Actual example how to integrate a plugin into UI

Hi! I find good and actual example how to integrated openapi plugin into Visual Paradigm UI. Most examples are outdated or not complete.

Good example should include:

  1. Add a custom ribbon panel (My Plugin)
  2. Add a menu to existing menu (I found how to do it here plugin.xml · master · Lukáš Ondrák / Master Thesis - Text Format Diagrams · GitLab)
  3. Add an item to a context submenu (for example, an item into Export after Save as xml…)
  4. Add custom submenu into context menu (for example, My Plugin/Action1, My Plugin/Action2)

Can anybody help me?