Joomla! Documentation™

介紹

Form fields are fields in a HTML <form>. Joomla! 2.5 and newer supply the JForm class to conveniently and flexibly create forms with a many form fields. Each form field type is a subclass of JFormField.

In addition to being a flexible page creation tool, JFormFields are used by Joomla! to allow Administrators to configure Joomla! or its extensions without changing the underlying code. In Joomla! 1.5, this was handled by the now deprecated JParameter and JElement classes.

To define form fields in the configuration of an extension, you must include them in a named fieldset, such as <fieldset name="basic">, that is within the <fields name="params"> section of the <config> element in your XML manifest file.

== 表單驗證 ==

Joomla has client-side and server-side form validation capabilities.
Server side validation is essential since everything before that can be overridden on the user side by hackers. However client-side is the most user-friendly validation, so using both is considered best practice.

Client-side validation

.. is done via javascript while the user is filling in the form fields.
It uses the HTML classes required and validate-[xxx] (with [xxx] being a joomla or custom rule; e.g. validate-numeric)

More here: Client-side form validation

Server-side validation

.. is done after having submitted the form and will normally return to the form when not validated with some extra messages.
It uses the HTML attributes required ("true" or "required") and validate (with value being a joomla or custom rule; e.g. validate="email")

More here: Server-side form validation

== 標準表單欄位類型 ==

Numerous types of form field are built into Joomla!. The following table lists these standard types and their availability. Use the single-page reference if you want to print all existing form field documentation.

Please note that many of these fields are available as parameter types in Joomla! 1.5. For a list of parameter types, see J1.5:Standard parameter types. For a comparison between form field and parameter types, see Standard form field and parameter types.

Type	Description	Availability
accessiblemedia	provides modal access to the media manager for insertion of images with upload for users with appropriate permissions and a text field for adding a alternative text.	and newer
accesslevel	provides a drop down list of viewing access levels.	and newer
cachehandler	provides a list of available cache handling options.	and newer
calendar	provides a text box for entry of a date. An icon next to the text box provides a link to a pop-up calendar, which can also be used to enter the date value.	and newer
captcha	provides the use of a captcha plugin.	and newer
category	provides a drop down list of categories for an extension.	and newer
checkbox	provides a single checkbox to be checked or unchecked	and newer
checkboxes	provides unlimited checkboxes that can be used for multi-select.	and newer
Chrome Style	provides a list of template chrome style options grouped by template.	and newer
color	provides a color picker when clicking the input box.	and newer
Content Language	Provides a list of content languages.	and newer
Content Type	Provides a list of content types.	and newer
combo	provides a combo box field.	and newer
componentlayout	provides a grouped list of core and template alternative layouts for a component item.	and newer
contentlanguage	provides a list of installed content languages for use in conjunction with the language switcher plugin.	and newer
Database Connection	Provides a list of available database connections, optionally limiting to a given list.	and newer
editor	provides an editor area field.	and newer
editors	Provides a drop down list of the available WYSIWYG editors. Since use plugins form field instead.
email	provides an email field.	and newer
file	Provides an input field for files	and newer
filelist	provides a drop down list of files from a specified directory.	and newer
folderlist	provides a drop down list of folders from a specified directory.	and newer
groupedlist	provides a drop down list of items organized into groups.	and newer
header tag	provides a drop down list of the header tags (h1-h6).	and newer
helpsite	provides a drop down list of the help sites for your Joomla installation.	and newer
hidden	provides a hidden field for saving a form field whose value cannot be altered directly by a user in the Administrator (it can be altered in code or by editing the params.ini file).	and newer
imagelist	provides a drop down list of image files in a specified directory.	and newer
integer	provides a drop down list of integers between a minimum and maximum.	and newer
language	provides a drop down list of the installed languages for the Front-end or Back-end.	and newer
list	provides a drop down list of custom-defined entries.	and newer
media	provides modal access to the media manager for insertion of images with upload for users with appropriate permissions.	and newer
menu	provides a drop down list of the available menus from your Joomla site.	and newer
Menu Item	provides a drop down list of the available menu items from your Joomla site.	and newer
meter	Provides a meter to show value in a range.	and newer
Module Layout	provides a list of alternative layout for a module grouped by core and template.	and newer
Module Order	Provides a drop down to set the ordering of module in a given position	and newer
Module Position	provides a text input to set the position of a module.	and newer
Module Tag	provides a list of html5 elements (used to wrap a module in).	and newer
note	supports a one line text field.	and newer
number	Provides a one line text box with up-down handles to set a number in the field.	and newer
password	provides a text box for entry of a password. The password characters will be obscured as they are entered.	and newer
plugins	provides a list of plugins from a given folder.	and newer
predefinedlist	Form Field to load a list of predefined values.	and newer
radio	provides radio buttons to select different options.	and newer
range	Provides a horizontal scroll bar to specify a value in a range.	and newer
repeatable	Allows form fields which can have as many options as the user desires.	and newer
rules	provides a matrix of group by action options for managing access control. Display depends on context.	and newer
sessionhandler	provides a drop down list of session handler options.	and newer
spacer	provides a visual separator between form fields. It is purely a visual aid and no value is stored.	and newer
sql	provides a drop down list of entries obtained by running a query on the Joomla Database. The first results column returned by the query provides the values for the drop down box.	and newer
subform	provides a way to use XML forms inside each other or reuse your existing forms inside your current form.	and newer
tag	provides an entry point for tags (either AJAX or Nested).	and newer
tel	provides an input field for a telephone number.	and newer
templatestyle	provides a drop down list of template styles.	and newer
text	provides a text box for data entry.	and newer
textarea	provides a text area for entry of multi-line text.	and newer
timezone	provides a drop down list of time zones.	and newer
URL	provides a URL text input field.	and newer
user	Field to select a user from a modal list. Displays User Name and stores User ID	and newer
useractive	Field to show a list of available user active statuses.	and newer
usergroup	provides a drop down list of user groups. Since use usergrouplist instead.	and newer
usergrouplist	Field to load a drop down list of available user groups. Replaces usergroup form field type.	and newer
userstate	Field to load a list of available users statuses.	and newer

== 客製化表單欄位類型 == An extension can define its own form field types that can then be used in its own forms or forms created by another extension. See Creating a custom form field type for instructions.

Modal Form Field Types

If you have a field with many values that don't fit a selection box, you can always make a modal form field that will allow the user to pick an item from a modal page with a table, filtering options, etc. (Just like any administrator table, e.g. "Articles".) See Creating a modal form field

== 通用屬性 == === Labelclass ===

使用labelclass 屬性來為欄位標籤新增 CSS clasl. Source:

http://joomlacode.org/gf/project/joomla/tracker/?action=TrackerItemEdit&tracker_item_id=28450

=== Showon === Adding the attribute showon allows you to hide the field based on the value(s) of another field.

The syntax to show the field bar only when foo is set to "1" and baz is set to "1":

<field
    name="foo"
    type="list"
    >
    <option value="1">JYES</option>
    <option value="0">JNO</option>
</field>
<field
    name="bar"
    type="text"
    showon="foo:1"
/>

To match multiple values one can provide a comma-separated list of values such as showon="foo:1,2"

To combine multiple fields, use [AND] as in showon="foo:1[AND]bar:1"

The syntax to show the field bar only when "foo" is set to "1" and baz is set to "1":

<field
    name="foo"
    type="list"
    >
    <option value="1">JYES</option>
    <option value="0">JNO</option>
</field>
<field
    name="baz"
    type="list"
    >
    <option value="1">JYES</option>
    <option value="0">JNO</option>
</field>
<field
    name="bar"
    type="text"
    showon="foo:1[AND]baz:1"
/>

To create a choice among multiple fields, use [OR] as in showon="foo:1[OR]bar:1".

The syntax to show the field bar only when foo is set to "1" or baz is set to "1":

<field
    name="foo"
    type="list"
    >
    <option value="1">JYES</option>
    <option value="0">JNO</option>
</field>
<field
    name="baz"
    type="list"
    >
    <option value="1">JYES</option>
    <option value="0">JNO</option>
</field>
<field
    name="bar"
    type="text"
    showon="foo:1[OR]baz:1"
/>

You can also use value 'does not equal' as in showon="field1!:1".

The syntax to show the field "bar" only when "foo" is not equal to "1":

<field
    name="foo"
    type="list"
    >
    <option value="1">JYES</option>
    <option value="0">JNO</option>
</field>
<field
    name="baz"
    type="list"
    showon="foo!:1"
    >
    <option value="1">JYES</option>
    <option value="0">JNO</option>
</field>

To show a field when another field (e.g. foo) has been selected (when that other field is not empty), use showon="foo!:" (without a value specified).

This was introduced with a pull request, available starting with Joomla 3.2.4.

Troubleshooting: Attributes Not Working

If you have read an older version of our developer documentation, or took your form display code from an existing extension, you may be experiencing issues with attributes like showon not working at all. In order for some special attributes to function, your fields must be rendered using their renderField() method. For example:

<div class="row-fluid">
    <div class="span6">
        <?php
            foreach($this->form->getFieldset() as $field) {
                echo $field->renderField();
            }
        ?>
    </div>
</div>