XForms/Input Field Width

Motivation

Sometimes you want to be able to control the field width, even though the default input text scrolls. This can be done for the entire form or for on a field-by-field basis for all input fields within a form. For example if you have three places that a person's last name occurs they can all be controlled by changing a single CSS file that is imported into the form. This CSS file can also be generated directly from an XML Schema or metadata registry using XML transforms.

Screen Image

Screen Image of CSS controled field widths using the FireFox XForms extension and the .xf-value selector

    <fieldset name="image_info" legend="Image Information">
<field name="subjectWeight"        type="text"         label="Subject Weight:"                   maxlength="10"   size="15" /><label="Kg">
</filedset>

Discussion

There are many tradeoffs as to where to put form width information. Ideally it would be generated by a script from a metadata registry. One of the questions concerns if a data element length should only have a default recommended value in a semantic registry and the actual constraints be stored in a constraint schema. We all know that zip codes should be 5 or 9 digits and that a 12 digit zip code may only have meaning in a specific context.

This example has been tested using the FireFox browser. The use of the .xf-value class selector may not work on other systems.