The ComboBox control
The ComboBox is a simple dropdown list control that can contain either static values (for example choice column data) or values retrieved from another list (lookup column data)
If the control is bound to a choice column, then the Static Values property is automatically filled with the underlying values from the column. The property is readonly as every change in the column values will be automatically reflected in the control values.
If the control is bound to a lookup column, then the list info should be filled in.
The Site Url, List (and/or View) properties should be defined.
The normal behaviour of lookup columns is to display the Title and save the ID of the selected record.
For that reason, 2 properties can be defined in the Lookup Details tab : Display Field & Value Field.
These properties should be automatically filled when first registering PowerForms for an existing list/content type.
In order to add criteria for the list query that will provide control data, use the criteria options.
Details on how to setup criteria can be found in the following links :
List Query Criteria
Complex List Query Examples
Extra configuration tab
Set this property to TRUE to force the control to send only the Value Member value of the underlying lookup value when saving its value. Normally lookup controls that load data from other lists, use the ID;#TITLE format to save data
Defines if the results will be sorted by the Display Field
If the internal name of a column is supplied, the retrieved results will be filtered allowing unique values for that specific field