Step by step guide to draw Class diagram in Enterprise Architect

1. Prepared By: J.Chandra Priya, TF, DCT, MIT.
In your project browser first click on the new diagram icon:
Then select ‘UML Behavioral’ from the type column and ‘Sequence’ from the Diagram Type
column:

2. Prepared By: J.Chandra Priya, TF, DCT, MIT.
Drag an actor on to the drawing area:

3. Prepared By: J.Chandra Priya, TF, DCT, MIT.
And then a lifeline:

4. Prepared By: J.Chandra Priya, TF, DCT, MIT.
To draw an arrow between the actor an lifeline, select the actor, so that an upwards-facing arrow
becomes visible beside it:

5. Prepared By: J.Chandra Priya, TF, DCT, MIT.
Click on this arrow, dragging it over to the lifeline:

6. Prepared By: J.Chandra Priya, TF, DCT, MIT.
To add another lifeline, do the same as before by selecting it from the toolbox and dragging it over to
the target destination. Ditto adding a new link between the first and second lifeline objects.

7. Prepared By: J.Chandra Priya, TF, DCT, MIT.
To lower the second object, double click on the arrow between them,
select lifecycle -> New and give it a massage and press OK:

8. Prepared By: J.Chandra Priya, TF, DCT, MIT.
And notice that the second item drops down lower, and the line between becomes dashed:

9. Prepared By: J.Chandra Priya, TF, DCT, MIT.
Feel free to now to draw a few more interactions in exactly the same was as described above: select
the source object and its arrow, and drag to the target object:
To insert a gaps between message exchanges, I right click on the lower link in this example and
select Activations -> Start new message group: Which results in the desired gap:

10. Prepared By: J.Chandra Priya, TF, DCT, MIT.
To show self-activity, click on the item’s arrow and drag it back on to the same lifeline. Double click
on it in order to set its message: