In sequence diagrams, you can add create, destroy,
synchronous and asynchronous messages to lifelines to represent communication
between objects. You can also specify the signatures of messages.
- In the Palette, click a message
type.
- In the interaction frame, click a source lifeline and
drag the cursor to a target lifeline.
- Type a name for the message.
If you create a synchronous message, a return message is created automatically.
Note: You can delay an asynchronous message by dragging the asynchronous
message first horizontally and then vertically across existing messages to
the target lifeline where you want to terminate the message.
Tip: You
can also assign an operation to a message in an existing diagram. In the navigation
view, click an operation and drag it onto a message in the interaction frame.
The operation must belong to the target instance of the object or be visible
to and in scope of the operation in an object.