To move a class from a cluster to another one, you have to use the
Diagram tool. First,
center the tool on the cluster that contains the class you want to move. Then, if the destination cluster is not shown on the diagram,
pick it in the
cluster tool and drop it in the
diagram. Once both clusters are displayed, you just have to drag the class to its destination.
See Also
Find where a class is
Find where a cluster is