devicenotifier with qgw

[Jacopo De Simoi]

Dear Plasma-devs
  Giulio and I are currently porting the device notifier to use qgw, the delegate stuff was really too rigid to implement decent animations and a few features (e.g. busy widget on top of the item being (un)mounted). 
Of course we'd like to use the shiny new itemBackground; I'd like to ask you guys what  do you think about the following modifications:

1) we need to activate the items on hover, but with the itemBackground animation delay, hoverEvent is not good anymore to track that. I can see two solutons:
    -  itemBackground should send some signal when its animation finishes, something like targetReached(qgi *) where the pointer would be null if the target was not an item. 
    -  itemBackground should make publicly available the animation time, so that we can animate accordingly fadein/fadeout in each item. 

2) we need a way to destroy the hover when the mouse leaves all items; i propose this solution:
    - implement a method ItemBackground::hideRequest (qgi* item) which does the following: if (current target != item) return; else trigger a singleshot which would in turn trigger a setTarget(0) unless setTarget is called in the meantime.

What do you think about that?
Thanks

  Jacopo