Define Conditional Styles

Now let’s make requirements appear differently on the diagram depending on their priority and status.

Right-click on the priority attribute of business requirements and select Generate class sets from the context menu:

Expand the BusinessRequirement class in the explorer, and you’ll see a new set of dynamic subclasses called Priority, containing three classes: Low, Normal, and High:

The idea behind dynamic classes is simple but powerful: they separate the essence of an entity from its current state:

• The base class (e.g., Business Requirement, Information System) is fixed. It defines the entity’s attributes and allowed relationships and cannot be changed
• Dynamic classes are derived from attribute values or relationships. For example, you can classify requirements by effort: small (up to 40 hours), medium (40–160 hours), and large (over 160 hours)

This makes it easy to highlight the most important elements in a diagram—for example, high-priority requirements with low effort that should be addressed first.

Select the Low dynamic class. In the properties panel, the Predicate field contains a logical expression that defines membership in this class.

Set colors for different priority levels:

• For Low, enter: rgb(59 130 246) in the Fill Color field
• For High, enter: rgb(239 68 68)

Notice how the shape preview updates instantly.

In the same way, generate dynamic classes for the status attribute of system requirements and assign the following colors:

• Approved — rgb(129 140 248)
• Implementation — rgb(245 158 11)
• Testing — rgb(6 182 212)
• Completed — rgb(34 197 94)

Now let’s configure styles for relationships. Generate dynamic classes for relationships based on the extended attribute. For the class representing extended implementations, set the line style to dash in the Representation section:

Open your requirements model. Change the priority of any requirement or the type of a relationship, and you’ll see the styles update instantly on the diagram:

You’re now ready to create your own modeling notations!