“ ui：fragment”中的“ rendered”属性

Question

I want to use the rendered attribute in a ui:fragment to conditionally render a span element in my JSF 2.2 facelet. The JSF 2.2 documentation of ui:fragment lists rendered as an allowed attribute. I am using MyFaces 2.2.12 as JSF implementation, however, and the MyFaces 2.2 documentation of ui:fragment does not list rendered as a valid attribute.

I tried using rendered anyway, and it worked. However, my IDE - IntelliJ - rightly highlights the rendered attribute as an error and tells me it is not allowed in the ui:fragment element.

I saw a response in ui:fragment rendered attribute not working after upgrading Facelets to JSF 2 that there was a documentation bug where rendered falsly wasn't listed in the JSF 2.0 documentation, but the response says nothing about JSF 2.2 or MyFaces 2.2 (presumably because it dates before the release of JSF 2.2).

Is the missing rendered attribute in the MyFaces documentation also just a bug?

With multiple such occurances of the ui:fragment element in a single Facelets file, these "false" errors make finding real errors quite cumbersome. What is the recommended solution for this problem, if it really is just a bug in the documentation?

Answer 1

rendered is valid attribute in ui:fragment and ui:component in JSF 2.0, 2.1, 2.2. See JSF 2.2 View Declaration Language .

Some IDEs do not propose this attribute in autocomplete (content assistant) mode and validate it as "Unknown attribute". This happens because the rendered attribute was missing in the tag file declaration in JSF 2.0 (even if attribute was presented in the UIComponent) and the IDE validation is based on the tag file declarations. Issue was fixed in JSF 2.1: the missing attribute was added into the tag file declaration. Validation in IDE not always reflect to this change.