Getting slot id when launch

Hello!

I am developing my first max for live device, and I am stuck trying to do that my device recognise which midi slot is launched in the session view. Also I would like that it can tell what's the name of the midi clip launched. The device is placed in the same midi track, so I understand I have to start my patch with live.thisdevice patched with live.path this_device canonical parent, so it can identify the track where the device is sitting on. After that I am very confuse about how to use live.object and live.observer. I understand that with live.observer I can get the info of when the clip is launched? Is that right? I am not sure now what live.object could do :/ After I figure out that, the idea is that I will get the name of the empty midi clip launched and this will go to a node, and this will look for some movie clips files and play them in a jit.world window. That part I have it figure out, but launching and getting the information out of the launched slot is still difficult to understand.