Create controls dynamically in schematic

Hi folks,

I'm a newbie to these forums!

Here's my problem: I'd like to create a schematic by giving the user a box of items (say circuit elements) that the user can drag and drop into place. The user could then set a property of the element, such as a COM port, and then a polling machine (separate) would say retrieve a value and display it in an indicator associated with the element.

I understand how to poll, say in modbus, and I understand event structures although I've only ever used them to detect a front panel click per the producer/consumer with events pattern. Any help in how to create a new control on the fly, as well as how to refer to it in order to update it regularly say, as well as how to drag and drop it, would be really appreciated!

Thanks,

Rik