This is where I diverged from the typical MVP pattern, the Has*
interfaces just became to numerous and unwieldy. My solution was to
make the
"model" richer, and attach a Map of "state values" to each model
property. It was then up to the Presenter to interpret the associated
property state map, and display accordingly.

At first, I had general "model change listeners" drive the UI. I
wanted to convert to GWT 1.6+ custom events and event handlers(bus),
but these grew too numerous also.... still looking for a concise
solution.


On Aug 19, 8:49 pm, Davis Ford <[email protected]> wrote:
> You and others have won me over, Ian :)
>
> I re-factored to all interfaces.  One of my biggest pain points was
> the crazy number of mock and mock returns I was ending up needing --
> that, and I needed to included gwt-dev on the classpath, which the
> codehaus gwt-maven-plugin warns not to do...
>
> It still blows up kind of big when you have a form with even a
> reasonable number of widgets on it.  Example, I have 7 text boxes on
> one form.  For each, I want to get at its value and also set a blur
> handler...so I end up with:
>
> interface Display {
>    HasValue<String> foo();
>    HasBlurHandlers fooBlur();
>    ...
>
> }
>
> That leads to 14 methods in the interface -- I wish there was some way
> to collapse this.  I also have 7-8 additional HasClickHandlers, and a
> number of methods like:
>
> void displayFooError(boolean toggle, String msg);
>
> To tell the view to report an error.  So in the end, the interface for
> *this* particular presenter is fairly large, but so be it, I guess.
>
> Sorry, to hear your project got hi-jacked.  I enjoy your blog posts --
> hope you will keep posting stuff on GWT.
>
> Regards,
> Davis
>
>
>
>
>
> On Wed, Aug 19, 2009 at 7:15 PM, Ian Bambury<[email protected]> wrote:
> > My feeling is that, if you design things properly, you will not need to end
> > up with a bloated interface.
> > For example, in a registration page, you don't need to have something for
> > every field if you require name/address/phone number, you just link in to
> > HasInternationalContactDetails and that widget deals with all the associated
> > problems. You just set it up with hicd.emailRequired(true) and
> > hicd.phoneRequired(false) and so on. That widget then knows how to set
> > itself up. If you need to insert current details, you use
> > hicd.displayDetails(userContactDetails).
> > You check everything is OK with if(!hicd.isValid())hicd.displayErrors();
> > You get the user contact details back with hicd.getContactDetails();
> > All you need in your interface is HasInternationalContactDetails
> > getContactDetails();
> > Everything else works from that interface, not yours.
> > Whatever it is that conforms to that knows all about zip and postal codes
> > and what to validation apply (because it probably has a country dropdown and
> > can use that) same with phone formats.
> > The HasInternationalContactDetails widget itself uses other widgets (like
> > phone number) which can be used elsewhere if needed but at the very minimum
> > break the functionality into manageable units.
> > I'd love to give this a try, but unfortunately my current project manager
> > (and funder rolled into one) seems to have just dropped GWT in favour of
> > Zend and the 'here's an idea for a screenshot, make it work' approach to
> > system design.
> > Sigh!
> > Ian
>
> >http://examples.roughian.com
>
> > 2009/8/19 davis <[email protected]>
>
> >> Point taken Ian.  I think the design tradeoffs are at least on the
> >> table.  In most cases, I think I'm comfortable with coupling the view<-
> >> >presenter in a 1:1 relationship -- (i.e. not making universally
> >> generic presenters that can be used with any view), but I understand
> >> your argument, and can see the need for this in some scenarios.
>
> >> On Aug 19, 8:30 am, Ian Bambury <[email protected]> wrote:
> >> > 2009/8/19 Davis Ford <[email protected]>
>
> >> > > My basic question is: why not just return TextBox if that is what is
> >> > > in your view?  The coupling is between 2 classes: view and presenter.
> >> > > If you later change TextBox to SuperWidgetTextBox, you can re-factor
> >> > > it in your IDE in 5 seconds and be done with it.
>
> >> > > Am I missing something?
>
> >> > If that is the way you want to go then fine.
>
> >> > What you might be missing is that some of your views may not be using
> >> > text
> >> > boxes. One view may be using a text box. Another might use a label,
> >> > another
> >> > might use a button, or a text area, or a hyperlink, or a menu item. They
> >> > can
> >> > all display text.
>
> >> > An on/off indicator and a switch are just a boolean and something
> >> > clickable,
> >> > but you don't decide in the presenter that is should be the words 'on'
> >> > and
> >> > 'off' and demand a label, you leave it as boolean and let the view
> >> > decide
> >> > whether to put yes/no, on/off, true/false, a checkbox, an image of a
> >> > lightbulb on and off, etc - and the clickable thing could be a button
> >> > with
> >> > those words, or a picture of a switch, or the checkbox.
>
> >> > The presenter can be used for all these views. Different views can
> >> > register
> >> > with the same presenter. Users can choose their preferred view and swap
> >> > views in and out.
>
> >> > Ian
>
> >> >http://examples.roughian.com
>
> --
> Zeno Consulting, Inc.
> home:http://www.zenoconsulting.biz
> blog:http://zenoconsulting.wikidot.com
> p: 248.894.4922
> f: 313.884.2977
--~--~---------~--~----~------------~-------~--~----~
You received this message because you are subscribed to the Google Groups 
"Google Web Toolkit" group.
To post to this group, send email to [email protected]
To unsubscribe from this group, send email to 
[email protected]
For more options, visit this group at 
http://groups.google.com/group/google-web-toolkit?hl=en
-~----------~----~----~----~------~----~------~--~---

Reply via email to