field proxy model to filter fields on their type (also fix #10181)

Author: 3nids

python/gui/gui.sip

@@ -32,6 +32,7 @@
 %Include qgsfieldexpressionwidget.sip
 %Include qgsfieldmodel.sip
 %Include qgsfieldvalidator.sip
+%Include qgsfieldproxymodel.sip
 %Include qgsfiledropedit.sip
 %Include qgsfilterlineedit.sip
 %Include qgsformannotationitem.sip

python/gui/qgsfieldcombobox.sip

@@ -19,6 +19,12 @@ class QgsFieldComboBox : QComboBox
      */
     explicit QgsFieldComboBox( QWidget *parent /TransferThis/ = 0 );
 
+    //! setFilters allows fitering according to the type of field
+    void setFilters( QgsFieldProxyModel::Filters filters );
+
+    //! currently used filter on list of fields
+    QgsFieldProxyModel::Filters filters();
+
     //! return the currently selected field
     QString currentField();
 

python/gui/qgsfieldexpressionwidget.sip

@@ -13,13 +13,19 @@ class QgsFieldExpressionWidget : QWidget
 
     //! define the title used in the expression dialog
     void setExpressionDialogTitle( QString title );
+    
+    //! setFilters allows fitering according to the type of field
+    void setFilters( QgsFieldProxyModel::Filters filters );
 
-    //! set the geometry calculator used in the expression dialog
-    void setGeomCalculator( const QgsDistanceArea &da );
+    //! currently used filter on list of fields
+    QgsFieldProxyModel::Filters filters();
 
     //! return the title used for the expression dialog
     const QString expressionDialogTitle();
 
+    //! set the geometry calculator used in the expression dialog
+    void setGeomCalculator( const QgsDistanceArea &da );
+    
     /**
      * @brief currentField returns the currently selected field or expression if allowed
      * @param isExpression determines if the string returned is the name of a field or an expression

python/gui/qgsfieldmodel.sip

@@ -18,7 +18,8 @@ class QgsFieldModel : QAbstractItemModel
       FieldIndexRole = 34, /* return field index if index corresponds to a field */
       ExpressionRole = 35, /* return field name or expression */
       IsExpressionRole = 36, /* return if index corresponds to an expression */
-      ExpressionValidityRole = 37 /* return if expression is valid or not */
+      ExpressionValidityRole = 37, /* return if expression is valid or not */
+      FieldTypeRole = 38 /* return the field type (if a field, return QVariant if expression) */
     };
 
     /**

python/gui/qgsfieldproxymodel.sip

@@ -0,0 +1,47 @@
+/**
+ * @brief The QgsMapLayerProxModel class provides an easy to use model to display the list of layers in widgets.
+ * @note added in 2.3
+ */
+class QgsFieldProxyModel : QSortFilterProxyModel
+{
+
+%TypeHeaderCode
+#include "qgsfieldproxymodel.h"
+%End
+
+  public:
+    enum Filter
+    {
+      String = 1,
+      Int = 2,
+      LongLong = 4,
+      Double = 8,
+      Numeric = 14,
+      Date = 16,
+      All = 31
+    };
+    typedef QFlags<QgsFieldProxyModel::Filter> Filters;
+
+    /**
+     * @brief QgsFieldProxModel creates a proxy model with a QgsFieldModel as source model.
+     * It can be used to filter the fields based on their types.
+     */
+    explicit QgsFieldProxyModel( QObject *parent /TransferThis/ = 0 );
+
+    //! sourceFieldModel returns the QgsFieldModel used in this QSortFilterProxyModel
+    QgsFieldModel* sourceFieldModel() ;
+
+    /**
+     * @brief setFilters set flags that affect how fields are filtered
+     * @param filters are Filter flags
+     * @note added in 2.3
+     */
+    QgsFieldProxyModel* setFilters( Filters filters );
+    const Filters& filters() const ;
+
+    // QSortFilterProxyModel interface
+  public:
+    bool filterAcceptsRow( int source_row, const QModelIndex &source_parent ) const;
+    bool lessThan( const QModelIndex &left, const QModelIndex &right ) const;
+};
+

src/gui/CMakeLists.txt

@@ -92,6 +92,7 @@ qgsfieldcombobox.cpp
 qgsfieldexpressionwidget.cpp
 qgsfieldmodel.cpp
 qgsfieldvalidator.cpp
+qgsfieldproxymodel.cpp
 qgsfiledropedit.cpp
 qgsfilterlineedit.cpp
 qgsformannotationitem.cpp
@@ -238,6 +239,7 @@ qgsfieldcombobox.h
 qgsfieldexpressionwidget.h
 qgsfieldmodel.h
 qgsfieldvalidator.h
+qgsfieldproxymodel.h
 qgsfilterlineedit.h
 qgsformannotationitem.h
 qgsgenericprojectionselector.h
@@ -310,6 +312,7 @@ qgsfieldcombobox.h
 qgsfieldexpressionwidget.h
 qgsfieldmodel.h
 qgsfieldvalidator.h
+qgsfieldproxymodel.h
 qgsfiledropedit.h
 qgsfilterlineedit.h
 qgsgenericprojectionselector.h

src/gui/qgsfieldcombobox.cpp

@@ -14,18 +14,24 @@
 ***************************************************************************/
 
 #include "qgsfieldcombobox.h"
-#include "qgsfieldmodel.h"
+#include "qgsfieldproxymodel.h"
 #include "qgsmaplayer.h"
+#include "qgsvectorlayer.h"
 
 QgsFieldComboBox::QgsFieldComboBox( QWidget *parent ) :
     QComboBox( parent )
 {
-  mFieldModel = new QgsFieldModel( this );
-  setModel( mFieldModel );
+  mFieldProxyModel = new QgsFieldProxyModel( this );
+  setModel( mFieldProxyModel );
 
   connect( this, SIGNAL( currentIndexChanged( int ) ), this, SLOT( indexChanged( int ) ) );
 }
 
+void QgsFieldComboBox::setFilters( QgsFieldProxyModel::Filters filters )
+{
+  mFieldProxyModel->setFilters( filters );
+}
+
 void QgsFieldComboBox::setLayer( QgsMapLayer *layer )
 {
   QgsVectorLayer* vl = dynamic_cast<QgsVectorLayer*>( layer );
@@ -37,38 +43,46 @@ void QgsFieldComboBox::setLayer( QgsMapLayer *layer )
 
 void QgsFieldComboBox::setLayer( QgsVectorLayer *layer )
 {
-  mFieldModel->setLayer( layer );
+  mFieldProxyModel->sourceFieldModel()->setLayer( layer );
 }
 
 QgsVectorLayer *QgsFieldComboBox::layer()
 {
-  return mFieldModel->layer();
+  return mFieldProxyModel->sourceFieldModel()->layer();
 }
 
 void QgsFieldComboBox::setField( QString fieldName )
 {
-  QModelIndex idx = mFieldModel->indexFromName( fieldName );
+  QModelIndex idx = mFieldProxyModel->sourceFieldModel()->indexFromName( fieldName );
   if ( idx.isValid() )
   {
-    setCurrentIndex( idx.row() );
-  }
-  else
-  {
-    setCurrentIndex( -1 );
+    QModelIndex proxyIdx = mFieldProxyModel->mapFromSource( idx );
+    if ( proxyIdx.isValid() )
+    {
+      setCurrentIndex( idx.row() );
+      return;
+    }
   }
+  setCurrentIndex( -1 );
 }
 
 QString QgsFieldComboBox::currentField()
 {
   int i = currentIndex();
 
-  const QModelIndex index = mFieldModel->index( i, 0 );
+  const QModelIndex proxyIndex = mFieldProxyModel->index( i, 0 );
+  if ( !proxyIndex.isValid() )
+  {
+    return "";
+  }
+
+  const QModelIndex index = mFieldProxyModel->mapToSource( proxyIndex );
   if ( !index.isValid() )
   {
     return "";
   }
 
-  QString name = mFieldModel->data( index, QgsFieldModel::FieldNameRole ).toString();
+  QString name = mFieldProxyModel->data( index, QgsFieldModel::FieldNameRole ).toString();
   return name;
 }
 

src/gui/qgsfieldcombobox.h

@@ -18,7 +18,8 @@
 
 #include <QComboBox>
 
-class QgsFieldModel;
+#include "qgsfieldproxymodel.h"
+
 class QgsMapLayer;
 class QgsVectorLayer;
 
@@ -32,13 +33,21 @@ class QgsVectorLayer;
 class GUI_EXPORT QgsFieldComboBox : public QComboBox
 {
     Q_OBJECT
+    Q_PROPERTY( QgsFieldProxyModel::Filters filters READ filters WRITE setFilters )
+
   public:
     /**
      * @brief QgsFieldComboBox creates a combo box to display the fields of a layer.
      * The layer can be either manually given or dynamically set by connecting the signal QgsMapLayerComboBox::layerChanged to the slot setLayer.
      */
     explicit QgsFieldComboBox( QWidget *parent = 0 );
 
+    //! setFilters allows fitering according to the type of field
+    void setFilters( QgsFieldProxyModel::Filters filters );
+
+    //! currently used filter on list of fields
+    QgsFieldProxyModel::Filters filters() { return mFieldProxyModel->filters(); }
+
     //! return the currently selected field
     QString currentField();
 
@@ -63,7 +72,7 @@ class GUI_EXPORT QgsFieldComboBox : public QComboBox
     void indexChanged( int i );
 
   private:
-    QgsFieldModel* mFieldModel;
+    QgsFieldProxyModel* mFieldProxyModel;
 };
 
 #endif // QGSFIELDCOMBOBOX_H

src/gui/qgsfieldexpressionwidget.cpp

@@ -19,7 +19,7 @@
 #include "qgsapplication.h"
 #include "qgsfieldexpressionwidget.h"
 #include "qgsexpressionbuilderdialog.h"
-#include "qgsfieldmodel.h"
+#include "qgsfieldproxymodel.h"
 #include "qgsdistancearea.h"
 
 QgsFieldExpressionWidget::QgsFieldExpressionWidget( QWidget *parent )
@@ -32,9 +32,9 @@ QgsFieldExpressionWidget::QgsFieldExpressionWidget( QWidget *parent )
   mCombo = new QComboBox( this );
   mCombo->setEditable( true );
   mCombo->setSizePolicy( QSizePolicy::MinimumExpanding, QSizePolicy::Minimum );
-  mFieldModel = new QgsFieldModel( mCombo );
-  mFieldModel->setAllowExpression( true );
-  mCombo->setModel( mFieldModel );
+  mFieldProxyModel = new QgsFieldProxyModel( mCombo );
+  mFieldProxyModel->sourceFieldModel()->setAllowExpression( true );
+  mCombo->setModel( mFieldProxyModel );
 
   mButton = new QToolButton( this );
   mButton->setSizePolicy( QSizePolicy::Minimum, QSizePolicy::Minimum );
@@ -59,6 +59,11 @@ void QgsFieldExpressionWidget::setExpressionDialogTitle( QString title )
   mExpressionDialogTitle = title;
 }
 
+void QgsFieldExpressionWidget::setFilters( QgsFieldProxyModel::Filters filters )
+{
+  mFieldProxyModel->setFilters( filters );
+}
+
 void QgsFieldExpressionWidget::setGeomCalculator( const QgsDistanceArea &da )
 {
   mDa = QSharedPointer<const QgsDistanceArea>( new QgsDistanceArea( da ) );
@@ -76,27 +81,28 @@ QString QgsFieldExpressionWidget::currentField( bool *isExpression , bool *isVal
   }
 
   int i = mCombo->currentIndex();
-  const QModelIndex index = mFieldModel->index( i, 0 );
+  const QModelIndex proxyIndex = mFieldProxyModel->index( i, 0 );
+  if ( !proxyIndex.isValid() )
+    return "";
+  const QModelIndex index = mFieldProxyModel->mapToSource( proxyIndex );
   if ( !index.isValid() )
-  {
     return "";
-  }
 
   if ( isExpression )
   {
-    *isExpression = mFieldModel->data( index, QgsFieldModel::IsExpressionRole ).toBool();
+    *isExpression = mFieldProxyModel->data( index, QgsFieldModel::IsExpressionRole ).toBool();
   }
   if ( isValid )
   {
-    *isValid = mFieldModel->data( index, QgsFieldModel::ExpressionValidityRole ).toBool();
+    *isValid = mFieldProxyModel->data( index, QgsFieldModel::ExpressionValidityRole ).toBool();
   }
-  QString expression = mFieldModel->data( index, QgsFieldModel::ExpressionRole ).toString();
+  QString expression = mFieldProxyModel->data( index, QgsFieldModel::ExpressionRole ).toString();
   return expression;
 }
 
 QgsVectorLayer *QgsFieldExpressionWidget::layer()
 {
-  return mFieldModel->layer();
+  return mFieldProxyModel->sourceFieldModel()->layer();
 }
 
 void QgsFieldExpressionWidget::setLayer( QgsMapLayer *layer )
@@ -110,21 +116,24 @@ void QgsFieldExpressionWidget::setLayer( QgsMapLayer *layer )
 
 void QgsFieldExpressionWidget::setLayer( QgsVectorLayer *layer )
 {
-  mFieldModel->setLayer( layer );
+  mFieldProxyModel->sourceFieldModel()->setLayer( layer );
 }
 
 void QgsFieldExpressionWidget::setField( const QString fieldName )
 {
   if ( fieldName.isEmpty() )
     return;
 
-  QModelIndex idx = mFieldModel->indexFromName( fieldName );
+  QModelIndex idx = mFieldProxyModel->sourceFieldModel()->indexFromName( fieldName );
   if ( !idx.isValid() )
   {
     // new expression
-    idx = mFieldModel->setExpression( fieldName );
+    idx = mFieldProxyModel->sourceFieldModel()->setExpression( fieldName );
   }
-  mCombo->setCurrentIndex( idx.row() );
+
+  QModelIndex proxyIndex = mFieldProxyModel->mapFromSource( idx );
+
+  mCombo->setCurrentIndex( proxyIndex.row() );
 
   currentFieldChanged();
 }
@@ -159,7 +168,7 @@ void QgsFieldExpressionWidget::expressionEdited( const QString expression )
 void QgsFieldExpressionWidget::expressionEditingFinished()
 {
   const QString expression = mCombo->lineEdit()->text();
-  QModelIndex idx = mFieldModel->setExpression( expression );
+  QModelIndex idx = mFieldProxyModel->sourceFieldModel()->setExpression( expression );
   mCombo->setCurrentIndex( idx.row() );
   currentFieldChanged();
 }