Mirroring model element
Referenced elements are read-only when being presented in current project, which is good to avoid changes being made unexpectedly on referenced elements. However, it can be trouble-some when the referenced elements are in container type, such as a package or a pool (BPMN). This is because when you are referencing a container-typed element, you probably want to add things into it. In order to support this need, Visual Paradigm supported the concept of 'mirror'. By mirroring a model element from referenced project, that element will be localized partially by keeping a mirrored copy in your project which echoes the element in referenced project. The mirrored copy is still non editable except that you can add elements into it.
When you visualize a referenced container-typed element in your project, that view is not yet mirrored. When you try to add a shape into it say by drawing one inside or by dragging one into it, the referenced container will be converted into a mirror automatically. If you want to convert a referenced container into a mirror manually you can right on it and select Convert to Mirror from the popup menu.
The following resources may help you to learn more about the topic discussed in this page.
|2. Referencing other projects' model elements||Table of Contents||4. Viewing referenced diagrams|