Yes, creating an object graph for Vaadin or Wicket should certainly be doable based on XML definitions of screens and forms. You could even have scriptlets for additional screen functionality in the platform-specific (or in Moqui render-mode) element.
And interesting approach for this might be to create a Groovy script based on the screen/form XML files, much like the Moqui XML Actions template does. That template just uses FreeMarker Macros to create a script based on the XML (which makes it easy and computationally cheap to have Groovy expressions and scriptlets scattered about the XML), and that script is compiled using Groovy to a class which is cached for use (all at run-time). This would make an interesting add-on to Moqui, if anyone is interested. I've added a section on creating add-on components to the Introduction to Moqui Framework document (http://sourceforge.net/projects/moqui/files/), and there is now a page on the Moqui site to list add-on components (pretty empty right now... ;) ) at: http://www.moqui.org/crust.html One thing I wonder about using the Vaadin/Wicket approach and the OFBiz/Moqui approach together is how much value it would add to create Vaadin/Wicket screens from XML screen/form definitions. In other words, would it be easier to develop Vaadin/Wicket screen using their native Java code directly, or through an XML screen/form definition? On the other side of the coin, would the resulting UI for XML screens/forms be better based on Vaadin/Wicket than on plain old HTML, CSS, and jQuery? Before trying it out it may be hard to tell... or in other words only by trying it in a few scenarios would make answers to those questions clear. -David On Apr 8, 2011, at 8:39 AM, Ean Schuessler wrote: > > To me the convenience is being able to program to a straight AWT like > interface. It is just so convenient to be able to do things like: > > > > myButton = new Button("Click Me", new Button.ClickListener() { > public void buttonClick(ClickEvent event) { > myLabel.setValue("You clicked my button"); // simple stuff like this > dispatcher.runSync("SetPartyRole", [roleTypeId: 'BUTTON_CLICKER']); // or > even things like this > } > }); > > > The process of binding these events to URLs to trigger services and worrying > through AJAX processing just falls away. I could add a dozen buttons to a > page and concentrate on the logic they trigger instead of a pile of oddly > named events and url bindings. Sure there is some memory overhead there, sure > it has state but man does it make some things easier. > > > I think your answer (as I've illustrated above) makes perfect sense and you > can definitely just trigger a service engine from these other frameworks. > However, I've wondered for a while why we couldn't construct stateful graphs > of UI objects from the XML widget descriptors and have the event bindings > attach directly to the widgets. > ----- "David E Jones" wrote: >> That's a tough one. I just did some research on Vaadin, and in some ways it >> looks similar to Wicket, and I suppose in some ways similar to JSF as well, >> though Vaadin appears to be a sort of extension to GWT and the unlike Wicket >> where the Java code is mostly run on the server (if I understand right) in >> Vaadin most of the Java code is transformed using GWT and run on the client, >> turning the client into almost a desktop app that communicates with the >> server to mostly pass data around. >> How to get any two technologies like these to work together is a good >> question, or at least how to get them to work together seamlessly. Say you >> want to write part of your app in Vaadin and part of it in Wicket... how >> will you get them to work together well? I think the answer is that you >> could have them both deployed in the same webapp, and pages written in each >> could link to each other, but sharing decoration (except by including the >> same text or using a tool to interpret a template that they can both >> include) and navigation and such would be a nightmare. >> In Moqui, like in OFBiz, most of the web UI stuff is based on writing to a >> writer or stream and being able to assemble various pieces of text to create >> a single web page. Without getting into lower level code, I looked at each >> of these three (Vaadin, JSF, and Wicket) and it does not look like they have >> a way to generate text to be included in a web page, and perhaps worse >> handling navigation and links is so ingrained in the way the tools are >> designed that nothing there could be shared (not in ways that I could find, >> though of course with enough creative coding anything could be done in >> theory). >> So, I guess the answer is that just like with OFBiz, with Moqui Framework if >> you want to use one of those web UI frameworks then use that instead of the >> Moqui XML Screens/Forms, and just use other parts of the Moqui API through >> the ExecutionContext that could be inited/destroyed in an event listener >> instead of the MoquiServlet (since the MoquiServlet wouldn't be used in that >> case), or if desperate you could use the Moqui class for static init of the >> ExecutionContextFactory and ExecutionContext. >> That parts easy, ie use Moqui API for services, entities, and other tools >> but not for the web UI... trying to merge and share artifacts between these >> kinds of restrictive UI approaches would be tough. On the other hand, if you >> can get plain text out of them, you can include that in any Moqui XML >> Screen. >> I don't think a better solution to this exists. Personally, I blame JSP and >> their restrictive nature that has been considered acceptable over the years, >> and those sorts of restrictions now seem to bleed into all sorts of web UI >> frameworks. > > -- > Ean Schuessler, CTO > [email protected] > 214-720-0700 x 315 > Brainfood, Inc. > http://www.brainfood.com
