On 10/26/06, Alexandru Popescu <[EMAIL PROTECTED]> wrote:
On 10/26/06, Martin Cooper <[EMAIL PROTECTED]> wrote: > On 10/25/06, Wille Faler <[EMAIL PROTECTED]> wrote: > > > > Hi. > > I raised the question today on Don Browns blog about being able to have > > integration between Struts2 and DWR, to get a full MVC model if you only > > want to re-render a snippet of a web-page. > > I am not sure if this has been discussed previously, but Don encouraged > > me to send my ideas if I had any, so here goes: > > When I have done AJAX-based stuff, 9 times out of 10, all I really want > > to do i execute some business logic, and re-render a portion of a page. > > This would seem to fit well with a traditional MVC-approach, with the > > exception that I don't want to re-render the full page. > > > > Earlier this year, I implemented such a simple framework, basically > > using Webwork2/XWork and DWR, adding some code to glue it all together. > > It consists of the following things: > > - Some generic JavaScript that can interpret parameters (either from a > > form or URL) into a Map of parameters, akin to what Webwork uses. > > - A Controller that is called by DWR, taking the Map, a callback-target > > (in the web-page) and the name of an action as its arguments. This > > Controller then invokes an xwork ActionProxy to invoke the Action. > > - Custom Result-implementations for getting JSP-elements defined in the > > xwork results. These results use the DWR > > WebContextFactory.get().forwardToString() functionality, to get the > > resulting JSP-snippet as a String. > > - Said Result can then be sent back by the Controller through DWR, which > > is then handled by generic JavaScript and rendered to the predefined > > callback-target on the page. > > - When using forms, it can also do AJAX-based validation which makes use > > of proper Xwork-validation. > > > > As I said, I have already written code for this, it is quite compact and > > only a few hundred lines (11 implementation classes + generic JavaScript > > + dwr config), so obviously this integration is quite easy to create. > > > I'm not really a DWR user, but this seems like a lot of code to me, when all > you want to do is update part of the page. It pretty much depends on what you mean: "update part of the page". In case you want to take advantage of the whole MVC then I really think this is one of the right way to do it.
I guess I'm missing what you mean by "the whole MVC". Could you elaborate? In my example, I would be using the exact same MVC mechanism as I would use for a full page refresh. Nothing on the server side would be different. No extra code. Nothing.
If it were me, I would use Dojo > and simply make a single call to dojo.io.updateNode(node, url), with no custom code required on the server side. Not everybody is using Dojo, as not everybody is using DWR. Dojo is a heavy JS library, while DWR is a java library and from this perspective I think DWR has an advantage.
It is an unfortunate misconception that Dojo is "heavy". Dojo can be extremely lightweight if you only use what you need. If I need a pile of extra code on the server to use DWR, I'd say DWR is at a disadvantage. ;-) But I recognise that a lot of people seem to like it, and perhaps, as you suggest, because they're more comfortable using Java than learning JavaScript. And what is more important: there is no custom code on server side.
You just have your normal actions: you can invoke them through normal requests, but also thru AJAX.
But for some reason you need all that DWR-related code before you can get to your uncustomised code? This is the part that I don't get. It seems that the need for that extra code is solely because you are using DWR, which, in this scenario, you don't actually need. -- Martin Cooper
Can you help me understand what advantage I would gain by using DWR with this new code? > Simply said, and as the OP also mentioned: to use the same MVC paradigm with DWR AJAX invocation. HTH, ./alex -- .w( the_mindstorm )p. > -- > Martin Cooper > > > I > > would love to see something similar within the upcoming Struts2! > > I haven't attached the code to this mail, but it is available for > > download here: www.infonatural.com/ajax-mvc.zip (including > > jar-dependencies and some unit-tests, 3.6mb). > > > > If anyone wants to pick the code for ideas, or adapt it, feel free to do > > so as long as you retain the original @author comments as part of it (I > > am the sole copyright holder of the code, and you may use it under the > > ASF if you want). > > It would probably need some minor improvements to make it more in line > > with the rest of the Struts2-code (so tags work etc), as I only did the > > code originally for my needs and didn't bother doing more than I needed > > at the time. > > > > I apologise if this or something similar is already part of Struts2, but > > I got the impression that it may not be. > > > > regards > > Wille Faler > > > > > > --------------------------------------------------------------------- > > To unsubscribe, e-mail: [EMAIL PROTECTED] > > For additional commands, e-mail: [EMAIL PROTECTED] > > > > > > --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
