30  const QString expr = mFilters[layerId];
 
   31  if ( !expr.isEmpty() )
 
 
   46  filter->mFilters = mFilters;
 
 
   52  mFilters[layerId] = filter.
dump();
 
 
Handles parsing and evaluation of expressions (formerly called "search strings").
 
QString dump() const
Returns an expression string, constructed from the internal abstract syntax tree.
 
A feature filter provider allowing to set filter expressions on a per-layer basis.
 
QgsFeatureExpressionFilterProvider * clone() const override
Create a clone of the feature filter provider.
 
QStringList layerAttributes(const QgsVectorLayer *layer, const QStringList &attributes) const override
Returns the list of visible attribute names from a list of attributes names for the given layer.
 
QgsFeatureExpressionFilterProvider()=default
Constructor.
 
void setFilter(const QString &layerId, const QgsExpression &expression)
Set a filter for the given layer.
 
Q_DECL_DEPRECATED void filterFeatures(const QgsVectorLayer *layer, QgsFeatureRequest &filterFeatures) const override
Add additional filters to the feature request to further restrict the features returned by the reques...
 
Wraps a request for features to a vector layer (or directly its vector data provider).
 
Represents a vector layer which manages a vector based dataset.