[news.eclipse.platform] Re: [Databinding, General UI] UI brainstorming,

[Tom Schindl <tom.schindl@xxxxxxxxxxxxxxx>]

Boris Bokowski schrieb:
> We had a good discussion on the topic of using modeling for UIs at the 
> Eclipse Summit Europe 08. What I took away from that discussion is that 
> there are three areas where modeling makes sense:
> 
> 1. At the widget level, where you would have a 1:1 mapping between the 
> widgets and objects in your model. XSWT and XWT are in this space, as is 
> Olivier's wazaabi 2. What I find important is that at runtime, you don't end 
> up with twice as many objects, so being able to directly create widgets from 
> a persistent representation is important. At the same time, having EMF 
> objects that are again 1:1 mapped to SWT widgets is interesting for tooling 
> purposes, so maybe what we should do is have a persistent format for SWT 
> widgets, which can also be read in to create EMF objects if you are in 
> "design mode".

Well this is where we both disagree. I take the point that it doesn't
really matter if those objects stay in memory. On the other hand say if
an Ecore-Model backing up the UI stays in memory you could generate some
benefits like you'd have to code your own:

- XPath like querying out of box to find Widgets
  (UFaceKit by the way provides such a feature this we are going to use
   this for our binding story)

  I think here along the following lines (I just made up this syntax so
  please don't blame me):

  ui.xml:
  -------
  <window>
    <label text="City" />
    <text />
  </window>

  bind.xml
  --------
  <bindings>
    <bind-value
      widget="/window/text[0]/@text"
      value="/city/@name" />
  </bindings>


- Easy-Client-Server split

  Server-Model <=> Client-Model <=> Widget-Toolkit
             Network            JVM
- ...

This allows to optimize the client-server traffic without the need to
hand-craft a protocol.

I still believe that a medium sized RCP-Application is not built of so
many widgets that you'll notice it. If you think about CDO which has
quite smart logic to wipe unreferenced model-objects this gets an even
smaller problem. Where I agree with you is that this should be an opt-in
model so I should be able to decide myself whether I want a Live-Model
or not but I would not limit it on design mode.

Tom

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Tom Schindl                                          JFace-Committer
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