Add not null constraint and visual feedback to widgets

python/core/qgseditformconfig.sip

@@ -474,7 +474,16 @@ class QgsEditFormConfig : QObject
     /**
      * If set to false, the widget at the given index will be read-only.
      */
-    void setReadOnly(int idx, bool readOnly );
+    void setReadOnly( int idx, bool readOnly = true );
+
+    /**
+     * Returns if the field at fieldidx should be treated as NOT NULL value
+     */
+    bool notNull( int fieldidx) const;
+    /**
+     * Set if the field at fieldidx should be treated as NOT NULL value
+     */
+    void setNotNull( int idx, bool notnull = true );
 
     /**
      * If this returns true, the widget at the given index will receive its label on the previous line

python/core/qgsfield.sip

@@ -165,7 +165,7 @@ class QgsField
     /* Raise an exception if the arguments couldn't be parsed. */
     sipNoMethod(sipParseErr, sipName_QgsField, sipName_convertCompatible, doc_QgsField_convertCompatible);
 
-    return NULL;
+    return nullptr;
 %End
 
     //! Allows direct construction of QVariants from fields.

src/app/qgsattributetypedialog.cpp

@@ -163,16 +163,26 @@ void QgsAttributeTypeDialog::setWidgetV2Config( const QgsEditorWidgetConfig& con
   mWidgetV2Config = config;
 }
 
-bool QgsAttributeTypeDialog::fieldEditable()
+bool QgsAttributeTypeDialog::fieldEditable() const
 {
   return isFieldEditableCheckBox->isChecked();
 }
 
-bool QgsAttributeTypeDialog::labelOnTop()
+void QgsAttributeTypeDialog::setNotNull( bool notnull )
+{
+  notNullCheckBox->setChecked( notnull );
+}
+
+bool QgsAttributeTypeDialog::labelOnTop() const
 {
   return labelOnTopCheckBox->isChecked();
 }
 
+bool QgsAttributeTypeDialog::notNull() const
+{
+  return notNullCheckBox->isChecked();
+}
+
 void QgsAttributeTypeDialog::setFieldEditable( bool editable )
 {
   isFieldEditableCheckBox->setChecked( editable );

src/app/qgsattributetypedialog.h

@@ -69,6 +69,11 @@ class APP_EXPORT QgsAttributeTypeDialog: public QDialog, private Ui::QgsAttribut
      */
     void setLabelOnTop( bool onTop );
 
+    /**
+     * Getter for checkbox for label on top of field
+     */
+    bool labelOnTop() const;
+
     /**
      * Setter for checkbox for editable state of field
      */
@@ -77,12 +82,17 @@ class APP_EXPORT QgsAttributeTypeDialog: public QDialog, private Ui::QgsAttribut
     /**
      * Getter for checkbox for editable state of field
      */
-    bool fieldEditable();
+    bool fieldEditable() const;
 
     /**
-     * Getter for checkbox for label on top of field
+     * Getter for checkbox for not null
+     */
+    void setNotNull( bool notnull );
+
+    /**
+     * Getter for checkbox for not null
      */
-    bool labelOnTop();
+    bool notNull() const;
 
   private slots:
     /**

src/app/qgsfieldsproperties.cpp

@@ -527,6 +527,7 @@ void QgsFieldsProperties::attributeTypeDialog()
 
   attributeTypeDialog.setFieldEditable( cfg.mEditable );
   attributeTypeDialog.setLabelOnTop( cfg.mLabelOnTop );
+  attributeTypeDialog.setNotNull( cfg.mNotNull );
 
   attributeTypeDialog.setWidgetV2Config( cfg.mEditorWidgetV2Config );
   attributeTypeDialog.setWidgetV2Type( cfg.mEditorWidgetV2Type );
@@ -536,6 +537,7 @@ void QgsFieldsProperties::attributeTypeDialog()
 
   cfg.mEditable = attributeTypeDialog.fieldEditable();
   cfg.mLabelOnTop = attributeTypeDialog.labelOnTop();
+  cfg.mNotNull = attributeTypeDialog.notNull();
 
   cfg.mEditorWidgetV2Type = attributeTypeDialog.editorWidgetV2Type();
   cfg.mEditorWidgetV2Config = attributeTypeDialog.editorWidgetV2Config();
@@ -908,6 +910,7 @@ void QgsFieldsProperties::apply()
 
     mLayer->editFormConfig()->setReadOnly( i, !cfg.mEditable );
     mLayer->editFormConfig()->setLabelOnTop( i, cfg.mLabelOnTop );
+    mLayer->editFormConfig()->setNotNull( i, cfg.mNotNull );
 
     mLayer->editFormConfig()->setWidgetType( idx, cfg.mEditorWidgetV2Type );
     mLayer->editFormConfig()->setWidgetConfig( idx, cfg.mEditorWidgetV2Config );
@@ -974,6 +977,7 @@ QgsFieldsProperties::FieldConfig::FieldConfig()
     : mEditable( true )
     , mEditableEnabled( true )
     , mLabelOnTop( false )
+    , mNotNull( false )
     , mButton( nullptr )
 {
 }
@@ -985,6 +989,7 @@ QgsFieldsProperties::FieldConfig::FieldConfig( QgsVectorLayer* layer, int idx )
   mEditableEnabled = layer->fields().fieldOrigin( idx ) != QgsFields::OriginJoin
                      && layer->fields().fieldOrigin( idx ) != QgsFields::OriginExpression;
   mLabelOnTop = layer->editFormConfig()->labelOnTop( idx );
+  mNotNull = layer->editFormConfig()->notNull( idx );
   mEditorWidgetV2Type = layer->editFormConfig()->widgetType( idx );
   mEditorWidgetV2Config = layer->editFormConfig()->widgetConfig( idx );
 

src/app/qgsfieldsproperties.h

@@ -92,6 +92,7 @@ class APP_EXPORT QgsFieldsProperties : public QWidget, private Ui_QgsFieldsPrope
         bool mEditable;
         bool mEditableEnabled;
         bool mLabelOnTop;
+        bool mNotNull;
         QPushButton* mButton;
         QString mEditorWidgetV2Type;
         QMap<QString, QVariant> mEditorWidgetV2Config;

src/core/qgseditformconfig.cpp

@@ -119,6 +119,14 @@ bool QgsEditFormConfig::labelOnTop( int idx ) const
     return false;
 }
 
+bool QgsEditFormConfig::notNull( int idx ) const
+{
+  if ( idx >= 0 && idx < mFields.count() )
+    return mNotNull.value( mFields.at( idx ).name(), false );
+  else
+    return false;
+}
+
 void QgsEditFormConfig::setReadOnly( int idx, bool readOnly )
 {
   if ( idx >= 0 && idx < mFields.count() )
@@ -131,6 +139,12 @@ void QgsEditFormConfig::setLabelOnTop( int idx, bool onTop )
     mLabelOnTop[ mFields.at( idx ).name()] = onTop;
 }
 
+void QgsEditFormConfig::setNotNull( int idx, bool notnull )
+{
+  if ( idx >= 0 && idx < mFields.count() )
+    mNotNull[ mFields.at( idx ).name()] = notnull;
+}
+
 void QgsEditFormConfig::readXml( const QDomNode& node )
 {
   QDomNode editFormNode = node.namedItem( "editform" );
@@ -280,7 +294,6 @@ void QgsEditFormConfig::writeXml( QDomNode& node ) const
   efifpField.appendChild( doc.createTextNode( QgsProject::instance()->writePath( initFilePath() ) ) );
   node.appendChild( efifpField );
 
-
   QDomElement eficField  = doc.createElement( "editforminitcode" );
   eficField.appendChild( doc.createCDATASection( initCode() ) );
   node.appendChild( eficField );
@@ -337,6 +350,7 @@ void QgsEditFormConfig::writeXml( QDomNode& node ) const
     {
       QDomElement widgetElem = doc.createElement( "widget" );
       widgetElem.setAttribute( "name", configIt.key() );
+      // widgetElem.setAttribute( "notNull",  );
 
       QDomElement configElem = doc.createElement( "config" );
       widgetElem.appendChild( configElem );

src/core/qgseditformconfig.h

@@ -512,6 +512,15 @@ class CORE_EXPORT QgsEditFormConfig : public QObject
      */
     void setReadOnly( int idx, bool readOnly = true );
 
+    /**
+     * Returns if the field at fieldidx should be treated as NOT NULL value
+     */
+    bool notNull( int fieldidx ) const;
+    /**
+     * Set if the field at fieldidx should be treated as NOT NULL value
+     */
+    void setNotNull( int idx, bool notnull = true );
+
     /**
      * If this returns true, the widget at the given index will receive its label on the previous line
      * while if it returns false, the widget will receive its label on the left hand side.
@@ -633,6 +642,7 @@ class CORE_EXPORT QgsEditFormConfig : public QObject
 
     QMap< QString, bool> mFieldEditables;
     QMap< QString, bool> mLabelOnTop;
+    QMap< QString, bool> mNotNull;
 
     QMap<QString, QString> mEditorWidgetV2Types;
     QMap<QString, QgsEditorWidgetConfig > mWidgetConfigs;

src/core/qgseditorwidgetconfig.h

@@ -16,6 +16,8 @@
 #include <QString>
 #include <QVariant>
 
+#ifndef QGSEDITORWIDGETCONFIG_H
+#define QGSEDITORWIDGETCONFIG_H
 
 /**
  * Holds a set of configuration parameters for a editor widget wrapper.
@@ -30,4 +32,6 @@
  * You get these passed, for every new widget wrapper.
  */
 
-typedef QMap<QString, QVariant> QgsEditorWidgetConfig;
+typedef QVariantMap QgsEditorWidgetConfig;
+
+#endif // QGSEDITORWIDGETCONFIG_H

src/core/qgsfeature.cpp

@@ -288,6 +288,12 @@ int QgsFeature::fieldNameIndex( const QString& fieldName ) const
   return d->fields.fieldNameIndex( fieldName );
 }
 
+/***************************************************************************
+ * This class is considered CRITICAL and any change MUST be accompanied with
+ * full unit tests in testqgsfeature.cpp.
+ * See details in QEP #17
+ ****************************************************************************/
+
 QDataStream& operator<<( QDataStream& out, const QgsFeature& feature )
 {
   out << feature.id();

src/core/qgsvectorlayer.cpp

@@ -1105,13 +1105,13 @@ QgsFeatureIterator QgsVectorLayer::getFeatures( const QgsFeatureRequest& request
 }
 
 
-bool QgsVectorLayer::addFeature( QgsFeature& f, bool alsoUpdateExtent )
+bool QgsVectorLayer::addFeature( QgsFeature& feature, bool alsoUpdateExtent )
 {
   Q_UNUSED( alsoUpdateExtent ); // TODO[MD]
   if ( !mValid || !mEditBuffer || !mDataProvider )
     return false;
 
-  bool success = mEditBuffer->addFeature( f );
+  bool success = mEditBuffer->addFeature( feature );
 
   if ( success )
     updateExtents();

src/core/qgsvectorlayer.h

@@ -975,11 +975,11 @@ class CORE_EXPORT QgsVectorLayer : public QgsMapLayer
     QgsFeatureIterator getFeatures( const QgsFeatureRequest& request = QgsFeatureRequest() );
 
     /** Adds a feature
-        @param f feature to add
+        @param feature feature to add
         @param alsoUpdateExtent If True, will also go to the effort of e.g. updating the extents.
         @return                    True in case of success and False in case of error
      */
-    bool addFeature( QgsFeature& f, bool alsoUpdateExtent = true );
+    bool addFeature( QgsFeature& feature, bool alsoUpdateExtent = true );
 
     /** Updates an existing feature. This method needs to query the datasource
         on every call. Consider using {@link changeAttributeValue()} or

src/gui/editorwidgets/core/qgseditorwidgetregistry.cpp

@@ -251,6 +251,7 @@ void QgsEditorWidgetRegistry::readMapLayer( QgsMapLayer* mapLayer, const QDomEle
 
       vectorLayer->editFormConfig()->setReadOnly( idx, ewv2CfgElem.attribute( "fieldEditable", "1" ) != "1" );
       vectorLayer->editFormConfig()->setLabelOnTop( idx, ewv2CfgElem.attribute( "labelOnTop", "0" ) == "1" );
+      vectorLayer->editFormConfig()->setNotNull( idx, ewv2CfgElem.attribute( "notNull", "0" ) == "1" );
       vectorLayer->editFormConfig()->setWidgetConfig( idx, cfg );
     }
     else
@@ -307,6 +308,7 @@ void QgsEditorWidgetRegistry::writeMapLayer( QgsMapLayer* mapLayer, QDomElement&
       QDomElement ewv2CfgElem = doc.createElement( "widgetv2config" );
       ewv2CfgElem.setAttribute( "fieldEditable", !vectorLayer->editFormConfig()->readOnly( idx ) );
       ewv2CfgElem.setAttribute( "labelOnTop", vectorLayer->editFormConfig()->labelOnTop( idx ) );
+      ewv2CfgElem.setAttribute( "notNull", vectorLayer->editFormConfig()->notNull( idx ) );
 
       mWidgetFactories[widgetType]->writeConfig( vectorLayer->editFormConfig()->widgetConfig( idx ), ewv2CfgElem, doc, vectorLayer, idx );
 

src/gui/editorwidgets/core/qgseditorwidgetwrapper.cpp

@@ -24,6 +24,7 @@ QgsEditorWidgetWrapper::QgsEditorWidgetWrapper( QgsVectorLayer* vl, int fieldIdx
     : QgsWidgetWrapper( vl, editor, parent )
     , mFieldIdx( fieldIdx )
 {
+  connect( this, SIGNAL( valueChanged( QVariant ) ), this, SLOT( onValueChanged( QVariant ) ) );
 }
 
 int QgsEditorWidgetWrapper::fieldIdx() const
@@ -61,6 +62,7 @@ void QgsEditorWidgetWrapper::setEnabled( bool enabled )
 void QgsEditorWidgetWrapper::setFeature( const QgsFeature& feature )
 {
   setValue( feature.attribute( mFieldIdx ) );
+  onValueChanged( value() );
 }
 
 void QgsEditorWidgetWrapper::valueChanged( const QString& value )
@@ -92,3 +94,28 @@ void QgsEditorWidgetWrapper::valueChanged()
 {
   emit valueChanged( value() );
 }
+
+void QgsEditorWidgetWrapper::updateConstraintsOk( bool constraintStatus )
+{
+  if ( constraintStatus )
+  {
+    widget()->setStyleSheet( "" );
+  }
+  else
+  {
+    widget()->setStyleSheet( "QWidget{ background-color: '#dd7777': }" );
+  }
+}
+
+void QgsEditorWidgetWrapper::onValueChanged( const QVariant& value )
+{
+  if ( layer()->editFormConfig()->notNull( mFieldIdx ) )
+  {
+    if ( value.isNull() != mIsNull )
+    {
+      updateConstraintsOk( value.isNull() );
+      emit constraintStatusChanged( "NotNull", !value.isNull() );
+      mIsNull = value.isNull();
+    }
+  }
+}

src/gui/editorwidgets/core/qgseditorwidgetwrapper.h

@@ -118,6 +118,13 @@ class GUI_EXPORT QgsEditorWidgetWrapper : public QgsWidgetWrapper
      */
     void valueChanged( const QVariant& value );
 
+    /**
+     * @brief constraintStatusChanged
+     * @param constraint
+     * @param status
+     */
+    void constraintStatusChanged( const QString& constraint, bool status );
+
   public slots:
     /**
      * Will be called when the feature changes
@@ -185,8 +192,28 @@ class GUI_EXPORT QgsEditorWidgetWrapper : public QgsWidgetWrapper
      */
     void valueChanged();
 
+  private:
+    /**
+     * This should update the widget with a visual cue if a constraint status
+     * changed.
+     *
+     * By default a stylesheet will be applied on the widget that changes the
+     * background color to red.
+     *
+     * This can be overwritten in subclasses to allow individual widgets to
+     * change the visual cue.
+     */
+    virtual void updateConstraintsOk( bool constraintStatus );
+
+  private slots:
+    /**
+     * @brief mFieldIdx
+     */
+    void onValueChanged( const QVariant& value );
+
   private:
     int mFieldIdx;
+    bool mIsNull;
 };
 
 // We'll use this class inside a QVariant in the widgets properties

src/gui/editorwidgets/qgsrangewidgetfactory.cpp

@@ -38,7 +38,7 @@ QgsEditorWidgetConfig QgsRangeWidgetFactory::readConfig( const QDomElement& conf
 {
   Q_UNUSED( layer );
   Q_UNUSED( fieldIdx );
-  QMap<QString, QVariant> cfg;
+  QgsEditorWidgetConfig cfg;
 
   cfg.insert( "Style", configElement.attribute( "Style" ) );
   cfg.insert( "Min", configElement.attribute( "Min" ) );

src/gui/editorwidgets/qgsrelationreferenceconfigdlg.cpp

@@ -55,7 +55,7 @@ QgsRelationReferenceConfigDlg::QgsRelationReferenceConfigDlg( QgsVectorLayer* vl
   }
 }
 
-void QgsRelationReferenceConfigDlg::setConfig( const QMap<QString, QVariant>& config )
+void QgsRelationReferenceConfigDlg::setConfig( const QgsEditorWidgetConfig& config )
 {
   if ( config.contains( "AllowNULL" ) )
   {

src/gui/editorwidgets/qgsrelationreferencefactory.cpp

@@ -46,7 +46,7 @@ QgsEditorWidgetConfig QgsRelationReferenceFactory::readConfig( const QDomElement
 {
   Q_UNUSED( layer );
   Q_UNUSED( fieldIdx );
-  QMap<QString, QVariant> cfg;
+  QgsEditorWidgetConfig cfg;
 
   cfg.insert( "AllowNULL", configElement.attribute( "AllowNULL" ) == "1" );
   cfg.insert( "OrderByValue", configElement.attribute( "OrderByValue" ) == "1" );