[FEATURE] Show stats for string and date fields in stats dock

src/app/qgsstatisticalsummarydockwidget.cpp

@@ -38,6 +38,23 @@ QList< QgsStatisticalSummary::Statistic > QgsStatisticalSummaryDockWidget::mDisp
   << QgsStatisticalSummary::ThirdQuartile
   << QgsStatisticalSummary::InterQuartileRange;
 
+QList< QgsStringStatisticalSummary::Statistic > QgsStatisticalSummaryDockWidget::mDisplayStringStats =
+  QList< QgsStringStatisticalSummary::Statistic > () << QgsStringStatisticalSummary::Count
+  << QgsStringStatisticalSummary::CountDistinct
+  << QgsStringStatisticalSummary::CountMissing
+  << QgsStringStatisticalSummary::Min
+  << QgsStringStatisticalSummary::Max
+  << QgsStringStatisticalSummary::MinimumLength
+  << QgsStringStatisticalSummary::MaximumLength;
+
+QList< QgsDateTimeStatisticalSummary::Statistic > QgsStatisticalSummaryDockWidget::mDisplayDateTimeStats =
+  QList< QgsDateTimeStatisticalSummary::Statistic > () << QgsDateTimeStatisticalSummary::Count
+  << QgsDateTimeStatisticalSummary::CountDistinct
+  << QgsDateTimeStatisticalSummary::CountMissing
+  << QgsDateTimeStatisticalSummary::Min
+  << QgsDateTimeStatisticalSummary::Max
+  << QgsDateTimeStatisticalSummary::Range;
+
 #define MISSING_VALUES -1
 
 static QgsExpressionContext _getExpressionContext( const void* context )
@@ -65,7 +82,9 @@ QgsStatisticalSummaryDockWidget::QgsStatisticalSummaryDockWidget( QWidget *paren
   mFieldExpressionWidget->registerGetExpressionContextCallback( &_getExpressionContext, this );
 
   mLayerComboBox->setFilters( QgsMapLayerProxyModel::VectorLayer );
-  mFieldExpressionWidget->setFilters( QgsFieldProxyModel::Numeric );
+  mFieldExpressionWidget->setFilters( QgsFieldProxyModel::Numeric |
+                                      QgsFieldProxyModel::String |
+                                      QgsFieldProxyModel::Date );
 
   mLayerComboBox->setLayer( mLayerComboBox->layer( 0 ) );
   mFieldExpressionWidget->setLayer( mLayerComboBox->layer( 0 ) );
@@ -113,10 +132,47 @@ void QgsStatisticalSummaryDockWidget::refreshStatistics()
     return;
   }
 
+  // non numeric field?
+  bool isNumeric = true;
+  QVariant::Type fieldType = QVariant::Double;
+  if ( !mFieldExpressionWidget->isExpression() )
+  {
+    QString field = mFieldExpressionWidget->currentField();
+    fieldType = mLayer->fields().field( mLayer->fields().fieldNameIndex( field ) ).type();
+    if ( fieldType == QVariant::String || fieldType == QVariant::Date || fieldType == QVariant::DateTime )
+    {
+      isNumeric = false;
+    }
+  }
+
+  bool selectedOnly = mSelectedOnlyCheckBox->isChecked();
+
+  if ( isNumeric )
+  {
+    updateNumericStatistics( selectedOnly );
+  }
+  else
+  {
+    switch ( fieldType )
+    {
+      case QVariant::String:
+        updateStringStatistics( selectedOnly );
+        break;
+      case QVariant::Date:
+      case QVariant::DateTime:
+        updateDateTimeStatistics( selectedOnly );
+        break;
+      default:
+        break;
+    }
+  }
+}
+
+void QgsStatisticalSummaryDockWidget::updateNumericStatistics( bool selectedOnly )
+{
   QString sourceFieldExp = mFieldExpressionWidget->currentField();
 
   bool ok;
-  bool selectedOnly = mSelectedOnlyCheckBox->isChecked();
   int missingValues = 0;
   QList< double > values = mLayer->getDoubleValues( sourceFieldExp, ok, selectedOnly, &missingValues );
 
@@ -150,38 +206,46 @@ void QgsStatisticalSummaryDockWidget::refreshStatistics()
   int row = 0;
   Q_FOREACH ( QgsStatisticalSummary::Statistic stat, statsToDisplay )
   {
-    QTableWidgetItem* nameItem = new QTableWidgetItem( QgsStatisticalSummary::displayName( stat ) );
-    nameItem->setToolTip( nameItem->text() );
-    nameItem->setFlags( Qt::ItemIsSelectable | Qt::ItemIsEnabled );
-    mStatisticsTable->setItem( row, 0, nameItem );
-
-    QTableWidgetItem* valueItem = new QTableWidgetItem();
-    if ( stats.count() != 0 )
-    {
-      valueItem->setText( QString::number( stats.statistic( stat ) ) );
-    }
-    valueItem->setToolTip( valueItem->text() );
-    valueItem->setFlags( Qt::ItemIsSelectable | Qt::ItemIsEnabled );
-    mStatisticsTable->setItem( row, 1, valueItem );
-
+    addRow( row, QgsStatisticalSummary::displayName( stat ),
+            QString::number( stats.statistic( stat ) ),
+            stats.count() != 0 );
     row++;
   }
 
   if ( mStatsActions.value( MISSING_VALUES )->isChecked() )
   {
-    QTableWidgetItem* nameItem = new QTableWidgetItem( tr( "Missing (null) values" ) );
-    nameItem->setToolTip( nameItem->text() );
-    nameItem->setFlags( Qt::ItemIsSelectable | Qt::ItemIsEnabled );
-    mStatisticsTable->setItem( row, 0, nameItem );
+    addRow( row, tr( "Missing (null) values" ),
+            QString::number( missingValues ),
+            stats.count() != 0 || missingValues != 0 );
+    row++;
+  }
+}
 
-    QTableWidgetItem* valueItem = new QTableWidgetItem();
-    if ( stats.count() != 0 || missingValues != 0 )
-    {
-      valueItem->setText( QString::number( missingValues ) );
-    }
-    valueItem->setToolTip( valueItem->text() );
-    valueItem->setFlags( Qt::ItemIsSelectable | Qt::ItemIsEnabled );
-    mStatisticsTable->setItem( row, 1, valueItem );
+void QgsStatisticalSummaryDockWidget::updateStringStatistics( bool selectedOnly )
+{
+  QString field = mFieldExpressionWidget->currentField();
+
+  bool ok;
+  QVariantList values = mLayer->getValues( field, ok, selectedOnly );
+
+  if ( ! ok )
+  {
+    return;
+  }
+
+  QgsStringStatisticalSummary stats;
+  stats.setStatistics( QgsStringStatisticalSummary::All );
+  stats.calculateFromVariants( values );
+
+  mStatisticsTable->setRowCount( mDisplayStringStats.count() );
+  mStatisticsTable->setColumnCount( 2 );
+
+  int row = 0;
+  Q_FOREACH ( QgsStringStatisticalSummary::Statistic stat, mDisplayStringStats )
+  {
+    addRow( row, QgsStringStatisticalSummary::displayName( stat ),
+            stats.statistic( stat ).toString(),
+            stats.count() != 0 );
     row++;
   }
 }
@@ -244,3 +308,55 @@ void QgsStatisticalSummaryDockWidget::layerSelectionChanged()
   if ( mSelectedOnlyCheckBox->isChecked() )
     refreshStatistics();
 }
+
+void QgsStatisticalSummaryDockWidget::updateDateTimeStatistics( bool selectedOnly )
+{
+  QString field = mFieldExpressionWidget->currentField();
+
+  bool ok;
+  QVariantList values = mLayer->getValues( field, ok, selectedOnly );
+
+  if ( ! ok )
+  {
+    return;
+  }
+
+  QgsDateTimeStatisticalSummary stats;
+  stats.setStatistics( QgsDateTimeStatisticalSummary::All );
+  stats.calculate( values );
+
+  mStatisticsTable->setRowCount( mDisplayDateTimeStats.count() );
+  mStatisticsTable->setColumnCount( 2 );
+
+  int row = 0;
+  Q_FOREACH ( QgsDateTimeStatisticalSummary::Statistic stat, mDisplayDateTimeStats )
+  {
+    QString value = ( stat == QgsDateTimeStatisticalSummary::Range
+                      ? tr( "%1 seconds" ).arg( stats.range().seconds() )
+                      : stats.statistic( stat ).toString() );
+
+    addRow( row, QgsDateTimeStatisticalSummary::displayName( stat ),
+            value,
+            stats.count() != 0 );
+    row++;
+  }
+}
+
+void QgsStatisticalSummaryDockWidget::addRow( int row, const QString& name, const QString& value,
+    bool showValue )
+{
+  QTableWidgetItem* nameItem = new QTableWidgetItem( name );
+  nameItem->setToolTip( name );
+  nameItem->setFlags( Qt::ItemIsSelectable | Qt::ItemIsEnabled );
+  mStatisticsTable->setItem( row, 0, nameItem );
+
+  QTableWidgetItem* valueItem = new QTableWidgetItem();
+  if ( showValue )
+  {
+    valueItem->setText( value );
+  }
+  valueItem->setToolTip( value );
+  valueItem->setFlags( Qt::ItemIsSelectable | Qt::ItemIsEnabled );
+  mStatisticsTable->setItem( row, 1, valueItem );
+}
+

src/app/qgsstatisticalsummarydockwidget.h

@@ -20,6 +20,8 @@
 #include "ui_qgsstatisticalsummarybase.h"
 
 #include "qgsstatisticalsummary.h"
+#include "qgsstringstatisticalsummary.h"
+#include "qgsdatetimestatisticalsummary.h"
 
 class QgsBrowserModel;
 class QModelIndex;
@@ -62,6 +64,13 @@ class APP_EXPORT QgsStatisticalSummaryDockWidget : public QDockWidget, private U
 
     QMap< int, QAction* > mStatsActions;
     static QList< QgsStatisticalSummary::Statistic > mDisplayStats;
+    static QList< QgsStringStatisticalSummary::Statistic > mDisplayStringStats;
+    static QList< QgsDateTimeStatisticalSummary::Statistic > mDisplayDateTimeStats;
+
+    void updateNumericStatistics( bool selectedOnly );
+    void updateStringStatistics( bool selectedOnly );
+    void updateDateTimeStatistics( bool selectedOnly );
+    void addRow( int row, const QString& name, const QString& value, bool showValue );
 };
 
 #endif // QGSSTATISTICALSUMMARYDOCKWIDGET_H