Re: [jsr-314-open] Ajax rendering of components among compositions?

Gang - There is one obviously critical piece of information missing here that clearly needs to be described more explicitly within the spec/pdldocs. The format for the execute/render ids in the f:ajax tag matches the format for ids that are passed to findComponent(). That is... ids that do not start with the naming container separator character are treated as relative to the current naming container. Ids that do start with the separator character are treated as absolute ids - ie. are resolved relative to the UIViewRoot. So, for example, let's say we have the following component tree where we use f:subview to introduce a naming contianer <f:view> <f:subview id="namingContainer"> <h:commandButton id="insideButton"/> <h:graphicImage id="insideImage"/> </f:subview> <h:graphicImage id="outsideImage"/> </f:view> If we want to Ajax-enable the "insideButton" to target the "insideImage, we would use the following f:ajax tag: <f:ajax render="insideImage"/> If, on the other hand, we want to target the "outerImage", which is outside of the naming container, then we must use an "absolute id", eg: <f:ajax render=":outsideImage"/> (Note the leading ":" character.) This is similar to calling insideButtonComponent.findComponent(":outsideImage") - ie. this will start the search for the "outsideImage" id up at the root naming container. The fact that the pdldocs do not describe the format for execute/render ids is clearly a spec bug that needs to be addressed. I will open a bug to track this in a moment. This behavior is defined in the actual spec document itself in section 10.4.1.1 under the title 'Specifying “execute”/”render” Identifiers'. But even that section could use some clarification (eg. could use an example like the one above to illustrate the behavior). David Geary wrote On 5/24/2009 11:39 PM ET: > Notice the <f:ajax> tag. I think I'm accessing the image from the > parent component (map.xhtml) correctly. However, when I load the page > I get this: > > <f:ajax> contains an unknown id > 'form:j_id1186681689_16ef8569:0:j_id1186681689_16ef8513:j_id-1105909415_41ead6fe:image' > If I had to guess (haven't looked at the implementation yet), the issue is that we are searching for this id relative to the composite component's naming container. Since this particular id is not present under the composite component, we do not find the target component. We should make this error message more explicit - ie. we should include the id of the naming container within which we searched for the id. > > If I remove the f:ajax tag, load the page, and check the source, I > see an <img> tag: > > <img > id="form:j_id1186681689_16ef8569:0:j_id1186681689_16ef8513:j_id-1105909415_41ead6fe:image" > src="..."/> > > And that id is *exactly* what <f:ajax> says it cannot find. It's in > the page, but <f:ajax> cannot find it?!? > > My guess is that <f:ajax> is evaluating the id before the page is > completely constructed, and therefore, it doesn't find it, but that's > just a WAG on my part. You'll need to use the ":" prefix within your render id to indicate that you are specifying an absolute id. If that does not work, then my guess is that there is an implementation bug here. Andy