Peter, Thanks for your response.
The reason why I wanted to dynamically load a component was because I need to preload list pages for certain entities in my application. So I have a certain "central" page that the user loads once and these list pages need to be cached on the browser, but I sometimes override the list pages (similar to how Tynamo allows customizing pages). Ideally I'd have some sort of Javascript stack (as in T5.2) that allows me to call a generic list page or an entity specific list page (if it exists) and then cache it on the browser side. Actually, the javascript stacks in T5.2 are perfect for what I am looking to do, the only problem is that they work off of Assets only and I have no way of combining scripts that certain pages generate (I have pages that generate javascript only). So maybe that is another way to approach it, is there any way to get a similar result as the Javascript stacks that work off of pages instead of Assets? I hope all of this makes sense... Cheers, Omar On Tue, 5 Oct 2010 11:50:05 +0000 (GMT), [email protected] wrote: > Hi Omar, > >> I am trying to dynamically load a component which must be determined at >> run time > Do you need to define the component at runtime, or simply choose the > component at runtime? For most cases, and I suspect yours too, all you need > to do is choose from a number of existing components, if so then it is > possible to do exactly what you require, but with a different approach. > > If you get your head around how composition works in Tapestry then its not > so daunting. Blocks don't need to be defined in any particular order, they > can be reused any number of times and precise rendering can be controlled. > The solution I used was to create an 'assembly component' that assembles > components via a tree, it works great and eliminates all those if / else's. > > > But for any solution consider that somewhere you need to define > components, and somehow choose them, whatever approach you use, you can't > really escape this, so why not do this all in the same place? If you > require recursion then do it in Java and assemble a tree to iterate over in > your UI. Its not very much more work, just a different approach that also > has the advantage that most of the core logic is done in Java so can be > examined with a debugger. If you need more control over rendering then use > the HeartBeat Environmental service, though I don't know of many good > examples. > > cheers, > Peter > > > > ----- Original Message ----- > From: "Omar Carvajal" <[email protected]> > To: "Tapestry users" <[email protected]> > Sent: Tuesday, 5 October, 2010 07:19:27 GMT +02:00 Athens, Beirut, > Bucharest, Istanbul > Subject: Re: Dynamically loading a component > > This is horrible news since I have no way of knowing the components that > needs to be called at design time (other wise I would use a <t:block>). > > There is no magic that can be done to achieve this at all? Even if I have > to use the internal services. > > Thanks for your quick response. > > Omar > > On Oct 4, 2010, at 18:41, "Thiago H. de Paula Figueiredo" > <[email protected]> wrote: > >> On Mon, 04 Oct 2010 19:35:38 -0300, Omar Carvajal >> <[email protected]> wrote: >> >>> Hey all, >> >> Hi! >> >>> I am trying to dynamically load a component which must be determined at >>> run time, I figured I must use a t:delegate to render the component. >>> On the Java side of things I cannot figure out how to instantiate the >>> actual component. I saw the @Component annotation with the "type" >>> parameter but this does not let me dynamically load a component from a >>> function. >>> Does anybody have any idea on how to do this? >> >> Declare the components inside a <t:block>. <t:block> are not rendered >> unless you pass it to a Delegate or return it to update a Zone. You >> cannot instantiate components in Java code, as Tapestry is static >> structure, dynamic behavior (including rendering). Take a look at >> http://tapestry.apache.org/tapestry5.1/cookbook/switch.html. It shows you >> how to render blocks dynamically, but the same approach can be used for >> components as well. You'll use @InjectComponent to get access in your >> Java code to the component instances declared in templates. >> >> -- >> Thiago H. de Paula Figueiredo >> Independent Java, Apache Tapestry 5 and Hibernate consultant, developer, >> and instructor >> Owner, Ars Machina Tecnologia da Informação Ltda. >> http://www.arsmachina.com.br >> >> --------------------------------------------------------------------- >> 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] > > > --------------------------------------------------------------------- > 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]
