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A single tab which should be placed inside a tabs
element. The user may click a tab to bring the associated page of the tabbox
to the front.
More information is available in the XUL tutorial.
- Attributes
- accesskey, afterselected, beforeselected, command, crop, disabled, first-tab, image, label, last-tab, linkedpanel, oncommand, pending, pinned, selected, tabindex, unread, validate, value
- Properties
- accessKey, accessibleType, command, control, crop, disabled, image, label, linkedPanel, selected, tabIndex, value
Examples
(example needed)
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
label for the element.
-
afterselected
- Type: boolean
- This is set to
true
if the tab is immediately after the currently selected tab. This is automatically set when needed and you shouldn't adjust it manually. This is primarily useful for themes so that they can adjust the appearance of the area around the selected tab.
-
beforeselected
- Type: boolean
- This is set to
true
if the tab is immediately before the currently selected tab. This is set automatically set when needed and you shouldn't adjust it manually. This is primarily useful for themes so that they can adjust the appearance of the area around the selected tab.
-
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 valuenone
: -
menupopup > menuitem, menupopup > menu { max-width: none; }
-
disabled
- Type: boolean
-
Indicates whether the element is disabled or not. If this element is set to
true
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 thecommand
event will not fire. -
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.
fadein
- Type: boolean
- This attribute is set to
true
if the tab is fading in or out. This typically means that the tab is in the process of appearing or disappearing.
-
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 themenulist
.value property upon user selection of themenuitem
.
linkedpanel
- Type: id
- The
id
of the linkedtabpanel
element that will be displayed when the tab is selected. If this attribute is not used, the tab will be connected to the panel at the corresponding index in thetabpanels
element that thetab
is in itstabs
container. However, if this attribute is used, this behavior is overridden, and the tab will always be linked to a specific panel. This might be used to avoid duplication by linking several tabs to one panel with slight differences to the content adjusted in the select event.
oncommand
- Type: script code
- This event handler is called when the command is activated. This occurs when a user selects a menu item or presses a keyboard shortcut attached to the command.
-
pending
- Type: boolean
-
This attribute is set to
true
if the tab is currently in the process of being restored by the session store service. Once the tab is restored, this attribute is removed. You can determine if a tab is being restored by checking to see ifhasAttribute("pending")
istrue
. If the user has turned on the "Don't load tabs until selected" preference, thepending
attribute is set on tabs until they get loaded.
pinned
- Type: boolean
- This attribute is set to
true
if the tab has been pinned (that is, if it's an app tab). Thetabbrowser
element'spinTab
andunpinTab
methods handle pinning and unpinning tabs.
-
selected
- Type: boolean
- This attribute is set to
true
if the tab is selected by default.
-
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 highertabindex
are later in the tab sequence.
unread
- Type: boolean
- This attribute is set to
true
if the tab is unread; that is, either it has not yet been selected during the current session, or has changed since the last time it was selected. This attribute is not present if the tab is not unread.
validate
- Type: one of the values below
- This attribute indicates whether to load the image from the cache or not. This would be useful if the images are stored remotely or you plan on swapping the image frequently. The following values are accepted, or leave out the attribute entirely for default handling:
-
always
- The image is always checked to see whether it should be reloaded.
never
- The image will be loaded from the cache if possible.
Properties
-
accessibleType
- Type: integer
- A value indicating the type of accessibility object for the element.
-
linkedPanel
- Type: id of a
tabpanel
element - Gets and sets the value of the
linkedpanel
attribute.
-
selected
- Type: boolean
-
This property's value is
true
if this element is selected, orfalse
if it is not. This property is read only. This property is available formenuitem
andmenuseparator
elements in Firefox 3.
-
value
- Type: string
-
Gets and sets the value of the
value
attribute. Fortextbox
and user editablemenulist
elements, the contents, as visible to the user, are read and set using theTextbox.value
and Menulist.value syntax.
Methods
Notes
Note: Prior to Gecko 1.9, disabling tabs fails; even while disabled, they still accept events.
Also, "unhiding" a tab leads to unpredictable ordering of the tabs. See bug 307088 and bug 261826. Use collapsed
instead of .
Related
- Elements
-
tabbox
,tabs
,tabpanels
,tabpanel
. - Interfaces
-
nsIAccessibleProvider
,nsIDOMXULSelectControlItemElement