add constraint description

Author: pblottiere

python/core/qgseditformconfig.sip

@@ -492,6 +492,22 @@ class QgsEditFormConfig : QObject
      */
     void setExpression( int idx, const QString& str );
 
+    /**
+     * Returns the constraint expression description of a specific filed.
+     * @param idx The index of the field
+     * @return the expression description
+     * @note added in QGIS 2.16
+     */
+    QString expressionDescription( int idx ) const;
+
+    /**
+     * Set the constraint expression description for a specific field.
+     * @param idx The index of the field
+     * @param descr The description of the expression
+     * @note added in QGIS 2.16
+     */
+    void setExpressionDescription( int idx, const QString &descr );
+
     /**
      * Returns if the field at fieldidx should be treated as NOT NULL value
      */

python/gui/editorwidgets/core/qgseditorwidgetwrapper.sip

@@ -115,6 +115,7 @@ class QgsEditorWidgetWrapper : QgsWidgetWrapper
      * Emit this signal when the constraint status changed.
      * @brief constraintStatusChanged
      * @param constraint represented as a string
+     * @param desc is the constraint description
      * @param err the error represented as a string. Empty if none.
      * @param status
      */

src/app/qgsattributetypedialog.cpp

@@ -180,6 +180,16 @@ bool QgsAttributeTypeDialog::labelOnTop() const
   return labelOnTopCheckBox->isChecked();
 }
 
+void QgsAttributeTypeDialog::setExpressionDescription( const QString &desc )
+{
+  constraintExpressionDescription->setText( desc );
+}
+
+QString QgsAttributeTypeDialog::expressionDescription()
+{
+  return constraintExpressionDescription->text();
+}
+
 bool QgsAttributeTypeDialog::notNull() const
 {
   return notNullCheckBox->isChecked();

src/app/qgsattributetypedialog.h

@@ -85,7 +85,7 @@ class APP_EXPORT QgsAttributeTypeDialog: public QDialog, private Ui::QgsAttribut
     bool fieldEditable() const;
 
     /**
-     * Getter for checkbox for not null
+     * Setter for checkbox for not null
      */
     void setNotNull( bool notNull );
 
@@ -94,6 +94,20 @@ class APP_EXPORT QgsAttributeTypeDialog: public QDialog, private Ui::QgsAttribut
      */
     bool notNull() const;
 
+    /*
+     * Setter for constraint expression description
+     * @param desc the expression description
+     * @note added in QGIS 2.16
+     **/
+    void setExpressionDescription( const QString &desc );
+
+    /*
+     * Getter for constraint expression description
+     * @return the expression description
+     * @note added in QGIS 2.16
+     **/
+    QString expressionDescription();
+
     /**
      * Getter for the constraint expression
      * @note added in QGIS 2.16

src/app/qgsfieldsproperties.cpp

@@ -529,6 +529,7 @@ void QgsFieldsProperties::attributeTypeDialog()
   attributeTypeDialog.setLabelOnTop( cfg.mLabelOnTop );
   attributeTypeDialog.setNotNull( cfg.mNotNull );
   attributeTypeDialog.setExpression( cfg.mConstraint );
+  attributeTypeDialog.setExpressionDescription( cfg.mConstraintDescription );
 
   attributeTypeDialog.setWidgetV2Config( cfg.mEditorWidgetV2Config );
   attributeTypeDialog.setWidgetV2Type( cfg.mEditorWidgetV2Type );
@@ -539,6 +540,7 @@ void QgsFieldsProperties::attributeTypeDialog()
   cfg.mEditable = attributeTypeDialog.fieldEditable();
   cfg.mLabelOnTop = attributeTypeDialog.labelOnTop();
   cfg.mNotNull = attributeTypeDialog.notNull();
+  cfg.mConstraintDescription = attributeTypeDialog.expressionDescription();
   cfg.mConstraint = attributeTypeDialog.expression();
 
   cfg.mEditorWidgetV2Type = attributeTypeDialog.editorWidgetV2Type();
@@ -913,6 +915,7 @@ void QgsFieldsProperties::apply()
     mLayer->editFormConfig()->setReadOnly( i, !cfg.mEditable );
     mLayer->editFormConfig()->setLabelOnTop( i, cfg.mLabelOnTop );
     mLayer->editFormConfig()->setNotNull( i, cfg.mNotNull );
+    mLayer->editFormConfig()->setExpressionDescription( i, cfg.mConstraintDescription );
     mLayer->editFormConfig()->setExpression( i, cfg.mConstraint );
 
     mLayer->editFormConfig()->setWidgetType( idx, cfg.mEditorWidgetV2Type );
@@ -981,6 +984,7 @@ QgsFieldsProperties::FieldConfig::FieldConfig()
     , mEditableEnabled( true )
     , mLabelOnTop( false )
     , mNotNull( false )
+    , mConstraintDescription( QString() )
     , mButton( nullptr )
 {
 }
@@ -994,6 +998,7 @@ QgsFieldsProperties::FieldConfig::FieldConfig( QgsVectorLayer* layer, int idx )
   mLabelOnTop = layer->editFormConfig()->labelOnTop( idx );
   mNotNull = layer->editFormConfig()->notNull( idx );
   mConstraint = layer->editFormConfig()->expression( idx );
+  mConstraintDescription = layer->editFormConfig()->expressionDescription( idx );
   mEditorWidgetV2Type = layer->editFormConfig()->widgetType( idx );
   mEditorWidgetV2Config = layer->editFormConfig()->widgetConfig( idx );
 

src/app/qgsfieldsproperties.h

@@ -94,6 +94,7 @@ class APP_EXPORT QgsFieldsProperties : public QWidget, private Ui_QgsFieldsPrope
         bool mLabelOnTop;
         bool mNotNull;
         QString mConstraint;
+        QString mConstraintDescription;
         QPushButton* mButton;
         QString mEditorWidgetV2Type;
         QMap<QString, QVariant> mEditorWidgetV2Config;

src/core/qgseditformconfig.cpp

@@ -135,6 +135,22 @@ void QgsEditFormConfig::setExpression( int idx, const QString& str )
     mConstraints[ mFields.at( idx ).name()] = str;
 }
 
+QString QgsEditFormConfig::expressionDescription( int idx ) const
+{
+  QString description;
+
+  if ( idx >= 0 && idx < mFields.count() )
+    description = mConstraintsDescription[ mFields.at( idx ).name()];
+
+  return description;
+}
+
+void QgsEditFormConfig::setExpressionDescription( int idx, const QString &descr )
+{
+  if ( idx >= 0 && idx < mFields.count() )
+    mConstraintsDescription[ mFields.at( idx ).name()] = descr;
+}
+
 bool QgsEditFormConfig::notNull( int idx ) const
 {
   if ( idx >= 0 && idx < mFields.count() )

src/core/qgseditformconfig.h

@@ -484,12 +484,12 @@ class CORE_EXPORT QgsEditFormConfig : public QObject
     QgsEditorWidgetConfig widgetConfig( const QString& widgetName ) const;
 
     /**
-     * Remove the configuration for the editor widget used to represent the field at the given index
-     *
-     * @param fieldIdx  The index of the field
-     *
-     * @return true if successful, false if the field does not exist
-     */
+    * Remove the configuration for the editor widget used to represent the field at the given index
+    *
+    * @param fieldIdx  The index of the field
+    *
+    * @return true if successful, false if the field does not exist
+    */
     bool removeWidgetConfig( int fieldIdx );
 
     /**
@@ -528,6 +528,22 @@ class CORE_EXPORT QgsEditFormConfig : public QObject
      */
     void setExpression( int idx, const QString& str );
 
+    /**
+     * Returns the constraint expression description of a specific filed.
+     * @param idx The index of the field
+     * @return the expression description
+     * @note added in QGIS 2.16
+     */
+    QString expressionDescription( int idx ) const;
+
+    /**
+     * Set the constraint expression description for a specific field.
+     * @param idx The index of the field
+     * @param descr The description of the expression
+     * @note added in QGIS 2.16
+     */
+    void setExpressionDescription( int idx, const QString &descr );
+
     /**
      * Returns if the field at fieldidx should be treated as NOT NULL value
      */
@@ -657,6 +673,7 @@ class CORE_EXPORT QgsEditFormConfig : public QObject
     QList< TabData > mTabs;
 
     QMap< QString, QString> mConstraints;
+    QMap< QString, QString> mConstraintsDescription;
     QMap< QString, bool> mFieldEditables;
     QMap< QString, bool> mLabelOnTop;
     QMap< QString, bool> mNotNull;

src/gui/editorwidgets/core/qgseditorwidgetregistry.cpp

@@ -253,6 +253,7 @@ void QgsEditorWidgetRegistry::readMapLayer( QgsMapLayer* mapLayer, const QDomEle
       vectorLayer->editFormConfig()->setLabelOnTop( idx, ewv2CfgElem.attribute( "labelOnTop", "0" ) == "1" );
       vectorLayer->editFormConfig()->setNotNull( idx, ewv2CfgElem.attribute( "notNull", "0" ) == "1" );
       vectorLayer->editFormConfig()->setExpression( idx, ewv2CfgElem.attribute( "constraint", QString() ) );
+      vectorLayer->editFormConfig()->setExpressionDescription( idx, ewv2CfgElem.attribute( "constraintDescription", QString() ) );
 
       vectorLayer->editFormConfig()->setWidgetConfig( idx, cfg );
     }
@@ -312,6 +313,7 @@ void QgsEditorWidgetRegistry::writeMapLayer( QgsMapLayer* mapLayer, QDomElement&
       ewv2CfgElem.setAttribute( "labelOnTop", vectorLayer->editFormConfig()->labelOnTop( idx ) );
       ewv2CfgElem.setAttribute( "notNull", vectorLayer->editFormConfig()->notNull( idx ) );
       ewv2CfgElem.setAttribute( "constraint", vectorLayer->editFormConfig()->expression( idx ) );
+      ewv2CfgElem.setAttribute( "constraintDescription", vectorLayer->editFormConfig()->expressionDescription( idx ) );
 
       mWidgetFactories[widgetType]->writeConfig( vectorLayer->editFormConfig()->widgetConfig( idx ), ewv2CfgElem, doc, vectorLayer, idx );
 

src/gui/editorwidgets/core/qgseditorwidgetwrapper.cpp

@@ -108,10 +108,13 @@ void QgsEditorWidgetWrapper::updateConstraint( const QgsFeature &ft )
   bool toEmit( false );
   QString errStr( tr( "predicate is True" ) );
   QString expression = layer()->editFormConfig()->expression( mFieldIdx );
+  QString description;
   QVariant value = ft.attribute( mFieldIdx );
 
   if ( ! expression.isEmpty() )
   {
+    description = layer()->editFormConfig()->expressionDescription( mFieldIdx );
+
     QgsExpressionContext context =
       QgsExpressionContextUtils::createFeatureBasedContext( ft, *ft.fields() );
     context << QgsExpressionContextUtils::layerScope( layer() );
@@ -139,9 +142,13 @@ void QgsEditorWidgetWrapper::updateConstraint( const QgsFeature &ft )
     {
       QString fieldName = ft.fields()->field( mFieldIdx ).name();
       expression = "( " + expression + " ) AND ( " + fieldName + " IS NOT NULL)";
+      description = "( " + description + " ) AND NotNull";
     }
     else
+    {
+      description = "NotNull";
       expression = "NotNull";
+    }
 
     mValidConstraint = mValidConstraint && !value.isNull();
 
@@ -154,7 +161,7 @@ void QgsEditorWidgetWrapper::updateConstraint( const QgsFeature &ft )
   if ( toEmit )
   {
     updateConstraintWidgetStatus();
-    emit constraintStatusChanged( expression, errStr, mValidConstraint );
+    emit constraintStatusChanged( expression, description, errStr, mValidConstraint );
   }
 }