26     , mRelation( relation )
    38   if ( mWidget && mRelation.
isValid() )
    81     w->
setSizePolicy( QSizePolicy::Expanding, QSizePolicy::Expanding );
 
bool isValid() const
Returns the validity of this relation. 
This class contains context information for attribute editor widgets. 
When showing a list of features (e.g. houses as an embedded form in a district form) ...
The feature class encapsulates a single feature including its id, geometry and a list of field/values...
QgsRelationManager * relationManager() const
const QgsRelation & relation() const
const QgsAttributeEditorContext * parentContext() const
FormMode formMode() const
Returns the form mode. 
static QgsProject * instance()
Returns the QgsProject singleton instance. 
QgsRelation relation(const QString &id) const
Get access to a relation by its id. 
Represents a vector layer which manages a vector based data sets. 
QString name() const
Returns a human readable name for this relation. 
A form was embedded as a widget on another form.