Allow sorting attribute table by expression

images/images.qrc

@@ -583,6 +583,7 @@
         <file>themes/default/multieditMixedValues.svg</file>
         <file>themes/default/multieditSameValues.svg</file>
         <file>themes/default/locked_repeating.svg</file>
+        <file>themes/default/sort.svg</file>
     </qresource>
     <qresource prefix="/images/tips">
         <file alias="symbol_levels.png">qgis_tips/symbol_levels.png</file>

images/themes/default/sort.svg

@@ -0,0 +1,73 @@
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python/core/qgsattributetableconfig.sip

@@ -104,4 +104,15 @@ class QgsAttributeTableConfig
      * Deserialize to XML on layer load
      */
     void readXml( const QDomNode& node );
+
+    /**
+     * Get the expression used for sorting.
+     */
+    QString sortExpression() const;
+
+    /**
+     * Set the sort expression used for sorting.
+     */
+    void setSortExpression( const QString& sortExpression );
+
 };

python/gui/attributetable/qgsattributetablefiltermodel.sip

@@ -142,6 +142,20 @@ class QgsAttributeTableFilterModel: QSortFilterProxyModel, QgsFeatureModel
      */
     virtual void sort( int column, Qt::SortOrder order = Qt::AscendingOrder );
 
+    /**
+     * Sort by the given expression using the given order.
+     * Prefetches all the data from the layer to speed up sorting.
+     *
+     * @param column The expression which should be used for sorting
+     * @param order  The order ( Qt::AscendingOrder or Qt::DescendingOrder )
+     */
+    void sort( QString expression, Qt::SortOrder order = Qt::AscendingOrder );
+
+    /**
+     * The expression which is used to sort the attribute table.
+     */
+    QString sortExpression() const;
+
     /** Returns the map canvas*/
     QgsMapCanvas* mapCanvas() const;
 

python/gui/attributetable/qgsattributetablemodel.sip

@@ -148,6 +148,19 @@ class QgsAttributeTableModel : QAbstractTableModel
      */
     void prefetchColumnData( int column );
 
+    /**
+     * Prefetches the entire data for one expression. Based on this cached information
+     * the sorting can later be done in a performant way.
+     *
+     * @param expression The expression to cache
+     */
+    void prefetchSortData( const QString& expression );
+
+    /**
+     * The expression which was used to fill the sorting cache
+     */
+    QString sortCacheExpression() const;
+
     /**
      * Set a request that will be used to fill this attribute table model.
      * In contrast to a filter, the request will constrain the data shown without the possibility
@@ -160,7 +173,7 @@ class QgsAttributeTableModel : QAbstractTableModel
     /**
      * Get the the feature request
      */
-    const QgsFeatureRequest &request() const;
+    const QgsFeatureRequest& request() const;
 
     /**
      * Sets the context in which this table is shown.
@@ -188,7 +201,7 @@ class QgsAttributeTableModel : QAbstractTableModel
      * Empty extra columns to announce from this model.
      * Any extra columns need to be implemented by proxy models in front of this model.
      */
-    void setExtraColumns(int extraColumns);
+    void setExtraColumns( int extraColumns );
 
   public slots:
 
@@ -226,7 +239,7 @@ class QgsAttributeTableModel : QAbstractTableModel
      * Launched when eatures have been deleted
      * @param fids feature ids
      */
-    virtual void featuresDeleted( const QgsFeatureIds& fid );
+    virtual void featuresDeleted( const QgsFeatureIds& fids );
     /**
      * Launched when a feature has been added
      * @param fid feature id

python/gui/attributetable/qgsdualview.sip

@@ -115,10 +115,25 @@ class QgsDualView : QStackedWidget
      */
     QgsAttributeTableModel* masterModel() const;
 
+    /**
+     * Set the request
+     *
+     * @param request The request
+     */
     void setRequest( const QgsFeatureRequest& request );
 
+    /**
+     * Set the feature selection model
+     *
+     * @param featureSelectionManager the feature selection model
+     */
     void setFeatureSelectionManager( QgsIFeatureSelectionManager* featureSelectionManager );
 
+    /**
+     * Returns the table view
+     *
+     * @return The table view
+     */
     QgsAttributeTableView* tableView();
     /**
      * Set the attribute table config which should be used to control
@@ -126,6 +141,16 @@ class QgsDualView : QStackedWidget
      */
     void setAttributeTableConfig( const QgsAttributeTableConfig& config );
 
+    /**
+     * Set the expression used for sorting the table and feature list.
+     */
+    void setSortExpression( const QString& sortExpression );
+
+    /**
+     * Get the expression used for sorting the table and feature list.
+     */
+    QString sortExpression() const;
+
   protected:
     /**
      * Initializes widgets which depend on the attributes of this layer

src/app/qgsattributetabledialog.cpp

@@ -16,6 +16,8 @@
 
 #include <QDockWidget>
 #include <QMessageBox>
+#include <QGridLayout>
+#include <QDialogButtonBox>
 
 #include "qgsattributetabledialog.h"
 #include "qgsattributetablemodel.h"
@@ -23,11 +25,11 @@
 #include "qgsattributetableview.h"
 #include "qgsorganizetablecolumnsdialog.h"
 
-#include <qgsapplication.h>
-#include <qgsvectordataprovider.h>
-#include <qgsvectorlayer.h>
-#include <qgsexpression.h>
-
+#include "qgsapplication.h"
+#include "qgsvectorlayer.h"
+#include "qgsvectordataprovider.h"
+#include "qgsexpression.h"
+#include "qgsexpressionbuilderwidget.h"
 #include "qgisapp.h"
 #include "qgsaddattrdialog.h"
 #include "qgsdelattrdialog.h"
@@ -616,6 +618,52 @@ void QgsAttributeTableDialog::on_mAddFeature_clicked()
   }
 }
 
+void QgsAttributeTableDialog::on_mSortButton_clicked()
+{
+  QgsAttributeTableConfig config = mLayer->attributeTableConfig();
+
+  QDialog orderByDlg;
+  orderByDlg.setWindowTitle( tr( "Configure attribute table sort order" ) );
+  QDialogButtonBox* dialogButtonBox = new QDialogButtonBox( QDialogButtonBox::Ok | QDialogButtonBox::Cancel );
+  QGridLayout* layout = new QGridLayout();
+  connect( dialogButtonBox, SIGNAL( accepted() ), &orderByDlg, SLOT( accept() ) );
+  connect( dialogButtonBox, SIGNAL( rejected() ), &orderByDlg, SLOT( reject() ) );
+  orderByDlg.setLayout( layout );
+
+  QGroupBox* sortingGroupBox = new QGroupBox();
+  sortingGroupBox->setTitle( tr( "Enable sorting order in attribute table" ) );
+  sortingGroupBox->setCheckable( true );
+  sortingGroupBox->setChecked( !mMainView->sortExpression().isEmpty() );
+  layout->addWidget( sortingGroupBox );
+  sortingGroupBox->setLayout( new QGridLayout() );
+
+  QgsExpressionBuilderWidget* expressionBuilder = new QgsExpressionBuilderWidget();
+  expressionBuilder->setExpressionText( mMainView->sortExpression().isEmpty() ? mLayer->displayExpression() : mMainView->sortExpression() );
+  QgsExpressionContext context;
+  context << QgsExpressionContextUtils::globalScope()
+  << QgsExpressionContextUtils::projectScope();
+  expressionBuilder->setExpressionContext( context );
+  expressionBuilder->setLayer( mLayer );
+  sortingGroupBox->layout()->addWidget( expressionBuilder );
+
+  layout->addWidget( dialogButtonBox );
+  if ( orderByDlg.exec() )
+  {
+    if ( sortingGroupBox->isChecked() )
+    {
+      mMainView->setSortExpression( expressionBuilder->expressionText() );
+      config.setSortExpression( expressionBuilder->expressionText() );
+    }
+    else
+    {
+      mMainView->setSortExpression( QString() );
+      config.setSortExpression( QString() );
+    }
+
+    mLayer->setAttributeTableConfig( config );
+  }
+}
+
 void QgsAttributeTableDialog::on_mExpressionSelectButton_clicked()
 {
   QgsExpressionSelectionDialog* dlg = new QgsExpressionSelectionDialog( mLayer );

src/app/qgsattributetabledialog.h

@@ -154,6 +154,8 @@ class APP_EXPORT QgsAttributeTableDialog : public QDialog, private Ui::QgsAttrib
 
     void on_mHelpButton_clicked() { QgsContextHelp::run( metaObject()->className() ); }
 
+    void on_mSortButton_clicked();
+
     void on_mExpressionSelectButton_clicked();
     void filterColumnChanged( QObject* filterAction );
     void filterExpressionBuilder();

src/core/qgsattributetableconfig.cpp

@@ -173,6 +173,18 @@ void QgsAttributeTableConfig::readXml( const QDomNode& node )
       }
     }
   }
+
+  mSortExpression = configNode.toElement().attribute( "sortExpression" );
+}
+
+QString QgsAttributeTableConfig::sortExpression() const
+{
+  return mSortExpression;
+}
+
+void QgsAttributeTableConfig::setSortExpression( const QString& sortExpression )
+{
+  mSortExpression = sortExpression;
 }
 
 void QgsAttributeTableConfig::writeXml( QDomNode& node ) const
@@ -182,6 +194,8 @@ void QgsAttributeTableConfig::writeXml( QDomNode& node ) const
   QDomElement configElement  = doc.createElement( "attributetableconfig" );
   configElement.setAttribute( "actionWidgetStyle", mActionWidgetStyle == ButtonList ? "buttonList" : "dropDown" );
 
+  configElement.setAttribute( "sortExpression", mSortExpression );
+
   QDomElement columnsElement  = doc.createElement( "columns" );
 
   Q_FOREACH ( const ColumnConfig& column, mColumns )

src/core/qgsattributetableconfig.h

@@ -110,10 +110,20 @@ class CORE_EXPORT QgsAttributeTableConfig
      */
     void readXml( const QDomNode& node );
 
+    /**
+     * Get the expression used for sorting.
+     */
+    QString sortExpression() const;
+
+    /**
+     * Set the sort expression used for sorting.
+     */
+    void setSortExpression( const QString& sortExpression );
 
   private:
     QVector<ColumnConfig> mColumns;
     ActionWidgetStyle mActionWidgetStyle;
+    QString mSortExpression;
 };
 
 Q_DECLARE_METATYPE( QgsAttributeTableConfig::ColumnConfig )

src/gui/attributetable/qgsattributetablefiltermodel.cpp

@@ -194,6 +194,20 @@ void QgsAttributeTableFilterModel::setAttributeTableConfig( const QgsAttributeTa
       endResetModel();
     }
   }
+
+  sort( config.sortExpression() );
+}
+
+void QgsAttributeTableFilterModel::sort( QString expression, Qt::SortOrder order )
+{
+  QSortFilterProxyModel::sort( -1 );
+  masterModel()->prefetchSortData( expression );
+  QSortFilterProxyModel::sort( 0, order ) ;
+}
+
+QString QgsAttributeTableFilterModel::sortExpression() const
+{
+  return masterModel()->sortCacheExpression();
 }
 
 void QgsAttributeTableFilterModel::setSelectedOnTop( bool selectedOnTop )

src/gui/attributetable/qgsattributetablefiltermodel.h

@@ -178,6 +178,20 @@ class GUI_EXPORT QgsAttributeTableFilterModel: public QSortFilterProxyModel, pub
      */
     virtual void sort( int column, Qt::SortOrder order = Qt::AscendingOrder ) override;
 
+    /**
+     * Sort by the given expression using the given order.
+     * Prefetches all the data from the layer to speed up sorting.
+     *
+     * @param expression The expression which should be used for sorting
+     * @param order      The order ( Qt::AscendingOrder or Qt::DescendingOrder )
+     */
+    void sort( QString expression, Qt::SortOrder order = Qt::AscendingOrder );
+
+    /**
+     * The expression which is used to sort the attribute table.
+     */
+    QString sortExpression() const;
+
     /** Returns the map canvas*/
     QgsMapCanvas* mapCanvas() const { return mCanvas; }
 

src/gui/attributetable/qgsattributetablemodel.cpp

@@ -39,7 +39,7 @@ QgsAttributeTableModel::QgsAttributeTableModel( QgsVectorLayerCache *layerCache,
     : QAbstractTableModel( parent )
     , mLayerCache( layerCache )
     , mFieldCount( 0 )
-    , mCachedField( -1 )
+    , mSortCacheExpression( "" )
     , mExtraColumns( 0 )
 {
   mExpressionContext << QgsExpressionContextUtils::globalScope()
@@ -160,7 +160,7 @@ bool QgsAttributeTableModel::removeRows( int row, int count, const QModelIndex &
   // clean old references
   for ( int i = row; i < row + count; i++ )
   {
-    mFieldCache.remove( mRowIdMap[i] );
+    mSortCache.remove( mRowIdMap[i] );
     mIdRowMap.remove( mRowIdMap[i] );
     mRowIdMap.remove( i );
   }
@@ -206,7 +206,8 @@ void QgsAttributeTableModel::featureAdded( QgsFeatureId fid )
 
   if ( featOk && mFeatureRequest.acceptFeature( mFeat ) )
   {
-    mFieldCache[fid] = mFeat.attribute( mCachedField );
+    mExpressionContext.setFeature( mFeat );
+    mSortCache[fid] = mSortCacheExpression.evaluate();
 
     int n = mRowIdMap.size();
     beginInsertRows( QModelIndex(), n, n );
@@ -236,10 +237,8 @@ void QgsAttributeTableModel::editCommandEnded()
 
 void QgsAttributeTableModel::attributeDeleted( int idx )
 {
-  if ( idx == mCachedField )
-  {
-    prefetchColumnData( -1 );
-  }
+  if ( mSortCacheAttributes.contains( idx ) )
+    prefetchSortData( "" );
 }
 
 void QgsAttributeTableModel::layerDeleted()
@@ -256,9 +255,13 @@ void QgsAttributeTableModel::attributeValueChanged( QgsFeatureId fid, int idx, c
 {
   QgsDebugMsgLevel( QString( "(%4) fid: %1, idx: %2, value: %3" ).arg( fid ).arg( idx ).arg( value.toString() ).arg( mFeatureRequest.filterType() ), 3 );
 
-  if ( idx == mCachedField )
-    mFieldCache[fid] = value;
-
+  if ( mSortCacheAttributes.contains( idx ) )
+  {
+    // if the expression used multiple fields, this will not work but this way we don't have
+    // to run the expensive query in the 80% cases where we just have a simple column for sorting
+    // or it's the first used column, this works just fine
+    mSortCache[fid] = value;
+  }
   // No filter request: skip all possibly heavy checks
   if ( mFeatureRequest.filterType() == QgsFeatureRequest::FilterNone )
   {
@@ -577,27 +580,22 @@ QVariant QgsAttributeTableModel::data( const QModelIndex &index, int role ) cons
       return QVariant( Qt::AlignLeft );
   }
 
-  QVariant val;
-
-  // if we don't have the row in current cache, load it from layer first
-  if ( mCachedField == fieldId )
+  if ( role == SortRole )
   {
-    val = mFieldCache[rowId];
+    return mSortCache[rowId];
   }
-  else
+
+  if ( mFeat.id() != rowId || !mFeat.isValid() )
   {
-    if ( mFeat.id() != rowId || !mFeat.isValid() )
-    {
-      if ( !loadFeatureAtId( rowId ) )
-        return QVariant( "ERROR" );
+    if ( !loadFeatureAtId( rowId ) )
+      return QVariant( "ERROR" );
 
-      if ( mFeat.id() != rowId )
-        return QVariant( "ERROR" );
-    }
-
-    val = mFeat.attribute( fieldId );
+    if ( mFeat.id() != rowId )
+      return QVariant( "ERROR" );
   }
 
+  QVariant val = mFeat.attribute( fieldId );
+
   if ( role == Qt::DisplayRole )
   {
     return mWidgetFactories[index.column()]->representValue( layer(), fieldId, mWidgetConfigs[index.column()], mAttributeWidgetCaches[index.column()], val );
@@ -730,34 +728,51 @@ QgsFeature QgsAttributeTableModel::feature( const QModelIndex &idx ) const
 
 void QgsAttributeTableModel::prefetchColumnData( int column )
 {
-  mFieldCache.clear();
-
-  if ( column == -1 )
+  if ( column == -1 || column >= mAttributes.count() )
   {
-    mCachedField = -1;
+    prefetchSortData( "" );
   }
   else
   {
-    if ( column >= mAttributes.count() )
-      return;
-    int fieldId = mAttributes.at( column );
-    const QgsFields& fields = layer()->fields();
-    QStringList fldNames;
-    fldNames << fields[fieldId].name();
-
-    QgsFeatureRequest r( mFeatureRequest );
-    QgsFeatureIterator it = mLayerCache->getFeatures( r.setFlags( QgsFeatureRequest::NoGeometry ).setSubsetOfAttributes( fldNames, fields ) );
-
-    QgsFeature f;
-    while ( it.nextFeature( f ) )
-    {
-      mFieldCache.insert( f.id(), f.attribute( fieldId ) );
-    }
-
-    mCachedField = fieldId;
+    prefetchSortData( mLayerCache->layer()->fields().at( mAttributes.at( column ) ).name() );
   }
 }
 
+void QgsAttributeTableModel::prefetchSortData( const QString& expressionString )
+{
+  mSortCache.clear();
+  mSortCacheAttributes.clear();
+
+  mSortCacheExpression = QgsExpression( expressionString );
+
+  mSortCacheExpression.prepare( &mExpressionContext );
+
+  Q_FOREACH ( const QString& col, mSortCacheExpression.referencedColumns() )
+  {
+    mSortCacheAttributes.append( mLayerCache->layer()->fieldNameIndex( col ) );
+  }
+
+  QgsFeatureRequest request = QgsFeatureRequest( mFeatureRequest )
+                              .setFlags( QgsFeatureRequest::NoGeometry )
+                              .setSubsetOfAttributes( mSortCacheAttributes );
+  QgsFeatureIterator it = mLayerCache->getFeatures( request );
+
+  QgsFeature f;
+  while ( it.nextFeature( f ) )
+  {
+    mExpressionContext.setFeature( f );
+    mSortCache.insert( f.id(), mSortCacheExpression.evaluate( &mExpressionContext ) );
+  }
+}
+
+QString QgsAttributeTableModel::sortCacheExpression() const
+{
+  if ( mSortCacheExpression.rootNode() )
+    return mSortCacheExpression.expression();
+  else
+    return QString();
+}
+
 void QgsAttributeTableModel::setRequest( const QgsFeatureRequest& request )
 {
   mFeatureRequest = request;

src/gui/attributetable/qgsattributetablemodel.h

@@ -193,6 +193,19 @@ class GUI_EXPORT QgsAttributeTableModel: public QAbstractTableModel
      */
     void prefetchColumnData( int column );
 
+    /**
+     * Prefetches the entire data for one expression. Based on this cached information
+     * the sorting can later be done in a performant way.
+     *
+     * @param expression The expression to cache
+     */
+    void prefetchSortData( const QString& expression );
+
+    /**
+     * The expression which was used to fill the sorting cache
+     */
+    QString sortCacheExpression() const;
+
     /**
      * Set a request that will be used to fill this attribute table model.
      * In contrast to a filter, the request will constrain the data shown without the possibility
@@ -335,9 +348,10 @@ class GUI_EXPORT QgsAttributeTableModel: public QAbstractTableModel
     QgsFeatureRequest mFeatureRequest;
 
     /** The currently cached column */
-    int mCachedField;
-    /** Allows caching of one specific column (used for sorting) */
-    QHash<QgsFeatureId, QVariant> mFieldCache;
+    QgsExpression mSortCacheExpression;
+    QgsAttributeList mSortCacheAttributes;
+    /** Allows caching of one value per column (used for sorting) */
+    QHash<QgsFeatureId, QVariant> mSortCache;
 
     /**
      * Holds the bounds of changed cells while an update operation is running

src/gui/attributetable/qgsdualview.cpp

@@ -196,6 +196,10 @@ void QgsDualView::columnBoxInit()
   {
     mFeatureListPreviewButton->defaultAction()->trigger();
   }
+
+  QAction* sortByPreviewExpression = new QAction( QgsApplication::getThemeIcon( "sort.svg" ), tr( "Sort by preview expression" ), this );
+  connect( sortByPreviewExpression, SIGNAL( triggered( bool ) ), this, SLOT( sortByPreviewExpression() ) );
+  mFeatureListPreviewButton->addAction( sortByPreviewExpression );
 }
 
 void QgsDualView::setView( QgsDualView::ViewMode view )
@@ -439,6 +443,11 @@ void QgsDualView::previewExpressionChanged( const QString& expression )
   mLayerCache->layer()->setDisplayExpression( expression );
 }
 
+void QgsDualView::sortByPreviewExpression()
+{
+  setSortExpression( mFeatureList->displayExpression() );
+}
+
 void QgsDualView::featureFormAttributeChanged()
 {
   mFeatureList->setCurrentFeatureEdited( true );
@@ -470,6 +479,19 @@ void QgsDualView::setAttributeTableConfig( const QgsAttributeTableConfig& config
   mFilterModel->setAttributeTableConfig( config );
 }
 
+void QgsDualView::setSortExpression( const QString& sortExpression )
+{
+  if ( sortExpression.isNull() )
+    mFilterModel->sort( -1 );
+  else
+    mFilterModel->sort( sortExpression );
+}
+
+QString QgsDualView::sortExpression() const
+{
+  return mFilterModel->sortExpression();
+}
+
 void QgsDualView::progress( int i, bool& cancel )
 {
   if ( !mProgressDlg )

src/gui/attributetable/qgsdualview.h

@@ -180,6 +180,16 @@ class GUI_EXPORT QgsDualView : public QStackedWidget, private Ui::QgsDualViewBas
      */
     void setAttributeTableConfig( const QgsAttributeTableConfig& config );
 
+    /**
+     * Set the expression used for sorting the table and feature list.
+     */
+    void setSortExpression( const QString& sortExpression );
+
+    /**
+     * Get the expression used for sorting the table and feature list.
+     */
+    QString sortExpression() const;
+
   protected:
     /**
      * Initializes widgets which depend on the attributes of this layer
@@ -240,6 +250,8 @@ class GUI_EXPORT QgsDualView : public QStackedWidget, private Ui::QgsDualViewBas
 
     void previewExpressionChanged( const QString& expression );
 
+    void sortByPreviewExpression();
+
     /**
      * Will be called whenever the currently shown feature form changes.
      * Will forward this signal to the feature list to visually represent

src/ui/qgsattributetabledialog.ui

@@ -14,7 +14,16 @@
    <string>Attribute Table</string>
   </property>
   <layout class="QGridLayout" name="gridLayout">
-   <property name="margin">
+   <property name="leftMargin">
+    <number>0</number>
+   </property>
+   <property name="topMargin">
+    <number>0</number>
+   </property>
+   <property name="rightMargin">
+    <number>0</number>
+   </property>
+   <property name="bottomMargin">
     <number>0</number>
    </property>
    <property name="spacing">
@@ -566,6 +575,29 @@
        </property>
       </widget>
      </item>
+     <item>
+      <widget class="QToolButton" name="mSortButton">
+       <property name="toolTip">
+        <string>Control the sort order</string>
+       </property>
+       <property name="text">
+        <string>...</string>
+       </property>
+       <property name="icon">
+        <iconset resource="../../images/images.qrc">
+         <normaloff>:/images/themes/default/sort.svg</normaloff>:/images/themes/default/sort.svg</iconset>
+       </property>
+       <property name="iconSize">
+        <size>
+         <width>18</width>
+         <height>18</height>
+        </size>
+       </property>
+       <property name="autoRaise">
+        <bool>true</bool>
+       </property>
+      </widget>
+     </item>
      <item>
       <spacer name="horizontalSpacer">
        <property name="orientation">
@@ -670,7 +702,16 @@
         <property name="sizeConstraint">
          <enum>QLayout::SetDefaultConstraint</enum>
         </property>
-        <property name="margin">
+        <property name="leftMargin">
+         <number>0</number>
+        </property>
+        <property name="topMargin">
+         <number>0</number>
+        </property>
+        <property name="rightMargin">
+         <number>0</number>
+        </property>
+        <property name="bottomMargin">
          <number>0</number>
         </property>
         <item row="0" column="0">