QGIS API Documentation 3.27.0-Master (1d7a28cfd2)
qgsexpressionselectiondialog.cpp
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1/***************************************************************************
2 qgisexpressionselectiondialog.cpp
3 --------------------------------------
4 Date : 24.1.2013
5 Copyright : (C) 2013 by Matthias kuhn
6 Email : matthias at opengis dot ch
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 "qgsapplication.h"
19#include "qgsexpression.h"
20#include "qgsgeometry.h"
21#include "qgsmapcanvas.h"
22#include "qgsmessagebar.h"
23#include "qgsvectorlayer.h"
24#include "qgssettings.h"
25#include "qgsgui.h"
27
28
29QgsExpressionSelectionDialog::QgsExpressionSelectionDialog( QgsVectorLayer *layer, const QString &startText, QWidget *parent )
30 : QDialog( parent )
31 , mLayer( layer )
32
33{
34 setupUi( this );
35
37
38 connect( mActionSelect, &QAction::triggered, this, &QgsExpressionSelectionDialog::mActionSelect_triggered );
39 connect( mActionAddToSelection, &QAction::triggered, this, &QgsExpressionSelectionDialog::mActionAddToSelection_triggered );
40 connect( mActionRemoveFromSelection, &QAction::triggered, this, &QgsExpressionSelectionDialog::mActionRemoveFromSelection_triggered );
41 connect( mActionSelectIntersect, &QAction::triggered, this, &QgsExpressionSelectionDialog::mActionSelectIntersect_triggered );
42 connect( mButtonZoomToFeatures, &QToolButton::clicked, this, &QgsExpressionSelectionDialog::mButtonZoomToFeatures_clicked );
43 connect( mPbnClose, &QPushButton::clicked, this, &QgsExpressionSelectionDialog::mPbnClose_clicked );
44 connect( mLayer, &QgsVectorLayer::willBeDeleted, this, &QgsExpressionSelectionDialog::close );
45
46 setWindowTitle( tr( "%1 — Select by Expression" ).arg( layer->name() ) );
47
48 mActionSelect->setIcon( QgsApplication::getThemeIcon( QStringLiteral( "/mIconExpressionSelect.svg" ) ) );
49 mActionAddToSelection->setIcon( QgsApplication::getThemeIcon( QStringLiteral( "/mIconSelectAdd.svg" ) ) );
50 mActionRemoveFromSelection->setIcon( QgsApplication::getThemeIcon( QStringLiteral( "/mIconSelectRemove.svg" ) ) );
51 mActionSelectIntersect->setIcon( QgsApplication::getThemeIcon( QStringLiteral( "/mIconSelectIntersect.svg" ) ) );
52
53 mButtonSelect->addAction( mActionSelect );
54 mButtonSelect->addAction( mActionAddToSelection );
55 mButtonSelect->addAction( mActionRemoveFromSelection );
56 mButtonSelect->addAction( mActionSelectIntersect );
57 mButtonSelect->setDefaultAction( mActionSelect );
58
60 mExpressionBuilder->initWithLayer( layer, context, QStringLiteral( "selection" ) );
61 mExpressionBuilder->setExpressionText( startText );
62
63 // by default, zoom to features is hidden, shown only if canvas is set
64 mButtonZoomToFeatures->setVisible( false );
65
66 connect( buttonBox, &QDialogButtonBox::helpRequested, this, &QgsExpressionSelectionDialog::showHelp );
67}
68
70{
71 return mExpressionBuilder;
72}
73
75{
76 mExpressionBuilder->setExpressionText( text );
77}
78
80{
81 return mExpressionBuilder->expressionText();
82}
83
85{
86 // Store in child widget only.
87 mExpressionBuilder->setGeomCalculator( da );
88}
89
91{
92 mMessageBar = messageBar;
93}
94
96{
97 mMapCanvas = canvas;
98 mButtonZoomToFeatures->setVisible( true );
99}
100
101void QgsExpressionSelectionDialog::mActionSelect_triggered()
102{
103 mLayer->selectByExpression( mExpressionBuilder->expressionText(),
105 pushSelectedFeaturesMessage();
106 saveRecent();
107}
108
109void QgsExpressionSelectionDialog::mActionAddToSelection_triggered()
110{
111 mLayer->selectByExpression( mExpressionBuilder->expressionText(),
113 pushSelectedFeaturesMessage();
114 saveRecent();
115}
116
117void QgsExpressionSelectionDialog::mActionSelectIntersect_triggered()
118{
119 mLayer->selectByExpression( mExpressionBuilder->expressionText(),
121 pushSelectedFeaturesMessage();
122 saveRecent();
123}
124
125void QgsExpressionSelectionDialog::mActionRemoveFromSelection_triggered()
126{
127 mLayer->selectByExpression( mExpressionBuilder->expressionText(),
129 pushSelectedFeaturesMessage();
130 saveRecent();
131}
132
133void QgsExpressionSelectionDialog::pushSelectedFeaturesMessage()
134{
135 if ( !mMessageBar )
136 return;
137
138 const int count = mLayer->selectedFeatureCount();
139 if ( count > 0 )
140 {
141 mMessageBar->pushMessage( QString(),
142 tr( "%n matching feature(s) selected", "matching features", count ),
143 Qgis::MessageLevel::Info );
144 }
145 else
146 {
147 mMessageBar->pushMessage( QString(),
148 tr( "No matching features found" ),
149 Qgis::MessageLevel::Info );
150 }
151}
152
153void QgsExpressionSelectionDialog::mButtonZoomToFeatures_clicked()
154{
155 if ( mExpressionBuilder->expressionText().isEmpty() || !mMapCanvas )
156 return;
157
159
160 const QgsFeatureRequest request = QgsFeatureRequest().setFilterExpression( mExpressionBuilder->expressionText() )
161 .setExpressionContext( context )
163
164 QgsFeatureIterator features = mLayer->getFeatures( request );
165
166 QgsRectangle bbox;
167 bbox.setMinimal();
168 QgsFeature feat;
169 int featureCount = 0;
170 while ( features.nextFeature( feat ) )
171 {
172 const QgsGeometry geom = feat.geometry();
173 if ( geom.isNull() || geom.constGet()->isEmpty() )
174 continue;
175
176 const QgsRectangle r = mMapCanvas->mapSettings().layerExtentToOutputExtent( mLayer, geom.boundingBox() );
177 bbox.combineExtentWith( r );
178 featureCount++;
179 }
180 features.close();
181
182 if ( featureCount > 0 )
183 {
184 mMapCanvas->zoomToFeatureExtent( bbox );
185 if ( mMessageBar )
186 {
187 mMessageBar->pushMessage( QString(),
188 tr( "Zoomed to %n matching feature(s)", "number of matching features", featureCount ),
189 Qgis::MessageLevel::Info );
190 }
191 }
192 else if ( mMessageBar )
193 {
194 mMessageBar->pushMessage( QString(),
195 tr( "No matching features found" ),
196 Qgis::MessageLevel::Info );
197 }
198 saveRecent();
199}
200
201void QgsExpressionSelectionDialog::closeEvent( QCloseEvent *closeEvent )
202{
203 QDialog::closeEvent( closeEvent );
204}
205
206void QgsExpressionSelectionDialog::mPbnClose_clicked()
207{
208 close();
209}
210
212{
213 QDialog::done( r );
214 close();
215}
216
217void QgsExpressionSelectionDialog::saveRecent()
218{
219 mExpressionBuilder->expressionTree()->saveToRecent( mExpressionBuilder->expressionText(), QStringLiteral( "selection" ) );
220}
221
222void QgsExpressionSelectionDialog::showHelp()
223{
224 QgsHelp::openHelp( QStringLiteral( "introduction/general_tools.html#automatic-selection" ) );
225}
@ SetSelection
Set selection, removing any existing selection.
@ AddToSelection
Add selection to current selection.
@ IntersectSelection
Modify current selection to include only select features which match.
@ RemoveFromSelection
Remove from current selection.
virtual bool isEmpty() const
Returns true if the geometry is empty.
static QIcon getThemeIcon(const QString &name, const QColor &fillColor=QColor(), const QColor &strokeColor=QColor())
Helper to get a theme icon.
A general purpose distance and area calculator, capable of performing ellipsoid based calculations.
A reusable widget that can be used to build a expression string.
static QList< QgsExpressionContextScope * > globalProjectLayerScopes(const QgsMapLayer *layer)
Creates a list of three scopes: global, layer's project and layer.
Expression contexts are used to encapsulate the parameters around which a QgsExpression should be eva...
QgsExpressionBuilderWidget * expressionBuilder()
The builder widget that is used by the dialog.
QString expressionText()
Returns the current expression text.
void closeEvent(QCloseEvent *closeEvent) override
Implementation for closeEvent Saves the window geometry.
void setExpressionText(const QString &text)
Sets the current expression text.
QgsExpressionSelectionDialog(QgsVectorLayer *layer, const QString &startText=QString(), QWidget *parent=nullptr)
Creates a new selection dialog.
void setMapCanvas(QgsMapCanvas *canvas)
Sets a map canvas associated with the dialog.
void setMessageBar(QgsMessageBar *messageBar)
Sets the message bar to display feedback from the dialog.
void setGeomCalculator(const QgsDistanceArea &da)
Sets geometry calculator used in distance/area calculations.
void done(int r) override
Implementation for done (default behavior when pressing esc) Calls close, so the window geometry gets...
Wrapper for iterator of features from vector data provider or vector layer.
bool nextFeature(QgsFeature &f)
This class wraps a request for features to a vector layer (or directly its vector data provider).
QgsFeatureRequest & setFilterExpression(const QString &expression)
Set the filter expression.
QgsFeatureRequest & setExpressionContext(const QgsExpressionContext &context)
Sets the expression context used to evaluate filter expressions.
QgsFeatureRequest & setNoAttributes()
Set that no attributes will be fetched.
The feature class encapsulates a single feature including its unique ID, geometry and a list of field...
Definition: qgsfeature.h:56
QgsGeometry geometry
Definition: qgsfeature.h:67
A geometry is the spatial representation of a feature.
Definition: qgsgeometry.h:164
const QgsAbstractGeometry * constGet() const SIP_HOLDGIL
Returns a non-modifiable (const) reference to the underlying abstract geometry primitive.
Q_GADGET bool isNull
Definition: qgsgeometry.h:166
QgsRectangle boundingBox() const
Returns the bounding box of the geometry.
static void enableAutoGeometryRestore(QWidget *widget, const QString &key=QString())
Register the widget to allow its position to be automatically saved and restored when open and closed...
Definition: qgsgui.cpp:178
static void openHelp(const QString &key)
Opens help topic for the given help key using default system web browser.
Definition: qgshelp.cpp:36
Map canvas is a class for displaying all GIS data types on a canvas.
Definition: qgsmapcanvas.h:90
void zoomToFeatureExtent(QgsRectangle &rect)
Zooms to feature extent.
const QgsMapSettings & mapSettings() const
Gets access to properties used for map rendering.
QString name
Definition: qgsmaplayer.h:76
void willBeDeleted()
Emitted in the destructor when the layer is about to be deleted, but it is still in a perfectly valid...
QgsRectangle layerExtentToOutputExtent(const QgsMapLayer *layer, QgsRectangle extent) const
transform bounding box from layer's CRS to output CRS
A bar for displaying non-blocking messages to the user.
Definition: qgsmessagebar.h:61
void pushMessage(const QString &text, Qgis::MessageLevel level=Qgis::MessageLevel::Info, int duration=-1)
A convenience method for pushing a message with the specified text to the bar.
A rectangle specified with double values.
Definition: qgsrectangle.h:42
void setMinimal() SIP_HOLDGIL
Set a rectangle so that min corner is at max and max corner is at min.
Definition: qgsrectangle.h:172
void combineExtentWith(const QgsRectangle &rect)
Expands the rectangle so that it covers both the original rectangle and the given rectangle.
Definition: qgsrectangle.h:391
Represents a vector layer which manages a vector based data sets.
QgsFeatureIterator getFeatures(const QgsFeatureRequest &request=QgsFeatureRequest()) const FINAL
Queries the layer for features specified in request.
int selectedFeatureCount() const
Returns the number of features that are selected in this layer.
Q_INVOKABLE void selectByExpression(const QString &expression, Qgis::SelectBehavior behavior=Qgis::SelectBehavior::SetSelection, QgsExpressionContext *context=nullptr)
Selects matching features using an expression.