Master view and auxiliary view

When you create a shape, it creates a model element as well as a view. We call the first view to be created from a model element a master view. For subsequent views created from the same model element, they are called auxiliary views. A model element can have unlimited number of auxiliary views. Yet, it can have at most one master view.

A master view differs from auxiliary view in that master view affects the parent assignment of the owned model element, while auxiliary view does not has such power. For example, if there is a pool with a task in it, and you try to drag the task out of the pool, the task's parent will be changed from pool to root. However, if the task is an auxiliary view, moving it to another parent will have the pool as its parent, remaining unchanged.

Converting an auxiliary view to master view

A model element can have multiple views. Yet, it can only have one master view. You can, however, convert an auxiliary view to become a master view. By doing so, the original master view will become auxiliary, and the assignment of parent element will be updated immediately base on the new master view when the conversion take place.

To convert an auxiliary view to master view, right click on the auxiliary view and select Selection > Set as Master View from the pop-up menu.

Converting an auxiliary view to master