Ignore previous completely wrong answer! Sorry. I think you call QgsVectorLayer::setEditorWidgetSetup() instead: https://qgis.org/api/classQgsVectorLayer.html#a8a174ba67d0a16f544211088656af143 Tom ----- Buy Pie Spy: Adventures in British pastry 2010-11 on Amazon -- Sent from: http://osgeo-org.1560.x6.nabble.com/QGIS-Developer-f4099106.html