public PropertyFreehand Gets or sets a value indicating whether this EditorWidget is using freehand draw mode when using Add, Reshape, Union and Cut.
But can't see the Add icon inside the widget but Add Selection found.
If adding a graphic/shape is not belong to EditorWidget, would you guide me on what part of the API Reference or specifically of what class/widget to look for?
If you are using ArcGIS Server 10 where feature services editing can be enabled, you can create a FeatureLayer with this REST endpoint as URL, EditorWidget can work against this layer when you set EditorWidget.Map property and set FeatureLayer.ID.
If you click on the "..." button, this expands Add options and you can check Freehand, this applies to Polyline/Polygon geometries. Select one of the templates from the Polygon layer and start drawing.