radio

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An element that can be turned on and off. Radio buttons are almost always listed together in groups. Only one radio button within the same radiogroup may be selected at a time. The user can switch which radio button is turned on by selecting it with the mouse or keyboard. Other radio buttons in the same group are turned off. A label, specified with the label attribute may be added beside the radio button.

More information is available in the XUL tutorial.

Attributes: accesskey, command, crop, disabled, focused, group, image, label, selected, tabindex, value

Properties: accessKey, accessibleType, control, crop, disabled, image, label, radioGroup, selected, tabIndex, value

Examples

<radiogroup>
  <radio id="orange" label="Red" accesskey="R"/>
  <radio id="violet" label="Green"  accesskey="G" selected="true"/>
  <radio id="yellow" label="Blue"  accesskey="B" disabled="true"/>
</radiogroup>

Attributes

accesskey: Type: character; This should be set to a character that is used as a shortcut key. This should be one of the characters that appears in the label attribute for the element.

command: Type: id; Set to the id of a command element that is being observed by the element.

crop

Type: one of the values below

If the label of the element is too big to fit in its given space, the text will be cropped on the side specified by the crop attribute. An ellipsis will be used in place of the cropped text. If the box direction is reversed, the cropping is reversed.

start: The text will be cropped on its left side in left-to-right text locales, and the right side in right-to-left locales.
end: The text will be cropped on its right side in left-to-right text locales, and the right side in right-to-left locales.
left: The text will be cropped on its left side.
right: The text will be cropped on its right side.
center: The text will be cropped in the middle, showing both the start and end of the text normally.
none: The text will be not be cropped using an ellipsis. However, the text will simply be cut off if it is too large. The side depends on the CSS text alignment.

Depending on the platform and theme being used, some elements will have set a maximum width so they will always appear cropped. If you wish to use the value none and the displayed text is larger than this maximum width, you may be able to use the max-width CSS property (or the maxwidth attribute) to override this size. For example, for a menuitem in a menu you can add the following CSS rule when you want to use the value none:

menupopup > menuitem, menupopup > menu { max-width: none; }

disabled: Type: boolean; Indicates whether the element is disabled or not. If this attribute is set, the element is disabled. Disabled elements are usually drawn with grayed-out text. If the element is disabled, it does not respond to user actions, it cannot be focused, and the command event will not fire. In the case of form elements, it will not be submitted. Do not set the attribute to true, as this will suggest you can set it to false to enable the element again, which is not the case.
The disabled attribute is allowed only for form controls. Using it with an anchor tag (an <a> link) will have no effect.

The element will, however, still respond to mouse events. To enable the element, leave this attribute out entirely.; Visible controls have a disabled property which, except for menus and menuitems, is normally preferred to use of the attribute, as it may need to update additional state.

focused: Type: boolean; This attribute is true if the element is focused.

group: Type: string group name; Buttons with type="radio" and the same value for their group attribute are put into the same group. Only one button from each group can be checked at a time. If the user selects one the buttons, the others in the group are unchecked.

image: Type: URI; The URI of the image to appear on the element. If this attribute is empty or left out, no image appears. The position of the image is determined by the dir and orient attributes.

label: Type: string; The label that will appear on the element. If this is left out, no text appears. For an editable menuitem element the value of this attribute is copied to the menulist.value property upon user selection of the menuitem.

selected: Type: boolean; Indicates whether the element is selected or not. This value is read-only. To change the selection, set either the selectedIndex or selectedItem property of the containing element.
In Thunderbird (Sept. 2020), value is used.; Note that in multiprocess Firefox, this attribute means only that the user (or code) has initiated tab selection, not that the browser has actually switched to the tab. If your code needs to apply some styling to the currently selected tab, you should use the visuallyselected attribute, which is available from Firefox 40 onwards. See tab selection in multiprocess Firefox for more details.

tabindex: Type: integer; The tab order of the element. The tab order is the order in which the focus is moved when the user presses the "tab" key. Elements with a higher tabindex are later in the tab sequence.

value: Type: string; The string attribute allows you to associate a data value with an element. It is not used for any specific purpose, but you can access it with a script for your own use. Be aware, however, that some elements, such as textbox will display the value visually, so in order to merely associate data with an element, you could 1) Use another attribute like "value2" or "data-myAtt" (as in the HTML5 draft), as XUL does not require validation (less future-proof); 2) Use setAttributeNS() to put custom attributes in a non-XUL namespace (serializable and future-proof); 3) Use setUserData() (future-proof and clean, but not easily serializable). For user editable menulist elements, the contents, as visible to the user, are read and set using the Menulist.value syntax. For those elements, setAttribute("value", myValue) and getAttribute("value") do not access or affect the contents displayed to the user.

In Thunderbird (Sept. 2020), value is used to preset the radio from the radiogroup.

Properties

accessKey: Type: character; Gets and sets the value of the accesskey attribute.

accessibleType: Type: integer; A value indicating the type of accessibility object for the element.

control: Type: radiogroup element; Returns the enclosing radiogroup that the radio element is contained within, which may or may not be its direct parent.

crop: Type: string; Gets and sets the value of the crop attribute.

disabled: Type: boolean; Gets and sets the value of the disabled attribute.

image: Type: image URL; Gets and sets the value of the image attribute.

label: Type: string; Gets and sets the value of the label attribute.

radioGroup: Type: radiogroup element; Equivalent to the control property.

selected: Type: boolean; This property's value is true if this element is selected, or false if it is not. This property is read only. This property is available for menuitem and menuseparator elements in Firefox 3.

tabIndex: Type: integer; Gets and sets the value of the tabindex attribute.

value: Type: string; Gets and sets the value of the value attribute. For textbox and user editable menulist elements, the contents, as visible to the user, are read and set using the Textbox.value and Menulist.value syntax.

Methods

Inherited Methods
addEventListener(), appendChild(), blur, click, cloneNode(), compareDocumentPosition, dispatchEvent(), doCommand, focus, getAttribute(), getAttributeNode(), getAttributeNodeNS(), getAttributeNS(), getBoundingClientRect(), getClientRects(), getElementsByAttribute, getElementsByAttributeNS, getElementsByClassName(), getElementsByTagName(), getElementsByTagNameNS(), getFeature, getUserData, hasAttribute(), hasAttributeNS(), hasAttributes(), hasChildNodes(), insertBefore(), isDefaultNamespace(), isEqualNode, isSameNode, isSupported(), lookupNamespaceURI, lookupPrefix, normalize(), querySelector(), querySelectorAll(), removeAttribute(), removeAttributeNode(), removeAttributeNS(), removeChild(), removeEventListener(), replaceChild(), setAttribute(), setAttributeNode(), setAttributeNodeNS(), setAttributeNS(), setUserData

Elements: radiogroup, checkbox

Interfaces: nsIAccessibleProvider, nsIDOMXULSelectControlItemElement, nsIDOMXULLabeledControlElement