In Tapestry 4.0, you could easily override the
tapestry.url.LinkFactory service for this purpose.
On 5/12/05, Robert Zeigler <[EMAIL PROTECTED]> wrote:
> Question: why not just specify your custom renderer to the page link
> component?
>
> <a jwcid="@PageLink" page="somePage"
> renderer="ognl:defaultLinkRenderer">Some Link</a>
>
> You could wrap the page link component in your own custom component,
> specify the renderer in your custom component, and then just you your
> AppPageLink (or whatever you decide to call it) throughout your
> application. :)
>
> Robert
>
> Preston L. Bannister wrote:
> > Preston L. Bannister wrote:
> >
> >>>>> I have a web application (to be implemented using Tapestry) that
> >>>>> will be called from another web application with a single
> >>>>> parameter. All the generated links within the application should
> >>>>> encode this parameter into the link (most likely in the query
> >>>>> string?). I could push the parameter into the session, but I want
> >>>>> the user to be able to bookmark the link and capture the parameter.
> >>>>>
> >>>>> For whatever reason it is not clear to me where this should be
> >>>>> hooked into the Tapestry framework...
> >
> >
> > Finally got back(!) to this particular problem, and after far too much
> > mucking around in the code, came up with an answer of sorts. What seems
> > to do the trick is to override the ILink implementations to change the
> > render used for links.
> >
> > For example the re-done PageLink class looks like:
> > --------------------------------------------------------------------
> > public abstract class PageLink extends AbstractLinkComponent {
> >
> > public ILink getLink(IRequestCycle cycle) {
> > String targetPage = getTargetPage();
> > INamespace namespace = getTargetNamespace();
> > String parameter = ((null == namespace) ? targetPage :
> > namespace.constructQualifiedName(targetPage));
> > IEngineService service =
> > cycle.getEngine().getService(Tapestry.PAGE_SERVICE);
> > ILink o = service.getLink(cycle,this,new String[] { parameter });
> > return o;
> > }
> > protected void finishLoad() {
> > setRenderer(DefaultLinkRenderer.SHARED_INSTANCE);
> > }
> > public abstract String getTargetPage();
> > public abstract INamespace getTargetNamespace();
> > }
> > --------------------------------------------------------------------
> >
> > Note the call to setRender() in finishLoad(), and that the class
> > DefaultLinkRenderer is in fact from an application (not from the
> > Tapestry library).
> >
> > The added parameter is built into the link by the DefaultLinkRenderer.
> > --------------------------------------------------------------------
> > public class DefaultLinkRenderer implements ILinkRenderer {
> >
> > // A shared instance used as a default for any link that doesn't
> > explicitly override.
> > public static final ILinkRenderer SHARED_INSTANCE = new
> > DefaultLinkRenderer();
> >
> > public void renderLink(IMarkupWriter writer, IRequestCycle cycle,
> > ILinkComponent linkComponent) {
> > if (null !=
> > cycle.getAttribute(Tapestry.LINK_COMPONENT_ATTRIBUTE_NAME)) {
> > throw new ApplicationRuntimeException(
> >
> > Tapestry.getMessage("AbstractLinkComponent.no-nesting"),
> > linkComponent,
> > null,
> > null
> > );
> > }
> >
> > cycle.setAttribute(Tapestry.LINK_COMPONENT_ATTRIBUTE_NAME,linkComponent);
> > if (linkComponent.isDisabled()) {
> > if (getHasBody()) {
> > linkComponent.renderBody(writer,cycle);
> > }
> > } else {
> > ILink l = linkComponent.getLink(cycle);
> > String url = l.getURL(linkComponent.getAnchor(),true);
> > String id = cycle.getRequestContext().getParameter("id");
> > url = url + "&id=" + id;
> > if (getHasBody()) {
> > writer.begin(getElement());
> > writer.attribute(getUrlAttribute(),url);
> > beforeBodyRender(writer,cycle,linkComponent);
> > IMarkupWriter wrappedWriter = writer.getNestedWriter();
> > linkComponent.renderBody(wrappedWriter,cycle);
> > afterBodyRender(writer,cycle,linkComponent);
> > linkComponent.renderAdditionalAttributes(writer,cycle);
> > wrappedWriter.close();
> > writer.end();
> > } else {
> > writer.beginEmpty(getElement());
> > writer.attribute(getUrlAttribute(),url);
> > beforeBodyRender(writer,cycle,linkComponent);
> > afterBodyRender(writer,cycle,linkComponent);
> > linkComponent.renderAdditionalAttributes(writer,cycle);
> > writer.closeTag();
> > }
> > }
> > cycle.removeAttribute(Tapestry.LINK_COMPONENT_ATTRIBUTE_NAME);
> > }
> >
> > protected String constructURL(ILink link, String anchor,
> > IRequestCycle cycle) {
> > return link.getURL(anchor,true);
> > }
> > protected void beforeBodyRender(IMarkupWriter writer, IRequestCycle
> > cycle, ILinkComponent link) {
> > // do nothing
> > }
> > protected void afterBodyRender(IMarkupWriter writer, IRequestCycle
> > cycle, ILinkComponent link) {
> > // do nothing
> > }
> > protected String getElement() {
> > return "a";
> > }
> > protected String getUrlAttribute() {
> > return "href";
> > }
> > protected boolean getHasBody() {
> > return true;
> > }
> > }
> > --------------------------------------------------------------------
> >
> > Doubtless the above is somewhat mangled by line wrap. This would better
> > be sent in HTML format, but though the rationale faded away long ago,
> > the ban remains.
> >
> > Whether the above solution is particularly elegant is an entirely
> > different question. It seems that link generation should be more a
> > top-level notion in the page generation model, perhaps.
> >
> >
> > ---------------------------------------------------------------------
> > 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]
>
>
--
Howard M. Lewis Ship
Independent J2EE / Open-Source Java Consultant
Creator, Jakarta Tapestry
Creator, Jakarta HiveMind
Professional Tapestry training, mentoring, support
and project work. http://howardlewisship.com
---------------------------------------------------------------------
To unsubscribe, e-mail: [EMAIL PROTECTED]
For additional commands, e-mail: [EMAIL PROTECTED]
