RFC: disabled (or not yet enabled) collections in the browser

[Bart Cerneels]

I want to make it possible to list a collection in the CB but not
actually enable it until the user has clicked on the collection root
item.

Use case for this:

- UMS Collection is not scanned by default (huge resource drain). It's
already listed in the CB but without tracks until the "Scan device"
action is triggered. That action is only shown if the mouse is over
the root item because it would cause to much visual clutter if always
visible. As long as the collection is not enabled though there is no
byline text either.
If the root item would show "click to start scanning" it would be a
lot easier to use for novice users already.

- Nikhil's UPnP collection also needs to scan if the mediaserver does
not support Search. This "directory-walking" uses network, CPU and
memory resources in a serious intensive way. If a couple, or one very
large, search-less UPnP mediaservers are on the network, this could
bring amarok to it's knees. The user will click servers that really
should be scanned.


Currently the byline (text underneath the collection's name) is
hardcoded to show track count. I would like to change this to show a
different text when the collection is disabled and trigger some action
when the item is clicked.

I plan to add a state to Collection and use it in the browser with a
hardcoded string. When state == disabled some function will be
triggered to enable a collection ( perhaps re-using
startIncrementalScan() ).

Does anyone have a different use case that requires a custom byline?
Perhaps we should not hardcode any of the bylines.

Bart