Tell host that the Plug-in controller changed a program list (rename, load, PitchName changes). \param listId is the specified program list ID to inform. \param programIndex : when kAllProgramInvalid, all program information is invalid, otherwise only the program of given index.
Notify host when a module is selected in Plug-in GUI.
Host callback for unit support. \ingroup vstIHost vst300 - [host imp] - [extends IComponentHandler] - [released: 3.0.0]
Host callback interface, used with IUnitInfo. Retrieve via queryInterface from IComponentHandler.
\see \ref vst3Units, IUnitInfo