project tree watcher interface plan

[dukju ahn]

> > You misunderstand. I ask why each manager requires it's own file watcher
> > class, when it's not needed. Handling these FS notifications can be done in a
> > build manager specific way with just signals and slots , or by having the
> > build manager implement an interface. Or even better, just have the build
> > manager do its own thing with regard to file system watching.
> >
> > IMHO, after thinking about it more, this is not a problem that requires a
> > platform based solution.
>
> I object - partly. While I do agree that having a file watcher on each
> manager or each project is not needed I think its good to have a
> directory watcher in a central place so that the managers are not
> required to re-invent the wheel here. I don't have a patch at hand, but
> I'm thinking of something like a QFSWatcher inside the projectcontroller
> and the controller sends out signals for new or removed files (or calls
> the manager slots directly).

Please note that  the main feature of suggested class is that it stores
Project**Items in hash table when we call QFSWatcher::addPath().
So that when we get filesystem notification,  we can easily retrieve
corresponding Project**Items.
Just having a general watcher is insufficient. One of the goal is to
synchronize Project**Items with actual disk file.