I can't really do this since I eventually want to have the shipments list on both the 'Customer properties' and 'Order properties' pages - so that we actually have 3 views of the shipments:
- All shipments
- All shipments for a customer
- All shipments for an order (yes, orders can have multiple shipments).
However, I did try looking at the UIContext object on the Shipment_List.aspx page and have noted that when returning from the 'Shipment properties' (Shipment_Edit_General.aspx) page the ObjectID is 0. If navigating to the list from Customers or Orders then it does show the corresponding id although I'm also able to get this via the Query string which tells me whether its a customer or order as opposed to UIContext.ObjectId which doesn't pass the type.