ZK Component Reference/XHTML Components

All XHTML components are derived from AbstractTag.

An XHTML component is a thin wrapper that encapsulates a native HTML tag. It is different to a XUL component or other none-native component in several ways.

• By implementing the RawId interface, the universal identifier, getUuid, is the same as the identifier getId.
• By implementing the DynamicAttributes interface, all XHTML components support arbitrary attributes. In other words, any attribute name is legal (as long as the targeted browser supports).

Encoding URLs

A XHTML component generates attributes directly to native HTML tags. It means, unlike XUL, it doesn't prefix the servlet context path to attributes for specifying URL. For example, the following codes don't work (unless the servlet context is "").

 <img href="/my/good.png"/>

Instead, you should use the encodeURL function in EL expressions as follows.

 <?taglib uri="http://www.zkoss.org/dsp/web/core.dsp.tld" prefix="p"?>
 ...
 <img href="${p:encodeURL('/my/good.png')}"/>

In Java, you should use the method, Execution.encodeURL(String).

 <img id="another"/>
 <zscript>
   another.setDynamicAttribute("href",
     Executions.getCurrent().encodeURL("/my/good.png"));
 </zscript>

Notice that XUL components and all ZK features that accept a URL will invoke the encodeURL method automatically. The reason why we do not handle XHTML components is that we do not know which attribute requires a URL.

Raw

A special component, Raw is used to represent any component that is not declared in the following section (i.e., not in lang.xml). In other words, if any unrecognized component name is found, an instance of Raw is created and a proper HTML tag will be generated accordingly. In other words, any component name is legal as long as the targeted browser supports.

<marquee align="top">...</marquee>

is equivalent to

new Raw().setDynamicAttribute("align", "top");