QGIS API Documentation 3.27.0-Master (9c08adf5ef)
qgsorderbydialog.cpp
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1/***************************************************************************
2 qgosorderbydialog.cpp
3
4 ---------------------
5 begin : 20.12.2015
6 copyright : (C) 2015 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
17#include "qgsorderbydialog.h"
18
21#include "qgsvectorlayer.h"
22
23#include <QTableWidget>
24#include <QKeyEvent>
25
27 : QDialog( parent )
28 , mLayer( layer )
29{
30 setupUi( this );
31
32 mOrderByTableWidget->horizontalHeader()->setSectionResizeMode( QHeaderView::Stretch );
33 mOrderByTableWidget->horizontalHeader()->setSectionResizeMode( 1, QHeaderView::ResizeToContents );
34 mOrderByTableWidget->horizontalHeader()->setSectionResizeMode( 2, QHeaderView::ResizeToContents );
35
36 mOrderByTableWidget->installEventFilter( this );
37
38 connect( buttonBox, &QDialogButtonBox::helpRequested, this, &QgsOrderByDialog::showHelp );
39}
40
42{
43 mOrderByTableWidget->setRowCount( orderBy.length() + 1 );
44
45 int i = 0;
46 const auto constOrderBy = orderBy;
47 for ( const QgsFeatureRequest::OrderByClause &orderByClause : constOrderBy )
48 {
49 setRow( i, orderByClause );
50
51 ++i;
52 }
53
54 // Add an empty widget at the end
55 setRow( i, QgsFeatureRequest::OrderByClause( QString() ) );
56}
57
59{
61
62 for ( int i = 0; i < mOrderByTableWidget->rowCount(); ++i )
63 {
64 QString expressionText = static_cast<QgsFieldExpressionWidget *>( mOrderByTableWidget->cellWidget( i, 0 ) )->currentText();
65 const bool isExpression = static_cast<QgsFieldExpressionWidget *>( mOrderByTableWidget->cellWidget( i, 0 ) )->isExpression();
66
67 if ( ! expressionText.isEmpty() )
68 {
69 bool asc = true;
70 const int ascIndex = static_cast<QComboBox *>( mOrderByTableWidget->cellWidget( i, 1 ) )->currentIndex();
71 if ( ascIndex == 1 )
72 asc = false;
73
74 bool nullsFirst = false;
75 const int nullsFirstIndex = static_cast<QComboBox *>( mOrderByTableWidget->cellWidget( i, 2 ) )->currentIndex();
76 if ( nullsFirstIndex == 1 )
77 nullsFirst = true;
78
79 if ( !isExpression )
80 expressionText = QgsExpression::quotedColumnRef( expressionText );
81
82 const QgsFeatureRequest::OrderByClause orderByClause( expressionText, asc, nullsFirst );
83
84 orderBy << orderByClause;
85 }
86 }
87
88 return orderBy;
89}
90
91void QgsOrderByDialog::onExpressionChanged( const QString &expression )
92{
93 // The sender() is the field widget which is the cell widget of the first column
94 int row;
95 for ( row = 0; row < mOrderByTableWidget->rowCount(); ++row )
96 {
97 if ( mOrderByTableWidget->cellWidget( row, 0 ) == sender() )
98 {
99 break;
100 }
101 }
102
103 if ( expression.isEmpty() && row != mOrderByTableWidget->rowCount() - 1 )
104 {
105 mOrderByTableWidget->removeRow( row );
106 }
107 else if ( !expression.isEmpty() && row == mOrderByTableWidget->rowCount() - 1 )
108 {
109 mOrderByTableWidget->insertRow( mOrderByTableWidget->rowCount() );
110 setRow( row + 1, QgsFeatureRequest::OrderByClause( QString() ) );
111 }
112}
113
114void QgsOrderByDialog::setRow( int row, const QgsFeatureRequest::OrderByClause &orderByClause )
115{
116 QgsFieldExpressionWidget *fieldExpression = new QgsFieldExpressionWidget();
117 fieldExpression->setLayer( mLayer );
118 fieldExpression->setField( orderByClause.expression().expression() );
119 connect( fieldExpression, static_cast < void ( QgsFieldExpressionWidget::* )( const QString & ) >( &QgsFieldExpressionWidget::fieldChanged ), this, &QgsOrderByDialog::onExpressionChanged );
120
121 QComboBox *ascComboBox = new QComboBox();
122 ascComboBox->addItem( tr( "Ascending" ) );
123 ascComboBox->addItem( tr( "Descending" ) );
124 ascComboBox->setCurrentIndex( orderByClause.ascending() ? 0 : 1 );
125
126 QComboBox *nullsFirstComboBox = new QComboBox();
127 nullsFirstComboBox->addItem( tr( "NULLs Last" ) );
128 nullsFirstComboBox->addItem( tr( "NULLs First" ) );
129 nullsFirstComboBox->setCurrentIndex( orderByClause.nullsFirst() ? 1 : 0 );
130
131 mOrderByTableWidget->setCellWidget( row, 0, fieldExpression );
132 mOrderByTableWidget->setCellWidget( row, 1, ascComboBox );
133 mOrderByTableWidget->setCellWidget( row, 2, nullsFirstComboBox );
134}
135
136bool QgsOrderByDialog::eventFilter( QObject *obj, QEvent *e )
137{
138 Q_UNUSED( obj )
139 Q_ASSERT( obj == mOrderByTableWidget );
140
141 if ( e->type() == QEvent::KeyPress )
142 {
143 QKeyEvent *keyEvent = static_cast<QKeyEvent *>( e );
144
145 if ( keyEvent->key() == Qt::Key_Delete )
146 {
147 if ( mOrderByTableWidget->currentRow() != mOrderByTableWidget->rowCount() - 1 )
148 mOrderByTableWidget->removeRow( mOrderByTableWidget->currentRow() );
149 return true;
150 }
151 }
152
153 return QDialog::eventFilter( obj, e );
154}
155
156void QgsOrderByDialog::showHelp()
157{
158 QgsHelp::openHelp( QStringLiteral( "working_with_vector/vector_properties.html#layer-rendering" ) );
159}
QString expression() const
Returns the original, unmodified expression string.
static QString quotedColumnRef(QString name)
Returns a quoted column reference (in double quotes)
The OrderByClause class represents an order by clause for a QgsFeatureRequest.
QgsExpression expression() const
The expression.
bool ascending() const
Order ascending.
bool nullsFirst() const
Set if NULLS should be returned first.
Represents a list of OrderByClauses, with the most important first and the least important last.
The QgsFieldExpressionWidget class reates a widget to choose fields and edit expressions It contains ...
void setField(const QString &fieldName)
sets the current field or expression in the widget
void setLayer(QgsMapLayer *layer)
Sets the layer used to display the fields and expression.
void fieldChanged(const QString &fieldName)
Emitted when the currently selected field changes.
static void openHelp(const QString &key)
Opens help topic for the given help key using default system web browser.
Definition: qgshelp.cpp:36
bool eventFilter(QObject *obj, QEvent *e) override
void setOrderBy(const QgsFeatureRequest::OrderBy &orderBy)
Set the order by to manage.
QgsOrderByDialog(QgsVectorLayer *layer, QWidget *parent=nullptr)
Create a new order by dialog.
QgsFeatureRequest::OrderBy orderBy()
Gets the order by defined in the dialog.
Represents a vector layer which manages a vector based data sets.