From iOS 10 onwards apple have introduced the addAndSetupAccessoriesWithCompletionHandler method to add the HMAccessories to the home. In this method ^(NSError *error block is executing when we successfully add/cancel the accessory setup.
But my question is I would like to know when this viewController is presented? For reference I have attached the image. Thank you so much for your valuable time. Any ideas/suggestions will be appreciate.
You may take a look first on HomeKitDeveloperGuide, do you may use a trigger ?