Re: [Gwt-openlayers-devl] GWT-OpenLayers Showcase

[Edwin C. <com...@gm...>]

Hi Andrew,

Moving the code base down a directory as you suggest is definitely a
good idea! It was a mistake to have the src dir at the same level as
the showcase dir.

Better a long descriptive name (gwt-openlayers-showcase) than a short
name that is less descriptive :).

Are you taking the actual GWT showcase code as a skeleton? Is that
code free to use that way? The showcase makes use of generators,
aren't those generating stuff you are missing?

There are two things that would be nice to have, which are not in the
standard GWT showcase: 1) Tooltips over the tree items to provide a
short description of the example; 2) A search function for easily
looking up examples.

Interesting that you are using the Google/IO MVP solution. Is that the
solution that is explained on the GWT tutorial? I have been using
Ext-GWT's MVC, which I found very easy to use in practice and it seems
to require a lot less boilerplate code. The major thing I dislike
about using Ext-GWT's MVC is that logic ends up in classes that extend
Ext-GWT classes. However, it seems a bit painful excercise to tear
apart the View and the Presenter, as in the plain GWT solution. Do you
really benefit from that in practice? Acting upon the view appears to
be very tied to the view implementation. Also, the GWT solution seems
to be more abstract, leaving the developers to implement Presenters
and Views in their own ways (which may be a good or a bad thing). In
our apps the models are the data transfer objects, there are
controllers for each cluster of functionality (controllers register on
a dispatcher), and the controllers know about the different views,
which may update themselves in response to events dispatched by the
controller. They views have a method for creating the UI and methods
for acting upon it. The controllers contain stuff that you might want
to unit test. It does seem that it is easy to create an Ext-GWT like
MVC framework using HandlerManager, Handlers and adding simple
abstract View class.

Greetings,
Edwin

On 25 May 2010 01:42, Andrew Hughes <ahh...@gm...> wrote:
> Hi Edwin,
> The 2.1-M1 "MVP" *looks* to target developers on the google app engine who
> want a sping backend. We are using the Google I/O 2009 MVP solution - it's
> really really good! I'm trying hard to get the gwtshowcase working - but
> they have some classes that aren't released with the user or dev jars! I
> will probably raise this as an issue with GWT as I feel they are releasing
> reference/source code that won't work against any gwt releases.
> Do you think we can move the current code base down one directory?
> So that this gives...
> ./pom.xml (parent pom)
> ./gwt-openlayers (gwt-openlayers jar)
> ./gwt-openlayers-showcase (gwt-openlayers-showcase war) this is a long name
> but it is consistent with other things like the app engine url e.t.c.
> This will make it easier for me to get to work :)
> --AH
> On Tue, May 25, 2010 at 6:14 AM, Edwin Commandeur
> <com...@gm...> wrote:
>>
>> Hi Andrew,
>>
>> Couldn't find any good info on the new MVP either. I hoped it wasn't
>> the MVP they describe in the GWT tutorial
>> (http://code.google.com/webtoolkit/articles/mvp-architecture.html),
>> because I don't think that is a nice solution. I was more hoping that
>> they had a proper eventBus instead of hijacking HandlerManager for
>> that, and a little less convoluted solution.
>>
>> Greetings,
>> Edwin
>>
>> On 23 May 2010 12:49, Andrew Hughes <ahh...@gm...> wrote:
>> > Hi Edwin,
>> > Thanks heaps for your reply :)
>> > FYI:
>> > The 2.1-M1 MVP looks nothing like the existing "MVP Best Practices"
>> > we've
>> > seen come out of google. The only doco I can find is
>> > this http://blog.springsource.com/2010/05/19/spring-google-appengine/
>> > and it
>> > looks to me like it's about data retrieval from the server! Perhaps I am
>> > wrong, we will have to see.
>> > I'll try and update the showcase once I find out where the GWT missing
>> > classes are!
>> >
>> > Cheers.
>> > --AH
>> >
>> >
>> > On Sat, May 22, 2010 at 8:23 PM, Edwin Commandeur
>> > <com...@gm...> wrote:
>> >>
>> >> Hi Andrew,
>> >>
>> >> Great you are putting effort into the showcase. The showcase was put
>> >> together a long time back and with the new MVP framework in GWT 2.1 I
>> >> was thinking of trying that out, but you already have something going.
>> >> One thing I would also like to put in the showcase is a working 'show
>> >> source panel' that uses a syntax highlighting lib like
>> >> http://alexgorbatchev.com/wiki/SyntaxHighlighter
>> >>
>> >> As you know, the showcase was not setup as a Maven project, but as a
>> >> GWT Eclipse plugin project so it would easily run in Eclipse. Right
>> >> now you can just open it as an existing GWT Eclipse project, possibly
>> >> change the version of GWT your using and code away. However, I am a
>> >> big fan of Maven and would be in faovour of Maven if it can work in
>> >> such a way that is easy to run and debug the showcase using the GWT
>> >> development mode.
>> >>
>> >> Having the showcase in the cloud would be a big plus! +1 for that
>> >>
>> >> +1 for the zero-arg constructor (if Javadoc explains the how and why)
>> >>
>> >> RPC of geometry objects would be possible if
>> >> a) if we create a GeometryFactory which can take an OpenLayers
>> >> geometry, copy all the content to a GWT-OL geometry object
>> >>
>> >> b) if we create geometries that do not wrap Javascript objects, but
>> >> that are converted to OpeneLayers geometry objects when they are
>> >> provided as arguments to GWT-OL functions.
>> >>
>> >> Option b) would be very nice. We should investigate if we can use the
>> >> current objects and no longer let them extend OpenLayersObjectWrapper,
>> >> but let them be native GWT classes implementing IsSerializable (all
>> >> the implementations of the methods would change as well). Anywhere the
>> >> objects would then be provided to OpenLayers as arguments there should
>> >> be some GeometryConverter under the hood that copies all properties to
>> >> an OL geometry.
>> >> See also:
>> >>
>> >> http://code.google.com/webtoolkit/doc/latest/FAQ_Server.html#Does_the_GWT_RPC_system_support_the_use_of_java.io.Serializable
>> >>
>> >> Greetings,
>> >> Edwin
>> >>
>> >>
>> >> On 22 May 2010 10:26, Andrew Hughes <ahh...@gm...> wrote:
>> >> > Hi Edwin,
>> >> > I'd really like to do some work on the showcase. What I would like is
>> >> > too...
>> >> >
>> >> > Take the GWT Showcase application source and replace their examples
>> >> > with
>> >> > ours
>> >> >
>> >> >
>> >> > (see http://ongwt.googlecode.com/svn/trunk/com.google.gwt.sample.showcase.Showcase/Showcase.html)
>> >> > I'm close to getting this working but the (compile time annotations
>> >> > for
>> >> > the
>> >> > generators are relying on gwt classes that aren't in the OEM jars -
>> >> > should
>> >> > be able to get this working soon enough).
>> >> > Deploy the GWT-OpenLayers Showcase to the google app engine. I took
>> >> > the
>> >> > liberty of registering "gwt-openlayers" (and I need to find out how I
>> >> > can
>> >> > share this with you).
>> >> > Populate the showcase with examples....
>> >> >
>> >> > This might be just me but I really do feel this should also be a
>> >> > maven
>> >> > module. I find it very difficult to work with the showcase project in
>> >> > it's
>> >> > current state.
>> >> > Just a few other things...
>> >> > We need client/server rpc serialization of geometry objects. I know
>> >> > you
>> >> > said
>> >> > you had been working on this, any chance I could see how you're
>> >> > trying
>> >> > todo
>> >> > this?
>> >> > We use the UiBinder heaps in our app, the way it applies styles and
>> >> > layout
>> >> > means that the MapWidget should offer a zero arg default constructor.
>> >> > I
>> >> > don't believe there is any requirements from OpenLayers for width and
>> >> > height
>> >> > on init. I think a zero arg constructor might be a good idea (I do
>> >> > have
>> >> > a
>> >> > workaround)
>> >> > Cheers.
>> >
>> >
>
>