Develop environment-focused Add-In

[Maxim-CADman77]

I'd like to know how to turn my Add-In to "focused"* on given environment (ex. -Part 3D-model)?

*
I mean Add-In should auto-unload if no documents open or active document type differs from the given.
Inventor does have built-in "focused" Add-Ins, here are several examples:
Assembly Bonus Tools - Assemblies (3D)
Design Accelerator - Parts (3D)
Drag & Drop Interoperability - Parts (3D)
ESKD Support - Drawings

[tyler.warner]

You can add buttons to the ribbon specifically for those environments (part, assembly, drawing, etc.) & tie commands to those buttons which are associated with the given environment. Would that work for what you're looking for?

[Maxim-CADman77]

The question is not about where to add buttons..

[nmunro · Accepted solution]

You can control add-ins in a couple of ways. In your .addin file for the add-in you can include a <LoadBehavior> flag that controls when the add-in first loads.

LoadBehavior - (Optional) Specifies when the add-in should be loaded in Inventor. This is important for better startup performance. This option can be specified using one of the following values:

0 - Load immediately on startup (not recommended)
1 - Load when any document is opened
1 - Load when a part document is opened (same as previous)
2 - Load when an assembly document is opened
3 - Load when a presentation document is opened
4 - Load when a drawing document is opened
10 - Load only on demand, either through the API or using the Add-In Manager.

Once loaded you can activate / deactivate individual add-ins using the ApplicationAddIns collection (property of the Application object) and checking to see if your ApplciationAddn object is included in the collection. Do a search on these properties in the Developer help for more information.