A Message is a modeling element that defines a specific kind of communication in an Interaction. A communication can be e.g. raising a signal, invoking an Operation, creating or destroying an Instance. The Message specifies the type of communication defined by the dispatching ExecutionSpecification, as well as the sender and the receiver.
Use the following toolbar buttons to add specific message types:
Async message (Call)
Messages are sent between sender and receiver timelines, and are shown as labeled arrows.
To insert a message:
1.Click the specific message icon in the toolbar.
2.Click anywhere on the timeline sender object e.g. Idle.
3.Drag and drop the message line onto the receiver objects timeline e.g. NoCard. Lifelines are highlighted when the message can be dropped.
•The direction in which you drag the arrow defines the message direction. Reply messages can point in either direction.
•Having clicked a message icon and holding down Ctrl key, allows you to insert multiple messages by repeatedly clicking and dragging in the diagram tab.
To delete a message:
1.Click the specific message to select it.
2.Press the Del key to delete it from the model, or right click it and select "Delete from diagram".