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Added by digi9ten, last edited by Don Brown on Jan 06, 2007 (view change)

## Description

A tag that creates a HTML <a href='' /> that when clicked calls a URL remote XMLHttpRequest call via the dojo framework.

THE FOLLOWING IS ONLY VALID WHEN AJAX IS CONFIGURED

- href
- errorText
- listenTopics
- notifyTopics
- executeScripts
- loadingText
- listenTopics
- handler
- formId
- formFilter
- targets
- showErrorTransportText
- targets
- indicator

'resultDivId' Deprecated. Use targets.

'targets' is a list of element ids whose content will be updated with the text returned from request.

'errorText' is the text that will be displayed when there is an error making the request.

'onLoadJS' Deprecated. Use 'notifyTopics'.

'preInvokeJS' Deprecated. Use 'notifyTopics'.

'executeScripts' if set to true will execute javascript sections in the returned text.

'loadingText' is the text that will be displayed on the 'targets' elements while making the request.

'handler' is the name of the function that will take care of making the AJAX request. Dojo's widget and dom node are passed as parameters).

'formId' is the id of the html form whose fields will be seralized and passed as parameters in the request.

'formFilter' is the name of a function which will be used to filter the fields that will be seralized. This function takes as a parameter the element and returns true if the element should be included.

'listenTopics' comma separated list of topics names, that will trigger a request 'indicator' element to be shown while the request executing 'showErrorTransportText': whether errors should be displayed (on 'targets')

'notifyTopics' comma separated list of topics names, that will be published. Three parameters are passed:

- data: html or json object when type='load' or type='error'
- type: 'before' before the request is made, 'load' when the request succeeds, or 'error' when it fails
- request: request javascript object, when type='load' or type='error'

| While this tag can be used with the simple theme, xhtml theme, and others, it is really designed to work best with the ajax theme. We recommend reading the ajax a template documentation for more details.

## Parameters

#### Name | #### Required | #### Default | #### Evaluated | #### Type | #### Description
--- | --- | --- | --- | --- | ---
accesskey | false |  | true | String | Set the html accesskey attribute on rendered html element
cssClass | false |  | true | String | The css class to use for element
cssStyle | false |  | true | String | The css style definitions for element ro use
disabled | false |  | true | String | Set the html disabled attribute on rendered html element
errorText | false |  | true | String | The text to display to the user if the is an error fetching the content
executeScripts | false | false | true | Boolean | Javascript code in the fetched content will be executed
formFilter | false |  | true | String | Function name used to filter the fields of the form.
formId | false |  | true | String | Form id whose fields will be serialized and passed as parameters
handler | false |  | true | String | Javascript function name that will make the request
href | false |  | true | String | The URL to call to obtain the content. Note: If used with ajax context, the value must be set as an url tag value.
id | false |  | true | String | id for referencing element. For UI and form tags it will be used as HTML id attribute
indicator | false |  | true | String | Id of element that will be shown while making request
key | false |  | true | String | Set the key (name, value, label) for this particular component
label | false |  | true | String | Label expression used for rendering a element specific label
labelposition | false |  | true | String | Define label position of form element (top/left)
listenTopics | false |  | true | String | Topic that will trigger the remote call
loadingText | false | Loading... | true | String | Text to be shown while content is being fetched
name | false |  | true | String | The name to set for element
notifyTopics | false |  | true | String | Topics that will published when the remote call completes
onLoadJS | false |  | true | String | Deprecated. Use 'notifyTopics'. Javascript code execute after reload
onblur | false |  | true | String | Set the html onblur attribute on rendered html element
onchange | false |  | true | String | Set the html onchange attribute on rendered html element
onclick | false |  | true | String | Set the html onclick attribute on rendered html element
ondblclick | false |  | true | String | Set the html ondblclick attribute on rendered html element
onfocus | false |  | true | String | Set the html onfocus attribute on rendered html element
onkeydown | false |  | true | String | Set the html onkeydown attribute on rendered html element
onkeypress | false |  | true | String | Set the html onkeypress attribute on rendered html element
onkeyup | false |  | true | String | Set the html onkeyup attribute on rendered html element
onmousedown | false |  | true | String | Set the html onmousedown attribute on rendered html element
onmousemove | false |  | true | String | Set the html onmousemove attribute on rendered html element
onmouseout | false |  | true | String | Set the html onmouseout attribute on rendered html element
onmouseover | false |  | true | String | Set the html onmouseover attribute on rendered html element
onmouseup | false |  | true | String | Set the html onmouseup attribute on rendered html element
onselect | false |  | true | String | Set the html onselect attribute on rendered html element
openTemplate | false |  | true | String | Set template to use for opening the rendered html.
preInvokeJS | false |  | true | String | Deprecated. Use 'notifyTopics'. Javascript code execute before reload
required | false | false | true | Boolean | If set to true, the rendered element will indicate that input is required
requiredposition | false |  | true | String | Define required position of required form element (left|right)
showErrorTransportText | false | true | true | Boolean | Set whether errors will be shown or not
tabindex | false |  | true | String | Set the html tabindex attribute on rendered html element
targets | false |  | true | String | Comma delimited list of ids of the elements whose content will be updated
template | false |  | true | String | The template (other than default) to use for rendering the element
templateDir | false |  | true | String | The template directory.
theme | false |  | true | String | The theme (other than default) to use for rendering the element
title | false |  | true | String | Set the html title attribute on rendered html element
tooltip | false |  | true | String | Set the tooltip of this particular component
tooltipConfig | false |  | true | String | Set the tooltip configuration
value | false |  | true | String | Preset the value of input element.

## Usage

To get started, use the head tag and the ajax theme. See ajax head template for more information. Then look at the usage details for the ajax a template.

If you want to use additional parameters in your s:a the best practice is to use a s:url to create your url and then leverage this url into your s:a tag. This is done by creating a s:url and specifying an id attribute.. like "testUrlId" in this example. Then in the s:a tag reference this id in the href attribute via " %{testUrlId}"

    <s:url id="testUrlId" namespace="/subscriber" action="customField" method="delete">
                      <s:param name="customFieldDefinition.id" value="${id}"/>
                  </s:url>
                 <s:a errorText="Sorry your request had an error." preInvokeJS="confirm('Are you sure you want to delete this item?')" href="%{testUrlId}">
                        <img src="<s:url value="/images/delete.gif"/>" border="none"/></s:a>

    <img xsrc="<s:url value="/images/delete.gif"/>" border="none"/></s:a><img xsrc="<s:url value="/images/delete.gif"/>" border="none"/></s:a>