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

| Please make sure you have read the Tag Syntax document and understand how tag attribute syntax works.

## Description

The combo box is basically an HTML INPUT of type text and HTML SELECT grouped together to give you a combo box functionality. You can place text in the INPUT control by using the SELECT control or type it in directly in the text field.

In this example, the SELECT will be populated from id=year attribute. Counter is itself an Iterator. It will span from first to last. The population is done via javascript, and requires that this tag be surrounded by a <form>.

Note that unlike the <s:select/> tag, there is no ability to define the individual <option> tags' id attribute or content separately. Each of these is simply populated from the toString() method of the list item. Presumably this is because the select box isn't intended to actually submit useful data, but to assist the user in filling out the text field.

## 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
emptyOption | false |  | true | String | Decide if an empty option is to be inserted. Default false.
headerKey | false |  | true | String | Set the header key for the header option.
headerValue | false |  | true | String | Set the header value for the header option.
id | false |  | true | String | id for referencing element. For UI and form tags it will be used as HTML id attribute
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)
list | true |  | true | String | Iteratable source to populate from. If this is missing, the select widget is simply not displayed.
listKey | false |  | true | String | Set the key used to retrive the option key.
listValue | false |  | true | String | Set the value used to retrive the option value.
maxLength | false |  | true | Integer | Deprecated. Use maxlength instead.
maxlength | false |  | true | Integer | HTML maxlength attribute
name | false |  | true | String | The name to set for element
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
readonly | false | false | true | Boolean | Whether the input is readonly
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)
size | false |  | true | Integer | HTML size attribute
tabindex | false |  | true | String | Set the html tabindex attribute on rendered html element
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.

## Examples

    JSP:
    <-- Example One -->
    <s:bean name="struts.util.Counter" id="year">
      <s:param name="first" value="text('firstBirthYear')"/>
      <s:param name="last" value="2000"/>

      <s:combobox label="Birth year" size="6" maxlength="4" name="birthYear" list="#year"/>
    </s:bean>

    <-- Example Two -->
    <s:combobox
        label="My Favourite Fruit"
        name="myFavouriteFruit"
        list="{'apple','banana','grape','pear'}"
        headerKey="-1"
        headerValue="--- Please Select ---"
        emptyOption="true"
        value="banana" />

    <-- Example Two -->
    <s:combobox
       label="My Favourite Color"
       name="myFavouriteColor"
       list="#{'red':'red','green':'green','blue':'blue'}"
       headerKey="-1"
       headerValue="--- Please Select ---"
       emptyOption="true"
       value="green" />

    Velocity:
    #tag( ComboBox "label=Birth year" "size=6" "maxlength=4" "name=birthYear" "list=#year" )