Any class diagram created in a package fragment root is a specific
diagram dedicated to show the packages and their relationships. The
other class diagrams (created in packages) can also work with packages
but they must be explicitly inserted in the diagram.
The following screenshot shows an example. Three packages are represented with their dependencies :
gui. Here the package
gui depends on
process, while the
package depends on the
Classes (and Interfaces) can be inserted in the packages by using the contextual menu item Insert > Class (or Insert > Interface) on the package.
A dialog box proposes to choose one the packages classes (or interfaces).
Once chosen, the class (or interface) appears in the package view.