Representing loops in a UML activity diagram

uml

Solution

Look further down the page you link to for Expansion Region. Use one with the iterative keyword.

An expansion region is a structured activity region that executes multiple times. Input and output expansion nodes are drawn as a group of three boxes representing a multiple selection of items. The keyword "iterative", "parallel" or "stream" is shown in the top left corner of the region.

Problem

I am trying to design an activity diagram (UML) for a networked tic tac toe game that I developed, with sockets. I am using activity partitions (swimlanes). So, there is three partitions: Client1, Server, and Client2. The diagram is looking good, except I do not know how to represent loop structures. If you look at this link: activity diagram, and look at the last diagram on the page (Partition), that is the type of activity diagram that I am working with. Does anyone know how I can represent loops? Thanks!

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