************************************************
2 qgsexpressionfieldbuffer.h
3 ---------------------------
4 begin : May 27, 2014
5 copyright : (C) 2014 by Matthias Kuhn
6 email : matthias 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 QGSEXPRESSIONFIELDBUFFER_H
19#define QGSEXPRESSIONFIELDBUFFER_H
20
21#include "qgis_core.h"
22#include <QString>
23#include <QList>
24#include <QDomNode>
25
26#include "qgsfields.h"
27#include "qgsexpression.h"
28
35class CORE_EXPORT QgsExpressionFieldBuffer
36{
37 public:
39 {
40 ExpressionField( const QString &exp, const QgsField &fld )
41 : cachedExpression( exp )
42 , field( fld )
43 {}
44
47 };
48
53
60 void addExpression( const QString &exp, const QgsField &fld );
61
67 void removeExpression( int index );
68
77 void renameExpression( int index, const QString &name );
78
87 void updateExpression( int index, const QString &exp );
88
92 void writeXml( QDomNode &layer_node, QDomDocument &document ) const;
93
97 void readXml( const QDomNode &layer_node );
98
104 void updateFields( QgsFields &flds ) const;
105
106 QList<QgsExpressionFieldBuffer::ExpressionField> expressions() const { return mExpressions; }
107
108 private:
109 QList<ExpressionField> mExpressions;
110};
111
112#endif // QGSEXPRESSIONFIELDBUFFER_H
Buffers information about expression fields for a vector layer.
QList< QgsExpressionFieldBuffer::ExpressionField > expressions() const
QgsExpressionFieldBuffer()=default
Constructor for QgsExpressionFieldBuffer.
Class for parsing and evaluation of expressions (formerly called "search strings").
Encapsulate a field in an attribute table or data source.
Definition: qgsfield.h:51
Container of fields for a vector layer.
Definition: qgsfields.h:45
const QgsField & field
Definition: qgsfield.h:463
ExpressionField(const QString &exp, const QgsField &fld)