[Uml-devel] u2 user interface

[Andrew Sutton]

On Monday 24 March 2003 5:32 pm, Sebastian Stein wrote:
> Andrew Sutton <ansutton at kent.edu> [030324 19:55]:
> > so. any feedback on that? otherwise, that's probably the direction i'm
> > dragging this thing.
>
> I don't like tree views very much. I think they get very complicated if you
> have more then 3 levels.

2, i think. the main window (or at least the split with the outlook bar - also 
apparently called a listbar or sidebar) is intended for view management. i 
can't imagine having so many views that we need to get really complicated.

> Let's say there is a "Use Case" button in the bar. You click on it. The
> main widget changes. What do you expect to see? I think a list of all
> objects related to the use case view would be logic. So a list with all:

the contents of these views are yet to be determined. if we accept that a view 
contains a collection of documents (i.e, diagrams) then we should be looking 
for an appropriate document management view. i have one in mind ;) there's a 
little project called photomesa that provides the impetus for the view. of 
course, we'll see what happens with that.

i suspect however, that in the new view (the use case view) the window will be 
split. the left half will contain a tree view (focused on the use case 
package) and the right will contain something else.

> Clicking on a acteur, use case or association object would result in the
> property window to be shown.

maybe a dialog. i don't think we should populate the view with that 
information.

> Clicking the use case diagram would remove the list and show the diagram.

that sounds reasonable to me. this is the way umbrello works now - except for 
removing the tree view. that should stay.

> You could provide a back and forward button in the toolbar to get back to
> the list from the diagram. (something like in a browser)

yes. because we have a concept of navigating between views, a browser history 
(including back and forward) would be useful.

> I think this could work well, but only if you have not more then 3
> information levels.

with pure uml we only have 3 types of views.
1. the 4+1 - this constitutes the top level and is the equivilant of the 
outlook bar.
2. abstract views (logical view, process view, etc) - basically views that 
focus on top level packages of a model
3. diagrams - theoretically contained by packages

> Maybe there could be a completly other approach. I mean in structured
> analysis you first draw a context diagram. Then you can zoom in and get
> data flow diagrams. Clicking on a function could show another DFD or the
> actual code. You could go deeper and deeper. Clicking on a storage could
> result in getting in a ERM.

that's an issue of linking and something i definitely think we should address. 
i believe that would be called a "drill down" operation. the real question is 
how we can take standard UML (or modified) and make it work like that. i 
don't want to rule it out because its a very powerful technique.

> Maybe there is something like this in UML. Couldn't we identify a top level
> view of the whole system? And than providing navigation to get deeper into
> the system?

nope ;) at least not that i'm aware of.

> If I'm right, I think the UML model is just like a cube. You can have
> different views on this cube by rotating it. You can zoom in and zoom out
> and make slices. So it is only a question of navigation.

interesting analogy. i would certainly agree that there are different 
dimensions to UML. in fact if you look at all the facets they satisfy 
notations for all 5 of the 4+1 views. if you consider each of the 4+1 views 
to be a slice, then we need to really think about how we represent each 
slice.

> I'm not sure how to do it at all. But please (to all) give some input,
> because it is a very important point at the moment. And please don't start
> codeing now...

no fear. i'm doing research on existing techniques for this right now. 
interestingly, there's never been any research like this. people may talk 
about UML diagram layout, but not visualization environments.

andy