Resizing an activation

Chapter 5 Building Dynamic Diagrams

You may want to resize an activation by pulling the top or bottom of the activation symbol. This will resize the activation vertically.

When you resize an activation, the following rules apply:

A Procedure Call message is always attached to the top of the activation on the receiver lifeline. The Procedure Call message stays at the top of the activation if the activation is moved up, or resized upwards.
A Return message is always attached to the bottom of the activation on the sender lifeline. The Return message stays at the bottom of the activation if the activation is moved down.
Messages that are covered by the activation after resizing are not automatically attached to the activation.

To change the activation of a message, press ctrl and click to select the begin or endpoint of the message and drag it onto another activation.