Public bug reported:

When a ListItem is dragged, it emits "Started" and "Moving" events.  But
if each "Moving" event is accepted, as happens in a live drag case, no
"Dropped" event will be emitted when the item is finally dropped.  One
should be added.  The "to" and "from" parameters could both be set to
the final position, or they could be set to an invalid value.

Example use cases:
1) Updating an underlying data store.  The QML list model may present data 
stored on disk.  (In a database, for instance.)  Updating the model may be 
quick while updating the disk store is slow.  It would be nice to be able to 
give the feedback of the live updates but put off updating the data store until 
the drag is over.  The "Dropped" signal is necessary for this.
2) Changing styling during drag.  A developer may want to change some styling 
of elements other than the dragged element during the drag.  For instance, 
non-dragged items could be shaded so as to be less prominent, or additional 
information could be presented.  The "Dropped" signal is necessary to know when 
to reset the styles.
3) Consistency in a mixed drag action.  By choosing which "Moving" events to 
accept, a developer can create a situation in which parts of a drag are live 
and others are not.  Currently, the "Dropped" signal will be emitted for some 
of these drags and not for others.  In addition to being surprising, this may 
complicated clean-up code.  If the "Dropped" signal is always emitted, this 
situation would be simplified.

** Affects: ubuntu-ui-toolkit (Ubuntu)
     Importance: Undecided
         Status: New

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https://bugs.launchpad.net/bugs/1500118

Title:
  ListItem feature request: Signal at end of live drag

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