Actually, I mean this link: http://wiki.java.net/bin/view/Projects/FaceletsTaglibFiles
There is java code embedded in the examples for tags that cannot be handled entirely in taglib.xml files. It'd probably be nice if someone created an index into that page's java code examples and added them to the other example page too. For a well-written component (one that doesn't put component logic into the jsp tag handler), the only time you'd need a component tag handler is to specify MethodRules. In all the other cases, you'd be better off fixing the component itself provided you had the soruce code. On 12/12/06, Martin Grotzke <[EMAIL PROTECTED]> wrote:
On Tue, 2006-12-12 at 10:54 -0500, Mike Kienenberger wrote: > Another resource to consider when writing facelets componenthandlers > and taghandlers is the facelets wiki. There's a few examples > available there. Do you mean http://wiki.java.net/bin/view/Projects/FaceletsExamples? These are examples that show what can be done, but now how... > 90% of the time, it's simply a matter of applying a > MethodRule since method signatures are the one thing that facelets > cannot autodetect :-) This is good to know, and then it's even better to have the MethodRule ;-) Cheers, Martin > > > On 12/12/06, Martin Grotzke <[EMAIL PROTECTED]> wrote: > > Hello Mike, > > > > On Mon, 2006-12-11 at 15:37 -0500, Mike Kienenberger wrote: > > > I think you made the facelets tag handler harder that necessary. Not > > > sure about the "void.class" syntax below, but you can probably figure > > > out the correct syntax. > > Thanx a lot, this is a great simplification! (and the void.class is > > correct :)) > > I wrote the tag handler according to what I've seen in the facelets > > sources, knew (read) nothing about MethodRule :) > > > > Thanx again, > > cheers, > > Martin > > > > > > > > > > > > > private static final String ACTION_LISTENER_ATT_NAME = > > > "toggleDetailActionListener"; > > > > > > public final static Class[] ACTION_LISTENER_SIG = new Class[] { > > > ActionEvent.class }; > > > protected final static MethodRule actionListenerTagRule > > > = new MethodRule(ACTION_LISTENER_ATT_NAME, void.class, > > > ACTION_LISTENER_SIG); > > > > > > public CustomHtmlDataTableHandler(ComponentConfig config) { > > > super( config ); > > > } > > > > > > protected MetaRuleset createMetaRuleset(Class type) > > > { > > > MetaRuleset m = super.createMetaRuleset(type); > > > > > > m.addRule(actionListenerTagRule); > > > > > > return m; > > > } > > > > > > On 12/11/06, Martin Grotzke <[EMAIL PROTECTED]> wrote: > > > > On Mon, 2006-12-11 at 20:37 +0100, Martin Grotzke wrote: > > > > > On Mon, 2006-12-11 at 09:44 -0700, Andrew Robinson wrote: > > > > > > "When myBean.myModel.myOptions is invoked the first time, I do some > > > > > > lazy > > > > > > initialization, this might cause errors..." > > > > > > > > > > > > I would recommend that you load this data in the on load method of > > > > > > your page. This way, if it fails, you can handle the error in any way > > > > > > you want, including redirecting to an error page. > > > > > I cannot do this, because I have to initialize the detailStamps of > > > > > all rows separately: the details of one item cause several backend > > > > > requests that might cost money, and they definitively need time > > > > > to return (several seconds per request). > > > > > > > > > > Now I wrote a CustomHtmlDataTable (extending HtmlDataTable) that > > > > > provides an additional MethodBinding "toggleDetailActionListener". > > > > > > > > Btw, I just posted the complete example here: > > > > http://www.javakaffee.de/blog/2006/12/11/how-to-add-a-new-attribute-to-an-existing-jsf-component-using-facelets/ > > > > > > > > Perhaps it's useful for someone... > > > > > > > > Cheers, > > > > Martin > > > > > > > > > > > > > > > > > > > > > > > The toggleDetail method is extended so that it invokes also the method > > > > > binding if it's provided. > > > > > > > > > > The hardest thing was to write the facelets MetaTagHandler that sets > > > > > the attribute on the CustomHtmlDataTable: > > > > > > > > > > public final class CustomHtmlDataTableHandler extends ComponentHandler { > > > > > > > > > > public CustomHtmlDataTableHandler(ComponentConfig config) { > > > > > super( config ); > > > > > } > > > > > > > > > > protected MetaRuleset createMetaRuleset(Class type) { > > > > > return super.createMetaRuleset(type).addRule( ActionSourceRule.Instance ); > > > > > } > > > > > > > > > > static final class ActionSourceRule extends MetaRule { > > > > > > > > > > private static final String ACTION_LISTENER_ATT_NAME = "toggleDetailActionListener"; > > > > > > > > > > public final static Class[] ACTION_LISTENER_SIG = new Class[] { ActionEvent.class }; > > > > > > > > > > final static class ActionListenerMapper extends Metadata { > > > > > > > > > > private final TagAttribute attr; > > > > > > > > > > public ActionListenerMapper(TagAttribute attr) { > > > > > this.attr = attr; > > > > > } > > > > > > > > > > public void applyMetadata(FaceletContext ctx, Object instance) { > > > > > ((CustomHtmlDataTable) instance) > > > > > .setToggleDetailActionListener( new LegacyMethodBinding(this.attr > > > > > .getMethodExpression(ctx, null, > > > > > ActionSourceRule.ACTION_LISTENER_SIG))); > > > > > } > > > > > > > > > > } > > > > > > > > > > public final static ActionSourceRule Instance = new ActionSourceRule(); > > > > > > > > > > public ActionSourceRule() { > > > > > super(); > > > > > } > > > > > > > > > > public Metadata applyRule(String name, TagAttribute attribute, > > > > > MetadataTarget meta) { > > > > > if (meta.isTargetInstanceOf(CustomHtmlDataTable.class)) { > > > > > > > > > > if (ACTION_LISTENER_ATT_NAME.equals(name)) { > > > > > return new ActionListenerMapper(attribute); > > > > > } > > > > > } > > > > > return null; > > > > > } > > > > > } > > > > > > > > > > } > > > > > > > > > > > > > > > I hope this is basically the correct approach... > > > > > > > > > > Cheers, > > > > > Martin > > > > > > > > > > > > > > > > > > > > > Use one of these technologies: > > > > > > > > > > > > 1) JBoss-Seam. Set the action to run in the pages.xml file. Example: > > > > > > > > > > > > <page view-id="/index.xhtml" > > > > > > action="#{welcomeBean.onLoad}" /> > > > > > > > > > > > > 2) On-load from jsf-comp: > > > > > > http://jsf-comp.sourceforge.net/components/onload/index.html > > > > > > > > > > > > 3) or use Shale (I have no experience with this one): > > > > > > http://shale.apache.org/shale-view/index.html > > > > > > > > > > > > -Andrew > > > > > > > > > > > > On 12/11/06, Martin Grotzke <[EMAIL PROTECTED]> wrote: > > > > > > On Mon, 2006-12-11 at 10:29 -0500, Simon Lessard wrote: > > > > > > > Hello Martin, > > > > > > > > > > > > > > Can you provide a mopre explicit example of the use case > > > > > > please? > > > > > > Sorry for the few words, if you think about a problem for > > > > > > several days > > > > > > to you it seems just too clear ;) > > > > > > > > > > > > What I have is a datatable in a template with the detailStamp > > > > > > facet: > > > > > > > > > > > > <table jsfc="t:dataTable" > > > > > > ... > > > > > > value="#{myBean.myModel}" > > > > > > var="myItem" > > > > > > varDetailToggler="detailToggler"> > > > > > > > > > > > > ... some columns ... > > > > > > > > > > > > <span jsfc="f:facet" name="detailStamp"> > > > > > > <ui:include src=" itemdetails.xhtml"> > > > > > > <ui:param name="item" > > > > > > value="#{myItem}"/> > > > > > > </ui:include> > > > > > > </span> > > > > > > </table> > > > > > > > > > > > > The itemdetails.xhtml displays details to the item, e.g. it > > > > > > iterates > > > > > > over some detail options like the following: > > > > > > > > > > > > <ui:repeat var="option" value="#{item.myOptions}"> > > > > > > #{option.description} > > > > > > </ui:repeat> > > > > > > > > > > > > So the the myBean.myModel.myOptions method is requested when > > > > > > the detailStamp > > > > > > is displayed for one item, this method is invoked when > > > > > > rendering happens. > > > > > > > > > > > > When myBean.myModel.myOptions is invoked the first time, I do > > > > > > some lazy > > > > > > initialization, this might cause errors... > > > > > > > > > > > > I do not see how I could do the processing in the invoke > > > > > > application, because > > > > > > the detailStamp is shown via HtmlDataTable.toggleDetail, which > > > > > > is invoked > > > > > > during invoke-application, but there's no possibility of > > > > > > specifying a listener > > > > > > that is invoked when toggleDetail is invoked... > > > > > > > > > > > > I hope this clarifies the problem a little bit, if s.th. is > > > > > > missing please > > > > > > let me know! > > > > > > > > > > > > Thanx a lot, > > > > > > cheers, > > > > > > Martin > > > > > > > > > > > > > > > > > > > > > > > > > Why can't you do the processing in the invoke application > > > > > > phase? > > > > > > > Without more details, all I could suggest is to use a render > > > > > > response > > > > > > > phase listener and add your logic in the beforePhase > > > > > > method. > > > > > > > > > > > > > > > > > > > > > Regards, > > > > > > > > > > > > > > ~ Simon > > > > > > > > > > > > > > On 12/11/06, Martin Grotzke <[EMAIL PROTECTED]> > > > > > > wrote: > > > > > > > Hi all, > > > > > > > > > > > > > > I have a case where I perform some logic during the > > > > > > > RENDER_RESPONSE > > > > > > > phase where an error might occurs and I want to > > > > > > display some > > > > > > > error > > > > > > > message - which is unfortunately not displayed > > > > > > directly. But > > > > > > > with the > > > > > > > next request/response the error message is > > > > > > displayed. I asume > > > > > > > that this > > > > > > > is the case because the h:messages component is > > > > > > already > > > > > > > rendered - so > > > > > > > the behavior should basically be correct. > > > > > > > > > > > > > > Do you have any suggestions how to handle this? > > > > > > > > > > > > > > The concrete case is when the details of a dataTable > > > > > > (facet > > > > > > > detailStamp) > > > > > > > are displayed - just comes into my mind to use a > > > > > > > CustomHtmlDataTable > > > > > > > component that overrides the toggleDetail method... > > > > > > What do > > > > > > > you think? > > > > > > > > > > > > > > Thanx in advance, > > > > > > > cheers, > > > > > > > Martin > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > -- > > > > > > Martin Grotzke > > > > > > http://www.javakaffee.de/blog/ > > > > > > > > > > > > > > > > > > > > > > -- > > > > Martin Grotzke > > > > http://www.javakaffee.de/blog/ > > > > > > > > > > > > > > > > > -- > > Martin Grotzke > > http://www.javakaffee.de/blog/ > > > > > > > -- Martin Grotzke http://www.javakaffee.de/blog/
