When your project is simple, you are able to express all of the design ideas with just a few diagrams. The diagrams are simple and self-explanatory. Each of them represents a distinct design idea and there is no overlapping between diagrams.
When you are dealing with a complex project, you may need to draw multiple diagrams to represent different contexts. You need to borrow shapes from a diagram to make them appear in other diagrams (i.e. contexts). In fact, this is extremely common when modeling with class diagram and business process diagram. Take UML class diagram as an example, there may be a domain diagram that presents all the entity classes and another diagram that presents the associations and dependencies between a specific controller class and its related entity classes. So in this case, both diagrams contain the same set of entity classes.
Instead of re-creating those classes again and again in different diagrams, Visual Paradigm allows you to “re-use” them. Through simple copy and paste (Ctrl-C and Ctrl-V), you can easily copy a shape from one diagram to another. Each shape is formally known as a “view”. So with this, you can create multiple views for a model element in representing different contexts. Changes made on a shape are all synchronized to other instances that appear in other diagrams without extra effort. This is great but there is a drawback though.
A master view is simply the specific view of model element that decides the placement of that model element within a model hierarchy. When you draw a shape on a diagram without reusing an existing one, the created view will be treated as the master. Subsequent views are all known as auxiliary views. When you attempt to move a master view to another parent shape, you are updating the real model structure as well (as reflected in Model Structure View). However, when you move any auxiliary view to a different parent shape, there will be no change at all on the model structure.
Selecting a master view
A model element can have multiple views. Yet, it can only have one master view. You can change the master view of a model element. By doing so, the original master view will become auxiliary and the assignment of parent element will be updated immediately based on the new master view.
- Open the Show Views window first. In Model Structure View, you can open it by right clicking on the target model element and selecting Show View… from the popup menu. In diagram, you can open it by right clicking on the target view and selecting Related Elements > Show Other Views… from the popup menu.
- In the window you can see a list of views of the selected model element/view. Click Set Master View…at bottom left corner.
- This shows the Set Master View window. You can select on the left hand side the Model Explorer or a specific diagram to be the master view of selected element. To select Model Explorer means that any re-positioning made in views in any diagram will not affect the model hierarchy. Click OK to confirm your selection.