QGIS API Documentation 3.27.0-Master (1c05421486)
qgsvaluerelationfieldformatter.h
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1/***************************************************************************
2 qgsvaluerelationfieldformatter.h - QgsValueRelationFieldFormatter
3
4 ---------------------
5 begin : 3.12.2016
6 copyright : (C) 2016 by Matthias Kuhn
8 ***************************************************************************
9 * *
10 * This program is free software; you can redistribute it and/or modify *
11 * it under the terms of the GNU General Public License as published by *
12 * the Free Software Foundation; either version 2 of the License, or *
13 * (at your option) any later version. *
14 * *
15 ***************************************************************************/
16#ifndef QGSVALUERELATIONFIELDKIT_H
17#define QGSVALUERELATIONFIELDKIT_H
18
19#include "qgis_core.h"
20#include "qgsfieldformatter.h"
21#include "qgsexpression.h"
23
24#include <QVector>
25#include <QVariant>
26
27
38{
39 public:
41 {
43 ValueRelationItem( const QVariant &key, const QString &value, const QString &description = QString() )
44 : key( key )
45 , value( value )
46 , description( description )
47 {}
48
50 ValueRelationItem() = default;
51
52 QVariant key;
53 QString value;
54 QString description;
55 };
56
57 typedef QVector < QgsValueRelationFieldFormatter::ValueRelationItem > ValueRelationCache;
58
63
64 QString id() const override;
65 QString representValue( QgsVectorLayer *layer, int fieldIndex, const QVariantMap &config, const QVariant &cache, const QVariant &value ) const override;
66
67 QVariant sortValue( QgsVectorLayer *layer, int fieldIndex, const QVariantMap &config, const QVariant &cache, const QVariant &value ) const override;
68
69 QVariant createCache( QgsVectorLayer *layer, int fieldIndex, const QVariantMap &config ) const override;
70
75 static QStringList valueToStringList( const QVariant &value );
76
88 static QgsValueRelationFieldFormatter::ValueRelationCache createCache( const QVariantMap &config, const QgsFeature &formFeature = QgsFeature(), const QgsFeature &parentFormFeature = QgsFeature() );
89
98 static bool expressionRequiresFormScope( const QString &expression );
99
107 static QSet<QString> expressionFormAttributes( const QString &expression );
108
116 static QSet<QString> expressionFormVariables( const QString &expression );
117
126 static bool expressionRequiresParentFormScope( const QString &expression );
127
135 static QSet<QString> expressionParentFormAttributes( const QString &expression );
136
144 static QSet<QString> expressionParentFormVariables( const QString &expression );
145
146
154 static bool expressionIsUsable( const QString &expression, const QgsFeature &feature, const QgsFeature &parentFeature = QgsFeature() );
155
160 static QgsVectorLayer *resolveLayer( const QVariantMap &config, const QgsProject *project );
161
162 QList<QgsVectorLayerRef> layerDependencies( const QVariantMap &config ) const override SIP_SKIP;
163
164 QVariantList availableValues( const QVariantMap &config, int countLimit, const QgsFieldFormatterContext &context ) const override;
165};
166
168
169#endif // QGSVALUERELATIONFIELDKIT_H
The feature class encapsulates a single feature including its unique ID, geometry and a list of field...
Definition: qgsfeature.h:56
A context for field formatter containing information like the project.
A field formatter helps to handle and display values for a field.
virtual QVariant createCache(QgsVectorLayer *layer, int fieldIndex, const QVariantMap &config) const
Create a cache for a given field.
virtual QString id() const =0
Returns a unique id for this field formatter.
virtual QVariantList availableValues(const QVariantMap &config, int countLimit, const QgsFieldFormatterContext &context) const
Returns a list of the values that would be possible to select with this widget type On a RelationRefe...
virtual QVariant sortValue(QgsVectorLayer *layer, int fieldIndex, const QVariantMap &config, const QVariant &cache, const QVariant &value) const
If the default sort order should be overwritten for this widget, you can transform the value in here.
virtual QList< QgsVectorLayerRef > layerDependencies(const QVariantMap &config) const SIP_SKIP
Returns a list of weak layer references to other layers required by this formatter for the given conf...
virtual QString representValue(QgsVectorLayer *layer, int fieldIndex, const QVariantMap &config, const QVariant &cache, const QVariant &value) const
Create a pretty String representation of the value.
Encapsulates a QGIS project, including sets of map layers and their styles, layouts,...
Definition: qgsproject.h:104
Field formatter for a value relation field.
QVector< QgsValueRelationFieldFormatter::ValueRelationItem > ValueRelationCache
Represents a vector layer which manages a vector based data sets.
#define SIP_SKIP
Definition: qgis_sip.h:126
Q_DECLARE_METATYPE(QgsDatabaseQueryLogEntry)
ValueRelationItem()=default
Constructor for ValueRelationItem.
ValueRelationItem(const QVariant &key, const QString &value, const QString &description=QString())
Constructor for ValueRelationItem.