QGIS API Documentation 3.27.0-Master (f261cc1f8b)
qgsrelationreferencesearchwidgetwrapper.cpp
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1/***************************************************************************
2 qgsrelationreferencesearchwidgetwrapper.cpp
3 ------------------------------------------
4 Date : 2016-05-25
5 Copyright : (C) 2016 Nyall Dawson
6 Email : nyall dot dawson at gmail dot com
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
17
18#include "qgsfields.h"
20#include "qgsvectorlayer.h"
21#include "qgsproject.h"
23#include "qgsrelationmanager.h"
24#include "qgssettings.h"
25#include "qgsapplication.h"
26
27#include <QStringListModel>
28
30 : QgsSearchWidgetWrapper( vl, fieldIdx, parent )
31 , mCanvas( canvas )
32{
33
34}
35
37{
38 return true;
39}
40
42{
43 return mExpression;
44}
45
47{
48 if ( !mWidget )
49 return QVariant( );
50
51 const QVariantList fkeys = mWidget->foreignKeys();
52
53 if ( fkeys.isEmpty() )
54 {
55 return QVariant( );
56 }
57 else
58 {
59 const QList<QgsRelation::FieldPair> fieldPairs = mWidget->relation().fieldPairs();
60 Q_ASSERT( fieldPairs.count() == fkeys.count() );
61 for ( int i = 0; i < fieldPairs.count(); i++ )
62 {
63 if ( fieldPairs.at( i ).referencingField() == layer()->fields().at( fieldIndex() ).name() )
64 return fkeys.at( i );
65 }
66 return QVariant(); // should not happen
67 }
68}
69
70QgsSearchWidgetWrapper::FilterFlags QgsRelationReferenceSearchWidgetWrapper::supportedFlags() const
71{
73}
74
75QgsSearchWidgetWrapper::FilterFlags QgsRelationReferenceSearchWidgetWrapper::defaultFlags() const
76{
77 return EqualTo;
78}
79
80QString QgsRelationReferenceSearchWidgetWrapper::createExpression( QgsSearchWidgetWrapper::FilterFlags flags ) const
81{
82 const QString fieldName = createFieldIdentifier();
83
84 //clear any unsupported flags
85 flags &= supportedFlags();
86 if ( flags & IsNull )
87 return fieldName + " IS NULL";
88 if ( flags & IsNotNull )
89 return fieldName + " IS NOT NULL";
90
91 const QVariant v = value();
92 if ( !v.isValid() )
93 return QString();
94
95 switch ( v.type() )
96 {
97 case QVariant::Int:
98 case QVariant::UInt:
99 case QVariant::Double:
100 case QVariant::LongLong:
101 case QVariant::ULongLong:
102 {
103 if ( flags & EqualTo )
104 {
105 if ( v.isNull() )
106 return fieldName + " IS NULL";
107 return fieldName + '=' + v.toString();
108 }
109 else if ( flags & NotEqualTo )
110 {
111 if ( v.isNull() )
112 return fieldName + " IS NOT NULL";
113 return fieldName + "<>" + v.toString();
114 }
115 break;
116 }
117
118 default:
119 {
120 if ( flags & EqualTo )
121 return fieldName + "='" + v.toString() + '\'';
122 else if ( flags & NotEqualTo )
123 return fieldName + "<>'" + v.toString() + '\'';
124 break;
125 }
126 }
127
128 return QString();
129}
130
132{
133 if ( mWidget )
134 {
135 mWidget->showIndeterminateState();
136 }
137}
138
140{
141 if ( mWidget )
142 {
143 mWidget->setEnabled( enabled );
144 }
145}
146
148{
149 return true;
150}
151
153{
154 onValuesChanged( QVariantList() << value );
155}
156
157void QgsRelationReferenceSearchWidgetWrapper::onValuesChanged( const QVariantList &values )
158{
159 if ( values.isEmpty() )
160 {
162 emit valueCleared();
163 }
164 else
165 {
166 const QgsSettings settings;
167 // TODO: adapt for composite keys
168 const QVariant value = values.at( 0 );
169 setExpression( value.isNull() ? QgsApplication::nullRepresentation() : value.toString() );
170 emit valueChanged();
171 }
173}
174
176{
177 QString exp = expression;
178 const QString nullValue = QgsApplication::nullRepresentation();
179 const QString fieldName = layer()->fields().at( mFieldIdx ).name();
180
181 QString str;
182 if ( exp == nullValue )
183 {
184 str = QStringLiteral( "%1 IS NULL" ).arg( QgsExpression::quotedColumnRef( fieldName ) );
185 }
186 else
187 {
188 str = QStringLiteral( "%1 = '%3'" )
189 .arg( QgsExpression::quotedColumnRef( fieldName ),
190 exp.replace( '\'', QLatin1String( "''" ) )
191 );
192 }
194}
195
197{
198 return new QgsRelationReferenceWidget( parent );
199}
200
202{
203 mWidget = qobject_cast<QgsRelationReferenceWidget *>( editor );
204 if ( !mWidget )
205 return;
206
207 mWidget->setEditorContext( context(), mCanvas, nullptr );
208
209 mWidget->setEmbedForm( false );
210 mWidget->setReadOnlySelector( false );
211 mWidget->setAllowMapIdentification( config( QStringLiteral( "MapIdentification" ), false ).toBool() );
212 mWidget->setOrderByValue( config( QStringLiteral( "OrderByValue" ), false ).toBool() );
213 mWidget->setAllowAddFeatures( false );
214 mWidget->setOpenFormButtonVisible( false );
215
216 if ( config( QStringLiteral( "FilterFields" ), QVariant() ).isValid() )
217 {
218 mWidget->setFilterFields( config( QStringLiteral( "FilterFields" ) ).toStringList() );
219 mWidget->setChainFilters( config( QStringLiteral( "ChainFilters" ) ).toBool() );
220 mWidget->setFilterExpression( config( QStringLiteral( "FilterExpression" ) ).toString() );
221 }
222
223 QgsRelation relation = QgsProject::instance()->relationManager()->relation( config( QStringLiteral( "Relation" ) ).toString() );
224 // if no relation is given from the config, fetch one if there is only one available
225 if ( !relation.isValid() && !layer()->referencingRelations( mFieldIdx ).isEmpty() && layer()->referencingRelations( mFieldIdx ).count() == 1 )
226 relation = layer()->referencingRelations( mFieldIdx )[0];
227 mWidget->setRelation( relation, config( QStringLiteral( "AllowNULL" ) ).toBool() );
228
229 mWidget->showIndeterminateState();
230 connect( mWidget, &QgsRelationReferenceWidget::foreignKeysChanged, this, &QgsRelationReferenceSearchWidgetWrapper::onValuesChanged );
231}
232
233
static QString nullRepresentation()
This string is used to represent the value NULL throughout QGIS.
static QString quotedColumnRef(QString name)
Returns a quoted column reference (in double quotes)
QString name
Definition: qgsfield.h:60
QgsField at(int i) const
Returns the field at particular index (must be in range 0..N-1).
Definition: qgsfields.cpp:163
Map canvas is a class for displaying all GIS data types on a canvas.
Definition: qgsmapcanvas.h:90
QgsRelationManager * relationManager
Definition: qgsproject.h:114
static QgsProject * instance()
Returns the QgsProject singleton instance.
Definition: qgsproject.cpp:480
Q_INVOKABLE QgsRelation relation(const QString &id) const
Gets access to a relation by its id.
Q_DECL_DEPRECATED void onValueChanged(const QVariant &value)
Called when current value of search widget changes.
void initWidget(QWidget *editor) override
This method should initialize the editor widget with runtime data.
QString expression() const override
Will be used to access the widget's value.
QWidget * createWidget(QWidget *parent) override
This method should create a new widget with the provided parent.
bool applyDirectly() override
If this is true, then this search widget should take effect directly when its expression changes.
QgsRelationReferenceSearchWidgetWrapper(QgsVectorLayer *vl, int fieldIdx, QgsMapCanvas *canvas, QWidget *parent=nullptr)
Constructor for QgsRelationReferenceSearchWidgetWrapper.
QgsSearchWidgetWrapper::FilterFlags supportedFlags() const override
Returns filter flags supported by the search widget.
QVariant value() const
Returns a variant representing the current state of the widget.
QString createExpression(QgsSearchWidgetWrapper::FilterFlags flags) const override
QgsSearchWidgetWrapper::FilterFlags defaultFlags() const override
Returns the default flags (equalTo)
bool valid() const override
Returns true if the widget has been properly initialized.
void setFilterExpression(const QString &filterExpression)
If not empty, will be used as filter expression.
void foreignKeysChanged(const QVariantList &)
Emitted when the foreign keys changed.
void setChainFilters(bool chainFilters)
Set if filters are chained.
void setEditorContext(const QgsAttributeEditorContext &context, QgsMapCanvas *canvas, QgsMessageBar *messageBar)
Sets the editor context.
void showIndeterminateState()
Sets the widget to display in an indeterminate "mixed value" state.
void setFilterFields(const QStringList &filterFields)
Sets the fields for which filter comboboxes will be created.
void setAllowMapIdentification(bool allowMapIdentification)
QgsRelation relation() const
Returns the current relation, which might be invalid.
QVariantList foreignKeys() const
returns the related feature foreign key
void setOrderByValue(bool orderByValue)
Sets if the widget will order the combobox entries by value.
void setRelation(const QgsRelation &relation, bool allowNullValue)
void setOpenFormButtonVisible(bool openFormButtonVisible)
void setAllowAddFeatures(bool allowAddFeatures)
Determines if a button for adding new features should be shown.
QList< QgsRelation::FieldPair > fieldPairs() const
Returns the field pairs which form this relation The first element of each pair are the field names o...
bool isValid
Definition: qgsrelation.h:49
Shows a search widget on a filter form.
@ IsNull
Supports searching for null values.
@ IsNotNull
Supports searching for non-null values.
@ EqualTo
Supports equal to.
@ NotEqualTo
Supports not equal to.
int fieldIndex() const
Returns the field index.
void valueChanged()
Emitted when a user changes the value of the search widget.
void valueCleared()
Emitted when a user changes the value of the search widget back to an empty, default state.
void expressionChanged(const QString &exp)
Emitted whenever the expression changes.
QString createFieldIdentifier() const
Gets a field name or expression to use as field comparison.
void clearExpression()
clears the expression to search for all features
static QString toString(QgsSearchWidgetWrapper::FilterFlag flag)
Returns a translated string representing a filter flag.
This class is a composition of two QSettings instances:
Definition: qgssettings.h:62
Represents a vector layer which manages a vector based data sets.
QgsFields fields() const FINAL
Returns the list of fields of this layer.
QList< QgsRelation > referencingRelations(int idx) const
Returns the layer's relations, where the foreign key is on this layer.
const QgsAttributeEditorContext & context() const
Returns information about the context in which this widget is shown.
QgsVectorLayer * layer() const
Returns the vector layer associated with the widget.
QVariantMap config() const
Returns the whole config.
#define str(x)
Definition: qgis.cpp:37