Drawing Sequence Diagram with Real-time Layout

When creating a complex sequence diagram, it is very troublesome and time-consuming to organize the shapes in a nice and neat layout. In VP-UML, there is a feature allowing you to enable the real-time layout adjustment while specifying the absolute or relative spacing between lifelines or messages. This feature helps you to organize the layout of your sequence diagram automatically in a real-time manner.

1. Create a new sequence diagram and draw the following sequence diagram.
   
   
   
2. Right-click on the diagram, select Adjust Layout... from the pop-up menu.
   
   
   
3. From the Adjust Layout dialog box, change the setting as shown below. Select the Enabled real-time layout check box, select the Absolute spacing radio button for the Message Spacing and set the value to 30. Select the Absolute spacing radio button for the LifeLine Spacing and set the value to 20. Click Close button to confirm the settings and close the dialog box.
   
   
   Real-time layout will be performed automatically once there is a change to the diagram content, including adding, deleting and moving a shape.

Draw more LifeLines or Messages and the spaces between them will be automatically arranged in the real-time manner as we set previously. That is, the space between two messages is kept 30 while the space between two LifeLines is 20 definitely.

Since we have set the spacing as absolute spacing, even if we move the position of the LifeLines or Messages, the space between Messages will always be 30 and space between LifeLines will always be 20 as you have set earlier. For example, moving the HeadQuarter Database LifeLine to the right will automatically re-arrange the layout so the space between Branch Database and HeadQuarter Database is 20.

Delete a LifeLine or a Message and the spaces between them will be automatically re-arranged. For example, deleting the Branch Database LifeLine will automatically re-arrange the layout so the space between Checking Account and HeadQuarter Database is 20.

1. Relative spacing refers to the ratio of distance between LifeLines or Messages. The default relative spacing is always set to 100, indicating the ratio is 100%. If we change the value, for example to 50, then the distance between LifeLines or Messages will be automatically set to 50%. For example, changing both LifeLine and Message relative ratio to 50.
   
   
   
2. Absolute spacing refers to the fixed distance between LifeLines or Messages. Regardless any changes we make in the sequence diagram (e.g. adding, deleting, moving the lifelines and/or messages), the space between Messages and LifeLines will always in the fixed distance which value we have set previously.

• Learn how to draw the sequence diagram using the resource-centric interface
  Drawing Sequence Diagram with Resource-Centric Interface
  
  
• Learn how to use alternative combined fragments in sequence diagram
  Using Alternative Combined Fragments in Sequence Diagram
  
  
• Learn how to edit the combined fragment in sequence diagram
  Editing the Combined Fragment in Sequence Diagram
  
  
• Learn how to synchronize between sequence diagram and Collaboration Diagram
  Synchronization between System Level Sequence Diagram and Collaboration Diagram
  
  
• Learn how to synchronize between sequence diagram and flow of event
  Synchronization between System Level Sequence Diagram and Flow of Event
  
  
• Get more tips on diagramming with Visual Paradigm’s Products
  Tips and Tricks on Diagramming
  
  
• Know more UML diagrams
  UML Diagrams

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