Re: Easiest way to build Qt/Gtk interfaces for Ada programs

["Yannick Duchêne (Hibou57)" <yannick_duchene@yahoo.fr>]

Le Sat, 29 Dec 2012 13:27:56 +0100, Dmitry A. Kazakov  
<mailbox@dmitry-kazakov.de> a écrit:
>>> You have to design all
>>> vital data structures as models compatible to the GUI framework at
>>> hand.
>> You may do this way, while you are as much free to adapt the UI to an UI
>> specification, a specification which specify a human interface to a
>> computation or service interface.
>
> No way. If you have, say, a DB and want to show its contents in a list
> control, the DB client must be a list store (the model deployed by the  
> list
> control). If the DB client was designed in a way that does not support
> delivery of the result set incrementally, in portions, the UI will block
> when rendering large result sets. If the DB client delivers each row
> separately, that will choke the UI with a flood of events etc. You can do
> nothing about it. You have to change the client [or write new list  
> widget].
The presenter can handle this. Or else, a specific widget is an option  
too, indeed.

>>> You have to place inspection/rollback/abort check points in all
>>> lengthy operations to be able to add progress bars, cancel buttons etc.
>> You may, if you designed the application. But you may as much have to  
>> add
>> an interface to an already existing application which does not provide
>> these facilities.
>
> It is very simple to [dis]prove your theory. Take (RM G.3.1)
>
> function Solve (A : Real_Matrix; X : Real_Vector) return Real_Vector;
>
> The objective is to start it on a button click, show a modeless dialog  
> with
> a progress bar and a cancel button inside.
That is going too far.

>> Also, may be there's some confusions between application interface and
>> user interface in this topic (some comments make me feel that; see  
>> above).
>
> Oh, yes. Fancy papers about GUI design consider UI the problem space.  
> They
> already took for granted that applications are built around the GUI. And
> all GUI frameworks I know require no less.
These are two problem spaces, and none of both is at the centre (that's  
why it may suggest mediation).


Have an happy day


-- 
“Syntactic sugar causes cancer of the semi-colons.” [1]
“Structured Programming supports the law of the excluded muddle.” [1]
[1]: Epigrams on Programming — Alan J. — P. Yale University