Extra attributes from Spring <form:form>

For jQuery Mobile I need markup like:

<form action="..." method="get" data-ajax="false">
    <!-- Fields -->
</form>
开发者_运维技巧

Since I work with Spring, I really like what <form:form> is doing for me, with all the convenient bindings, generating fields etc.

How can I make <form:form> print the extra attribute?

---

The <form:form> tag will allow arbitrary attributes.

<form:form commandName="blah" data-ajax="false">

Will work just fine.

---

You could create a custom JSP tag that extends the standard Spring tag. By overriding the writeOptionalAttributes method, you can add the additional attributes you require. For example

public class FormTag
    extends org.springframework.web.servlet.tags.form.FormTag {

    private String dataAjax;

    /* (non-Javadoc)
     * @see org.springframework.web.servlet.tags.form.AbstractHtmlElementTag#writeOptionalAttributes(org.springframework.web.servlet.tags.form.TagWriter)
     */
    @Override
    protected void writeOptionalAttributes(final TagWriter tagWriter) throws JspException {
        super.writeOptionalAttributes(tagWriter);

        writeOptionalAttribute(tagWriter, "data-ajax", getDataAjax());
    }


    /**
     * Returns the value of dataAjax
     */
    public String getDataAjax() {
        return dataAjax;
    }


    /**
     * Sets the value of dataAjax
     */
    public void setDataAjax(String dataAjax) {
        this.dataAjax = dataAjax;
    }

}

You then need to use a custom TLD that makes the new attribute(s) available to the JSP engine. I've only shown a snippet of it here, as its a copy & paste from the Spring original, with just your additional attribute added.

<?xml version="1.0" encoding="ISO-8859-1"?>
<!DOCTYPE taglib PUBLIC "-//Sun Microsystems, Inc.//DTD JSP Tag Library 1.2//EN"
                        "http://java.sun.com/dtd/web-jsptaglibrary_1_2.dtd">
<taglib>
    <tlib-version>1.0</tlib-version>
    <jsp-version>1.2</jsp-version>
    <short-name>custom-form</short-name>
    <uri>http://www.your.domain.com/tags/form</uri>
    <description>Custom Form Tag Library</description>
    <!-- <form:form/> tag -->
    <tag>
        <name>form</name>
        <tag-class>com.your.package.tag.spring.form.FormTag</tag-class>
        <body-content>JSP</body-content>
        <description>Renders an HTML 'form' tag and exposes a
            binding path to inner tags for binding.</description>
        <attribute>
            <name>id</name>
            <rtexprvalue>true</rtexprvalue>
            <description>HTML Standard Attribute</description>
        </attribute>
....
        <attribute>
            <name>dataAjax</name>
            <rtexprvalue>true</rtexprvalue>
            <description>jQuery data ajax attribute</description>
        </attribute>

put the new TLD file into the META-INF directory of your web app, then include it in your JSP as normal

<%@ taglib prefix="custom-form" uri="http://www.your.domain.com/tags/form" %>

And instead of using

<form:form> 

use

<custom-form:form dataAjax="false">