Re: UI-update

On 11/29/2011 02:48 AM, Troels Sørensen wrote:
> I don't think that the active layer should have any influence on what
> can be deleted.  Imagine your text-editor saying "You cannot delete this
> line; that's where your cursor is".  There are two situations to
> consider here:
> 1) The layer to be deleted is active in the current view: the user
> already has focus on the layer-frame, and can see what is going on.
> 2) The layer to be deleted is active in another view: the user has to
> change to that view for it to even matter.  It seems unlikely that the
> user will remember what layer was active on that view, but not be able
> to remember that it was deleted.

You make it sound as if the active layer was of no consequence.  Of 
course the user shouldn't need to remember it - that's what we have the 
computer for.  But users expect that when they return to a view later 
and add material to it, it will appear at the right spot in the view 
sequence.  If you silently change the active layer, you break this behavior.

I don't see any situation where a user would willingly delete a layer 
that is active in another view unless they actually intended to delete 
that view at the same time.  So Ipe could ask "Layer 'beta' is the 
active layer of view 3, do you wish to delete this view?" - but I doubt 
anybody would really want to answer "Yes" to this.  The natural response 
would be to go to view 3 and double-check.  So I think just showing the 
message "Layer 'beta' is the active layer of view 3 and cannot be 
deleted" is sufficient.

Cheers,
  Otfried