[FEATURE] Add zoom to features shortcut in select by form dialog

Allows very quick navigation to features which match the criteria
in the form

python/gui/qgsattributeform.sip

@@ -164,6 +164,12 @@ class QgsAttributeForm : QWidget
      */
     void closed();
 
+    /**
+     * Emitted when the user chooses to zoom to a filtered set of features.
+     * @note added in QGIS 3.0
+     */
+    void zoomToFeatures( const QString& filter );
+
   public slots:
     /**
      * Call this to change the content of a given attribute. Will update the editor(s) related to this field.

python/gui/qgsmapcanvas.sip

@@ -231,6 +231,10 @@ class QgsMapCanvas : QGraphicsView
     //! Zooms in/out with a given center
     void zoomWithCenter( int x, int y, bool zoomIn );
 
+    //! Zooms to feature extent. Adds a small margin around the extent
+    //! and does a pan if rect is empty (point extent)
+    void zoomToFeatureExtent( QgsRectangle& rect );
+
     //! Returns whether the scale is locked, so zooming can be performed using magnication.
     //! @note added in 2.16
     //! @see setScaleLocked()
@@ -518,10 +522,6 @@ class QgsMapCanvas : QGraphicsView
     //! called when panning is in action, reset indicates end of panning
     void moveCanvasContents( bool reset = false );
 
-    //! Zooms to feature extent. Adds a small margin around the extent
-    //! and does a pan if rect is empty (point extent)
-    void zoomToFeatureExtent( QgsRectangle& rect );
-
     //! called on resize or changed extent to notify canvas items to change their rectangle
     void updateCanvasItemPositions();
 

src/app/qgisapp.cpp

@@ -7520,6 +7520,7 @@ void QgisApp::selectByForm()
 
   QgsSelectByFormDialog* dlg = new QgsSelectByFormDialog( vlayer, context, this );
   dlg->setMessageBar( messageBar() );
+  dlg->setMapCanvas( mapCanvas() );
   dlg->setAttribute( Qt::WA_DeleteOnClose );
   dlg->show();
 }

src/app/qgsselectbyformdialog.cpp

@@ -15,11 +15,14 @@
 
 #include "qgsselectbyformdialog.h"
 #include "qgsattributeform.h"
+#include "qgsmapcanvas.h"
 #include <QLayout>
 #include <QSettings>
 
 QgsSelectByFormDialog::QgsSelectByFormDialog( QgsVectorLayer* layer, const QgsAttributeEditorContext& context, QWidget* parent, Qt::WindowFlags fl )
     : QDialog( parent, fl )
+    , mLayer( layer )
+    , mMessageBar( nullptr )
 {
   QgsAttributeEditorContext dlgContext = context;
   dlgContext.setFormMode( QgsAttributeEditorContext::StandaloneDialog );
@@ -51,5 +54,66 @@ QgsSelectByFormDialog::~QgsSelectByFormDialog()
 
 void QgsSelectByFormDialog::setMessageBar( QgsMessageBar* messageBar )
 {
+  mMessageBar = messageBar;
   mForm->setMessageBar( messageBar );
 }
+
+void QgsSelectByFormDialog::setMapCanvas( QgsMapCanvas* canvas )
+{
+  mMapCanvas = canvas;
+  connect( mForm, &QgsAttributeForm::zoomToFeatures, this, &QgsSelectByFormDialog::zoomToFeatures );
+}
+
+void QgsSelectByFormDialog::zoomToFeatures( const QString& filter )
+{
+  QgsFeatureIds ids;
+
+  QgsExpressionContext context;
+  context << QgsExpressionContextUtils::globalScope()
+  << QgsExpressionContextUtils::projectScope()
+  << QgsExpressionContextUtils::layerScope( mLayer );
+
+  QgsFeatureRequest request = QgsFeatureRequest().setFilterExpression( filter )
+                              .setExpressionContext( context )
+                              .setSubsetOfAttributes( QgsAttributeList() );
+
+  QgsFeatureIterator features = mLayer->getFeatures( request );
+
+  QgsRectangle bbox;
+  bbox.setMinimal();
+  QgsFeature feat;
+  int featureCount = 0;
+  while ( features.nextFeature( feat ) )
+  {
+    QgsGeometry geom = feat.geometry();
+    if ( geom.isEmpty() || geom.geometry()->isEmpty() )
+      continue;
+
+    QgsRectangle r = mMapCanvas->mapSettings().layerExtentToOutputExtent( mLayer, geom.boundingBox() );
+    bbox.combineExtentWith( r );
+    featureCount++;
+  }
+  features.close();
+
+  QSettings settings;
+  int timeout = settings.value( QStringLiteral( "/qgis/messageTimeout" ), 5 ).toInt();
+  if ( featureCount > 0 )
+  {
+    mMapCanvas->zoomToFeatureExtent( bbox );
+    if ( mMessageBar )
+    {
+      mMessageBar->pushMessage( QString(),
+                                tr( "Zoomed to %1 matching %2" ).arg( featureCount )
+                                .arg( featureCount == 1 ? tr( "feature" ) : tr( "features" ) ),
+                                QgsMessageBar::INFO,
+                                timeout );
+    }
+  }
+  else if ( mMessageBar )
+  {
+    mMessageBar->pushMessage( QString(),
+                              tr( "No matching features found" ),
+                              QgsMessageBar::INFO,
+                              timeout );
+  }
+}

src/app/qgsselectbyformdialog.h

@@ -22,6 +22,7 @@
 class QgsAttributeForm;
 class QgsMessageBar;
 class QgsVectorLayer;
+class QgsMapCanvas;
 
 /** \ingroup app
  * \class QgsSelectByFormDialog
@@ -54,9 +55,21 @@ class APP_EXPORT QgsSelectByFormDialog : public QDialog
      */
     void setMessageBar( QgsMessageBar* messageBar );
 
+    /**
+     * Sets a map canvas associated with the dialog.
+     */
+    void setMapCanvas( QgsMapCanvas* canvas );
+
+  private slots:
+
+    void zoomToFeatures( const QString& filter );
+
   private:
 
     QgsAttributeForm* mForm;
+    QgsVectorLayer* mLayer;
+    QgsMessageBar* mMessageBar;
+    QgsMapCanvas* mMapCanvas;
 
 };
 

src/gui/qgsattributeform.cpp

@@ -405,6 +405,15 @@ void QgsAttributeForm::filterTriggered()
     setMode( SingleEditMode );
 }
 
+void QgsAttributeForm::searchZoomTo()
+{
+  QString filter = createFilterExpression();
+  if ( filter.isEmpty() )
+    return;
+
+  emit zoomToFeatures( filter );
+}
+
 void QgsAttributeForm::filterAndTriggered()
 {
   QString filter = createFilterExpression();
@@ -1310,6 +1319,12 @@ void QgsAttributeForm::init()
     boxLayout->addWidget( clearButton );
     boxLayout->addStretch( 1 );
 
+    QPushButton* zoomButton = new QPushButton();
+    zoomButton->setSizePolicy( QSizePolicy::Minimum, QSizePolicy::Minimum );
+    zoomButton->setText( tr( "&Zoom to features" ) );
+    connect( zoomButton, &QToolButton::clicked, this, &QgsAttributeForm::searchZoomTo );
+    boxLayout->addWidget( zoomButton );
+
     QToolButton* selectButton = new QToolButton();
     selectButton->setSizePolicy( QSizePolicy::Minimum, QSizePolicy::Minimum );
     selectButton->setText( tr( "&Select features" ) );

src/gui/qgsattributeform.h

@@ -191,6 +191,12 @@ class GUI_EXPORT QgsAttributeForm : public QWidget
      */
     void closed();
 
+    /**
+     * Emitted when the user chooses to zoom to a filtered set of features.
+     * @note added in QGIS 3.0
+     */
+    void zoomToFeatures( const QString& filter );
+
   public slots:
 
     /**
@@ -250,6 +256,7 @@ class GUI_EXPORT QgsAttributeForm : public QWidget
     void filterOrTriggered();
     void filterTriggered();
 
+    void searchZoomTo();
     void searchSetSelection();
     void searchAddToSelection();
     void searchRemoveFromSelection();

src/gui/qgsmapcanvas.h

@@ -288,6 +288,10 @@ class GUI_EXPORT QgsMapCanvas : public QGraphicsView
     //! Zooms in/out with a given center
     void zoomWithCenter( int x, int y, bool zoomIn );
 
+    //! Zooms to feature extent. Adds a small margin around the extent
+    //! and does a pan if rect is empty (point extent)
+    void zoomToFeatureExtent( QgsRectangle& rect );
+
     //! Returns whether the scale is locked, so zooming can be performed using magnication.
     //! @note added in 2.16
     //! @see setScaleLocked()
@@ -589,10 +593,6 @@ class GUI_EXPORT QgsMapCanvas : public QGraphicsView
     //! called when panning is in action, reset indicates end of panning
     void moveCanvasContents( bool reset = false );
 
-    //! Zooms to feature extent. Adds a small margin around the extent
-    //! and does a pan if rect is empty (point extent)
-    void zoomToFeatureExtent( QgsRectangle& rect );
-
     //! called on resize or changed extent to notify canvas items to change their rectangle
     void updateCanvasItemPositions();