Data Management Capabilities > Managing Part Structures > Windchill Options and Variants Capabilities > Developing Advanced Selection Logic for Configurable Modules > Basic Steps for Defining Advanced Selection > Adding a Constraint > External Application Constraint Editor
External Application Constraint Editor
The External Application Constraint Editor allows you to select a class name and appropriate input and output parameters that will be used to evaluate a constraint.
To create a constraint using the External Application Constraint Editor:
1. Click the ellipsis next to the class name field to select the class from which you want to derive your inputs. A window appears allowing you to select the class.
2. Specify whether the class is a singleton.
3. Select the input parameters for the constraint.
4. Select the output parameters for the constraint.
5. Click Apply to apply the constraint.