The Attribute tab lists the names of all the attributes defined for a part. An attribute represents a property of a part. These properties can be actual data objects stored in an instance variable or class variable (such as the contents of an entry field), or computed objects (such as the sum of all numbers in an array).

You can connect attributes to attributes or actions of other parts. To connect an attribute, you make the connection to its name. You can use a get selector to request the return value of an attribute, or a set selector to set the value. The part may also need to signal other parts that the attribute has been changed.

Using the Attribute tab, you can quickly specify instance or class variables for a class, and generate code for get or set selectors.