hidden
attribute
contenteditable
content
attribute
designMode
getter
and
setter
inputmode
attribute
enterkeyhint
attribute
hidden
attribute
Support in all current engines.
All using the rules suggested in the Rendering section .
may have the content attribute set. The attribute is a . When specified on an element, it indicates that the element is not yet, or is no longer, directly relevant to the page's current state, or that it is being used to declare content to be reused by other parts of the page as opposed to being directly accessed by the user. User agents should not render elements that have the attribute specified. This requirement may be implemented indirectly through the style layer. For example, an HTML+CSS user agent could implement these requirementsBecause this attribute is typically implemented using CSS, it's also possible to override it using CSS. For instance, a rule that applies 'display: block' to all elements will cancel the effects of the
attribute. Authors therefore have to take care when writing their style sheets to make sure that the attribute is still styled as expected.In the following skeletal example, the attribute is used to hide the web game's main screen until the user logs in:
<h1>The Example Game</h1>
<section id="login">
<h2>Login</h2>
<form>
...
<!-- calls login() once the user's credentials have been checked -->
</form>
<script>
function login() {
// switch screens
document.getElementById('login').hidden = true;
document.getElementById('game').hidden = false;
}
</script>
</section>
<section id="game" hidden>
...
</section>
The
attribute must not be used to hide content that could legitimately be shown in another presentation. For example, it is incorrect to use to hide panels in a tabbed dialog, because the tabbed interface is merely a kind of overflow presentation — one could equally well just show all the form controls in one big page with a scrollbar. It is similarly incorrect to use this attribute to hide content just from one presentation — if something is marked , it is hidden from all presentations, including, for instance, screen readers.
Elements
that
are
not
themselves
for
attributes
of
and
elements
that
are
not
themselves
must
similarly
not
refer
to
elements
that
are
.
In
both
cases,
such
references
would
cause
user
confusion.
Elements and scripts may, however, refer to elements that are
in other contexts.For example, it would be incorrect to use the
attribute to link to a section marked with the attribute. If the content is not applicable or relevant, then there is no reason to link to it.It would be fine, however, to use the ARIA
attribute to refer to descriptions that are themselves . While hiding the descriptions implies that they are not useful alone, they could be written in such a way that they are useful in the specific context of being referenced from the elements that they describe.Similarly, a
element with the attribute could be used by a scripted graphics engine as an off-screen buffer, and a form control could refer to a hidden element using its attribute.Elements in a section hidden by the
attribute are still active, e.g. scripts and form controls in such sections still execute and submit respectively. Only their presentation to the user changes.Support in all current engines.
The
hidden
IDL
attribute
must
the
content
attribute
of
the
same
name.
This section does not define or create any content attribute named "inert". This section merely defines an abstract concept of inertness .
A node (in particular elements and text nodes) can be marked as inert . When a node is inert , then the user agent must act as if the node was absent for the purposes of targeting user interaction events, may ignore the node for the purposes of find-in-page , and may prevent the user from selecting text in that node. User agents should allow the user to override the restrictions on search and text selection, however.
For
example,
consider
a
page
that
consists
of
just
a
single
inert
paragraph
positioned
in
the
middle
of
a
body
.
If
a
user
moves
their
pointing
device
from
the
body
over
to
the
inert
paragraph
and
clicks
on
the
paragraph,
no
mouseover
event
would
be
fired,
and
the
mousemove
and
click
events
would
be
fired
on
the
body
element
rather
than
the
paragraph.
When a node is inert, it generally cannot be focused. Inert nodes that are commands will also get disabled.
While
a
browsing
context
container
is
marked
as
inert
,
its
nested
browsing
context
's
active
document
,
and
all
nodes
in
that
Document
,
must
be
marked
as
inert
.
An element is expressly inert if it is inert and its node document is not inert .
A
Document
document
is
blocked
by
a
modal
dialog
subject
if
subject
is
the
topmost
dialog
element
in
document
's
top
layer
.
While
document
is
so
blocked,
every
node
that
is
connected
to
document
,
with
the
exception
of
the
subject
element
and
its
shadow-including
descendants
,
must
be
marked
inert
.
(The
elements
excepted
by
this
paragraph
can
additionally
be
marked
inert
through
other
means;
being
part
of
a
modal
dialog
does
not
"protect"
a
node
from
being
marked
inert
.)
The
dialog
element's
showModal()
method
causes
this
mechanism
to
trigger,
by
adding
the
dialog
element
to
its
node
document
's
top
layer
.
To prevent abuse of certain APIs that could be annoying to users (e.g., opening popups or vibrating phones), user agents allow these APIs only when the user is actively interacting with the web page or has interacted with the page at least once. This "active interaction" state is maintained through the mechanisms defined in this section.
For
the
purpose
of
tracking
user
activation,
each
Window
W
has
a
last
activation
timestamp
.
This
is
a
number
indicating
the
last
time
W
got
an
activation
notification
.
It
corresponds
to
a
DOMHighResTimeStamp
value
except
for
two
cases:
positive
infinity
indicates
that
W
has
never
been
activated,
while
negative
infinity
indicates
that
a
user
activation-gated
API
has
consumed
the
last
user
activation
of
W
.
The
initial
value
is
positive
infinity.
A user agent also defines a transient activation duration , which is a constant number indicating how long a user activation is available for certain user activation-gated APIs (e.g., for opening popups).
The transient activation duration is expected be at most a few seconds, so that the user can possibly perceive the link between an interaction with the page and the page calling the activation-gated API.
These two values imply two boolean user activation states for W :
When the current high resolution time is greater than or equal to the last activation timestamp in W , W is said to have sticky activation .
This is W 's historical activation state, indicating whether the user has ever interacted in W . It starts false, then changes to true (and never changes back to false) when W gets the very first activation notification .
When the current high resolution time is greater than or equal to the last activation timestamp in W , and less than the last activation timestamp in W plus the transient activation duration , then W is said to have transient activation .
This is W 's current activation state, indicating whether the user has interacted in W recently. This starts with a false value, and remains true for a limited time after every activation notification W gets.
The transient activation state is considered expired if it becomes false because the transient activation duration time has elapsed since the last user activation. Note that it can become false even before the expiry time through an activation consumption .
When a user interaction in a browsing context B causes firing of an activation triggering input event in B 's active document D , the user agent must perform the following activation notification steps before dispatching the event:
Let browsingContexts be a list consisting of:
B ,
all ancestor browsing contexts of B , and
all the descendant browsing contexts of D that have active documents from the same origin as that of D .
Let
windows
be
the
list
of
Window
objects
constructed
by
taking
the
active
window
of
each
item
in
browsingContexts
.
For each window in windows , set window 's last activation timestamp to the current high resolution time .
An
activation
triggering
input
event
is
any
event
whose
isTrusted
attribute
is
true
and
whose
type
is
one
of:
The event set is inconsistent across major browsers. See issue #3849 .
Activation
consuming
APIs
defined
in
this
and
other
specifications
can
consume
user
activation
by
performing
the
following
steps,
given
a
Window
W
:
If W 's browsing context is null, then return.
Let top be W 's browsing context 's top-level browsing context .
Let browsingContexts be the list of the descendant browsing contexts of top 's active document .
Append top to browsingContexts .
Let
windows
be
the
list
of
Window
objects
constructed
by
taking
the
active
window
of
each
item
in
browsingContexts
.
For each window in windows , if window 's last activation timestamp is not positive infinity, then set window 's last activation timestamp to negative infinity.
The spec is not clear about how to traverse a tree of documents. See issue #5020 .
Note
the
asymmetry
in
the
sets
of
browsing
contexts
in
the
page
that
are
affected
by
an
activation
notification
vs
an
activation
consumption
:
an
activation
consumption
changes
(to
false)
the
transient
activation
states
for
all
browsing
contexts
in
the
page,
but
an
activation
notification
changes
(to
true)
the
states
for
a
subset
of
those
browsing
contexts.
The
exhaustive
nature
of
consumption
here
is
deliberate:
it
prevents
malicious
sites
from
making
multiple
calls
to
an
activation
consuming
API
from
a
single
user
activation
(possibly
by
exploiting
a
deep
hierarchy
of
iframe
s).
APIs that are dependent on user activation are classified into three different levels. The levels are as follows, sorted by their "strength of dependence" on user activation (from weakest to strongest):
These APIs require the sticky activation state to be true, so they are blocked until the very first user activation.
These APIs require the transient activation state to be true, but they don't consume it, so multiple calls are allowed per user activation until the transient state expires .
These APIs require the transient activation state to be true, and they consume user activation in each call to prevent multiple calls per user activation.
Certain
elements
in
HTML
have
an
activation
behavior
,
which
means
that
the
user
can
activate
them.
This
is
always
caused
by
a
click
event.
The
user
agent
should
allow
the
user
to
manually
trigger
elements
that
have
an
activation
behavior
,
for
instance
using
keyboard
or
voice
input,
or
through
mouse
clicks.
When
the
user
triggers
an
element
with
a
defined
activation
behavior
in
a
manner
other
than
clicking
it,
the
default
action
of
the
interaction
event
must
be
to
fire
a
click
event
at
the
element.
click
()
Acts as if the element was clicked.
Each element has an associated click in progress flag , which is initially unset.
The
click()
method
must
run
the
following
steps:
If this element is a form control that is disabled , then return.
If this element's click in progress flag is set, then return.
Set this element's click in progress flag .
Fire
a
synthetic
mouse
event
named
click
at
this
element,
with
the
not
trusted
flag
set.
Unset this element's click in progress flag .
This section is non-normative.
An HTML user interface typically consists of multiple interactive widgets, such as form controls, scrollable regions, links, dialog boxes, browser tabs, and so forth. These widgets form a hierarchy, with some (e.g. browser tabs, dialog boxes) containing others (e.g. links, form controls).
When interacting with an interface using a keyboard, key input is channeled from the system, through the hierarchy of interactive widgets, to an active widget, which is said to be focused .
Consider an HTML application running in a browser tab running in a graphical environment. Suppose this application had a page with some text controls and links, and was currently showing a modal dialog, which itself had a text control and a button.
The hierarchy of focusable widgets, in this scenario, would include the browser window, which would have, amongst its children, the browser tab containing the HTML application. The tab itself would have as its children the various links and text controls, as well as the dialog. The dialog itself would have as its children the text control and the button.
If the widget with focus in this example was the text control in the dialog box, then key input would be channeled from the graphical system to ① the web browser, then to ② the tab, then to ③ the dialog, and finally to ④ the text control.
Keyboard events are always targeted at this focused element.
The term focusable area is used to refer to regions of the interface that can become the target of keyboard input. Focusable areas can be elements, parts of elements, or other regions managed by the user agent.
Each
focusable
area
has
a
DOM
anchor
,
which
is
a
Node
object
that
represents
the
position
of
the
focusable
area
in
the
DOM.
(When
the
focusable
area
is
itself
a
Node
,
it
is
its
own
DOM
anchor
.)
The
DOM
anchor
is
used
in
some
APIs
as
a
substitute
for
the
focusable
area
when
there
is
no
other
DOM
object
to
represent
the
focusable
area
.
The following table describes what objects can be focusable areas . The cells in the left column describe objects that can be focusable areas ; the cells in the right column describe the DOM anchors for those elements. (The cells that span both columns are non-normative examples.)
Focusable area | DOM anchor |
---|---|
Examples | |
Elements
that
meet
all
the
following
criteria:
| The element itself. |
| |
The
shapes
of
area
elements
in
an
image
map
associated
with
an
img
element
that
is
being
rendered
and
is
not
expressly
inert
.
|
The
img
element.
|
In
the
following
example,
the
| |
The user-agent provided subwidgets of elements that are being rendered and are not actually disabled or expressly inert . | The element for which the focusable area is a subwidget. |
The
controls
in
the
user
interface
for
a
| |
The scrollable regions of elements that are being rendered and are not expressly inert . | The element for which the box that the scrollable region scrolls was created. |
The CSS 'overflow' property's 'scroll' value typically creates a scrollable region. | |
The
viewport
of
a
Document
that
has
a
non-null
browsing
context
and
is
not
inert
.
|
The
Document
for
which
the
viewport
was
created.
|
The
contents
of
an
| |
Any other element or part of an element determined by the user agent to be a focusable area, especially to aid with accessibility or to better match platform conventions. | The element. |
A user agent could make all list item bullets sequentially focusable , so that a user can more easily navigate lists.
Similarly,
a
user
agent
could
make
all
elements
with
|
A
browsing
context
container
(e.g.
an
iframe
)
is
a
focusable
area
,
but
key
events
routed
to
a
browsing
context
container
get
immediately
routed
to
its
nested
browsing
context
's
active
document
.
Similarly,
in
sequential
focus
navigation
a
browsing
context
container
essentially
acts
merely
as
a
placeholder
for
its
nested
browsing
context
's
active
document
.
One
focusable
area
in
each
Document
is
designated
the
focused
area
of
the
document
.
Which
control
is
so
designated
changes
over
time,
based
on
algorithms
in
this
specification.
The currently focused area of a top-level browsing context topLevelBC at any particular time is the focusable area returned by this algorithm:
Let candidate be topLevelBC 's active document .
While candidate 's focused area is a browsing context container with a non-null nested browsing context : set candidate to the active document of that browsing context container 's nested browsing context .
If candidate 's focused area is non-null, set candidate to candidate 's focused area .
Return candidate .
An element that is the DOM anchor of a focusable area is said to gain focus when that focusable area becomes the currently focused area of a top-level browsing context . When an element is the DOM anchor of a focusable area of the currently focused area of a top-level browsing context , it is focused .
The focus chain of a focusable area subject is the ordered list constructed as follows:
Let current object be subject .
Let output be an empty list.
Loop : Append current object to output .
If
current
object
is
an
area
element's
shape,
append
that
area
element
to
output
.
Otherwise, if current object is a focusable area whose DOM anchor is an element that is not current object itself, append that DOM anchor element to output .
If
current
object
is
a
Document
whose
browsing
context
is
a
child
browsing
context
,
then
set
current
object
to
current
object
's
browsing
context
's
container
and
return
to
the
step
labeled
loop
.
Return output .
The
chain
starts
with
subject
and
(if
subject
is
or
can
be
the
currently
focused
area
of
a
top-level
browsing
context
)
continues
up
the
focus
hierarchy
up
to
the
Document
of
the
top-level
browsing
context
.
All elements that are focusable areas are said to be focusable .
There are two special types of focusability for focusable areas :
A
focusable
area
is
said
to
be
sequentially
focusable
if
it
is
included
in
its
Document
's
sequential
focus
navigation
order
and
the
user
agent
determines
that
it
is
sequentially
focusable.
A focusable area is said to be click focusable if the user agent determines that it is click focusable. User agents should consider focusable areas with non-null tabindex values to be click focusable.
Elements which are not focusable are not focusable areas , and thus not sequentially focusable and not click focusable .
Being
focusable
is
a
statement
about
whether
an
element
can
be
focused
programmatically,
e.g.
via
the
focus()
method
or
autofocus
attribute.
In
contrast,
sequentially
focusable
and
click
focusable
govern
how
the
user
agent
responds
to
user
interaction:
respectively,
to
sequential
focus
navigation
and
as
activation
behavior
.
The
user
agent
might
determine
that
an
element
is
not
sequentially
focusable
even
if
it
is
focusable
and
is
included
in
its
Document
's
sequential
focus
navigation
order
,
according
to
user
preferences.
For
example,
macOS
users
can
set
the
user
agent
to
skip
non-form
control
elements,
or
can
skip
links
when
doing
sequential
focus
navigation
with
just
the
Tab
key
(as
opposed
to
using
both
the
Option
and
Tab
keys).
Similarly, the user agent might determine that an element is not click focusable even if it is focusable . For example, in some user agents, clicking on a non-editable form control does not focus it, i.e. the user agent has determined that such controls are not click focusable.
Thus, an element can be focusable , but neither sequentially focusable nor click focusable . For example, in some user agents, a non-editable form-control with a negative-integer tabindex value would not be focusable via user interaction, only via programmatic APIs.
When
a
user
activates
a
click
focusable
focusable
area
,
the
user
agent
must
run
the
focusing
steps
on
the
focusable
area
with
focus
trigger
set
to
"
click
".
Note
that
focusing
is
not
an
activation
behavior
,
i.e.
calling
the
click()
method
on
an
element
or
dispatching
a
synthetic
click
event
on
it
won't
cause
the
element
to
get
focused.
A node is a focus navigation scope owner if it is a document , a shadow host or a slot .
Each focus navigation scope owner has a focus navigation scope , which is a list of elements. Its contents are determined as follows:
Every element element has an associated focus navigation owner , which is either null or a focus navigation scope owner . It is determined by the following algorithm:
If element 's parent is null, then return null.
If element 's parent is a shadow host , then return element 's assigned slot .
If element 's parent is a shadow root , then return the parent's host .
If element 's parent is the document element , then return the parent's node document .
Return element 's parent's associated focus navigation owner .
Then, the contents of a given focus navigation scope owner owner 's focus navigation scope are all elements whose associated focus navigation owner is owner .
The order of elements within a focus navigation scope does not impact any of the algorithms in this specification. Ordering only becomes important for the tabindex-ordered focus navigation scope and flattened tabindex-ordered focus navigation scope concepts defined below.
A tabindex-ordered focus navigation scope is a list of focusable areas and focus navigation scope owners . Every focus navigation scope owner owner has tabindex-ordered focus navigation scope , whose contents are determined as follows:
It contains all elements in owner 's focus navigation scope that are themselves focus navigation scope owners , except the elements whose tabindex value is a negative integer.
It contains all of the focusable areas whose DOM anchor is an element in owner 's focus navigation scope , except the focusable areas whose tabindex value is a negative integer.
The order within a tabindex-ordered focus navigation scope is determined by each element's tabindex value , as described in the section below.
The rules there do not give a precise ordering, as they are composed mostly of "should" statements and relative orderings.
A flattened tabindex-ordered focus navigation scope is a list of focusable areas . Every focus navigation scope owner owner owns a distinct flattened tabindex-ordered focus navigation scope , whose contents are determined by the following algorithm:
Let result be a clone of owner 's tabindex-ordered focus navigation scope .
For each item of result :
If item is not a focus navigation scope owner , then continue .
If item is not a focusable area , then replace item with all of the items in item 's flattened tabindex-ordered focus navigation scope .
Otherwise, insert the contents of item 's flattened tabindex-ordered focus navigation scope after item .
tabindex
attribute
Support in all current engines.
The
tabindex
content
attribute
allows
authors
to
make
an
element
and
regions
that
have
the
element
as
its
DOM
anchor
be
focusable
areas
,
allow
or
prevent
them
from
being
sequentially
focusable
,
and
determine
their
relative
ordering
for
sequential
focus
navigation
.
The name "tab index" comes from the common use of the Tab key to navigate through the focusable elements. The term "tabbing" refers to moving forward through sequentially focusable focusable areas .
The
tabindex
attribute,
if
specified,
must
have
a
value
that
is
a
valid
integer
.
Positive
numbers
specify
the
relative
position
of
the
element's
focusable
areas
in
the
sequential
focus
navigation
order
,
and
negative
numbers
indicate
that
the
control
is
not
sequentially
focusable
.
Developers
should
use
caution
when
using
values
other
than
0
or
−1
for
their
tabindex
attributes
as
this
is
complicated
to
do
correctly.
The
following
provides
a
non-normative
summary
of
the
behaviors
of
the
possible
tabindex
attribute
values.
The
below
processing
model
gives
the
more
precise
rules.
tabindex
attribute
value
come
later.
Note
that
the
tabindex
attribute
cannot
be
used
to
make
an
element
non-focusable.
The
only
way
a
page
author
can
do
that
is
by
disabling
the
element,
or
making
it
inert
.
The
tabindex
value
of
an
element
is
the
value
of
its
tabindex
attribute,
parsed
using
the
rules
for
parsing
integers
.
If
parsing
fails
or
the
attribute
is
not
specified,
then
the
tabindex
value
is
null.
The tabindex value of a focusable area is the tabindex value of its DOM anchor .
The tabindex value of an element must be interpreted as follows:
The user agent should follow platform conventions to determine if the element should be considered as a focusable area and if so, whether the element and any focusable areas that have the element as their DOM anchor are sequentially focusable , and if so, what their relative position in their tabindex-ordered focus navigation scope is to be. If the element is a focus navigation scope owner , it must be included in its tabindex-ordered focus navigation scope even if it is not a focusable area .
The relative ordering within a tabindex-ordered focus navigation scope for elements and focusable areas that belong to the same focus navigation scope and whose tabindex value is null should be in shadow-including tree order .
Modulo platform conventions, it is suggested that the following elements should be considered as focusable areas and be sequentially focusable :
a
elements
that
have
an
href
attribute
link
elements
that
have
an
href
attribute
button
elements
input
elements
whose
type
attribute
are
not
in
the
state
select
elements
textarea
elements
summary
elements
that
are
the
first
summary
element
child
of
a
details
element
draggable
attribute
set,
if
that
would
enable
the
user
agent
to
allow
the
user
to
begin
a
drag
operations
for
those
elements
without
the
use
of
a
pointing
device
The user agent must consider the element as a focusable area , but should omit the element from any tabindex-ordered focus navigation scope .
One
valid
reason
to
ignore
the
requirement
that
sequential
focus
navigation
not
allow
the
author
to
lead
to
the
element
would
be
if
the
user's
only
mechanism
for
moving
the
focus
is
sequential
focus
navigation.
For
instance,
a
keyboard-only
user
would
be
unable
to
click
on
a
text
control
with
a
negative
tabindex
,
so
that
user's
user
agent
would
be
well
justified
in
allowing
the
user
to
tab
to
the
control
regardless.
The user agent must allow the element to be considered as a focusable area and should allow the element and any focusable areas that have the element as their DOM anchor to be sequentially focusable .
The relative ordering within a tabindex-ordered focus navigation scope for elements and focusable areas that belong to the same focus navigation scope and whose tabindex value is zero should be in shadow-including tree order .
The user agent must allow the element to be considered as a focusable area and should allow the element and any focusable areas that have the element as their DOM anchor to be sequentially focusable , and should place the element — referenced as candidate below — and the aforementioned focusable areas in the tabindex-ordered focus navigation scope where the element is a part of so that, relative to other elements and focusable areas that belong to the same focus navigation scope , they are:
tabindex
attribute
has
been
omitted
or
whose
value,
when
parsed,
returns
an
error,
tabindex
attribute
has
a
value
equal
to
or
less
than
zero,
tabindex
attribute
has
a
value
greater
than
zero
but
less
than
the
value
of
the
tabindex
attribute
on
candidate
,
tabindex
attribute
has
a
value
equal
to
the
value
of
the
tabindex
attribute
on
candidate
but
that
is
located
earlier
than
candidate
in
shadow-including
tree
order
,
tabindex
attribute
has
a
value
equal
to
the
value
of
the
tabindex
attribute
on
candidate
but
that
is
located
later
than
candidate
in
shadow-including
tree
order
,
and
tabindex
attribute
has
a
value
greater
than
the
value
of
the
tabindex
attribute
on
candidate
.
Support in all current engines.
The
tabIndex
IDL
attribute
must
reflect
the
value
of
the
tabindex
content
attribute.
The
default
value
is
0
if
the
element
is
an
a
,
area
,
button
,
frame
,
iframe
,
input
,
object
,
select
,
textarea
,
or
SVG
a
element,
or
is
a
summary
element
that
is
a
summary
for
its
parent
details
.
The
default
value
is
−1
otherwise.
The varying default value based on element type is a historical artifact.
To get the focusable area for a focus target that is either an element that is not a focusable area , or is a browsing context , given an optional string focus trigger , run the first matching set of steps from the following list:
area
element
with
one
or
more
shapes
that
are
focusable
areas
Return
the
shape
corresponding
to
the
first
img
element
in
tree
order
that
uses
the
image
map
to
which
the
area
element
belongs.
Return the element's first scrollable region, according to a pre-order, depth-first traversal of the flat tree . [CSSSCOPING]
Document
Return the browsing context 's active document .
Return the browsing context container 's nested browsing context 's active document .
Otherwise:
click
",
then
let
possible
focus
delegates
be
the
list
of
all
click
focusable
focusable
areas
whose
DOM
anchor
is
a
descendant
of
focus
target
in
the
flat
tree
.
For sequential focusability , the handling of shadow hosts and delegates focus is done when constructing the sequential focus navigation order . That is, the focusing steps will never be called on such shadow hosts as part of sequential focus navigation.
Return null.
The focusing steps for an object new focus target that is either a focusable area , or an element that is not a focusable area , or a browsing context , are as follows. They can optionally be run with a fallback target and a string focus trigger .
If new focus target is not a focusable area , then set new focus target to the result of getting the focusable area for new focus target , given focus trigger if it was passed.
If new focus target is null, then:
If no fallback target was specified, then return.
Otherwise, set new focus target to the fallback target .
If new focus target is a browsing context container with non-null nested browsing context , then set new focus target to the nested browsing context 's active document , and redo this step.
If new focus target is a focusable area and its DOM anchor is inert , then return.
If new focus target is the currently focused area of a top-level browsing context , then return.
Let old chain be the focus chain of the currently focused area of the top-level browsing context in which new focus target finds itself.
Let new chain be the focus chain of new focus target .
Run the focus update steps with old chain , new chain , and new focus target respectively.
User agents must immediately run the focusing steps for a focusable area or browsing context candidate whenever the user attempts to move the focus to candidate .
The unfocusing steps for an object old focus target that is either a focusable area or an element that is not a focusable area are as follows:
If old focus target is inert , then return.
If
old
focus
target
is
an
area
element
and
one
of
its
shapes
is
the
currently
focused
area
of
a
top-level
browsing
context
,
or,
if
old
focus
target
is
an
element
with
one
or
more
scrollable
regions,
and
one
of
them
is
the
currently
focused
area
of
a
top-level
browsing
context
,
then
let
old
focus
target
be
that
currently
focused
area
of
a
top-level
browsing
context
.
Let old chain be the focus chain of the currently focused area of a top-level browsing context .
If old focus target is not one of the entries in old chain , then return.
If
old
focus
target
is
a
focusable
area
,
then
let
new
focus
target
be
its
Document
's
viewport
.
Otherwise, let new focus target be null.
If new focus target is not null, then run the focusing steps for new focus target .
When the currently focused area of a top-level browsing context is somehow unfocused without another element being explicitly focused in its stead, the user agent must immediately run the unfocusing steps for that object.
The unfocusing steps do not always result in the focus changing, even when applied to the currently focused area of a top-level browsing context . For example, if the currently focused area of a top-level browsing context is a viewport , then it will usually keep its focus regardless until another focusable area is explicitly focused with the focusing steps .
Focus
fixup
rule
:
When
the
designated
focused
area
of
the
document
is
removed
from
that
Document
in
some
way
(e.g.
it
stops
being
a
focusable
area
,
it
is
removed
from
the
DOM,
it
becomes
expressly
inert
,
etc.),
designate
the
Document
's
viewport
to
be
the
new
focused
area
of
the
document
.
For
example,
this
might
happen
because
an
element
is
removed
from
its
Document
,
or
has
a
attribute
added.
It
might
also
happen
to
an
input
element
when
the
element
gets
disabled
.
In
a
Document
whose
focused
area
is
a
button
element,
removing,
disabling,
or
hiding
that
button
would
cause
the
page's
new
focused
area
to
be
the
viewport
of
the
Document
.
This
would,
in
turn,
be
reflected
through
the
activeElement
API
as
the
body
element
.
The focus update steps , given an old chain , a new chain , and a new focus target respectively, are as follows:
If the last entry in old chain and the last entry in new chain are the same, pop the last entry from old chain and the last entry from new chain and redo this step.
For each entry entry in old chain , in order, run these substeps:
If
entry
is
an
input
element,
and
the
change
event
applies
to
the
element,
and
the
element
does
not
have
a
defined
activation
behavior
,
and
the
user
has
changed
the
element's
value
or
its
list
of
selected
files
while
the
control
was
focused
without
committing
that
change
(such
that
it
is
different
to
what
it
was
when
the
control
was
first
focused),
then
fire
an
event
named
change
at
the
element,
with
the
bubbles
attribute
initialized
to
true.
If entry is an element, let blur event target be entry .
If
entry
is
a
Document
object,
let
blur
event
target
be
that
Document
object's
relevant
global
object
.
Otherwise, let blur event target be null.
If
entry
is
the
last
entry
in
old
chain
,
and
entry
is
an
Element
,
and
the
last
entry
in
new
chain
is
also
an
Element
,
then
let
related
blur
target
be
the
last
entry
in
new
chain
.
Otherwise,
let
related
blur
target
be
null.
If
blur
event
target
is
not
null,
fire
a
focus
event
named
blur
at
blur
event
target
,
with
related
blur
target
as
the
related
target.
In
some
cases,
e.g.
if
entry
is
an
area
element's
shape,
a
scrollable
region,
or
a
viewport
,
no
event
is
fired.
Apply any relevant platform-specific conventions for focusing new focus target . (For example, some platforms select the contents of a text control when that control is focused.)
For each entry entry in new chain , in reverse order, run these substeps:
If entry is a focusable area : designate entry as the focused area of the document .
If entry is an element, let focus event target be entry .
If
entry
is
a
Document
object,
let
focus
event
target
be
that
Document
object's
relevant
global
object
.
Otherwise, let focus event target be null.
If
entry
is
the
last
entry
in
new
chain
,
and
entry
is
an
Element
,
and
the
last
entry
in
old
chain
is
also
an
Element
,
then
let
related
focus
target
be
the
last
entry
in
old
chain
.
Otherwise,
let
related
focus
target
be
null.
If
focus
event
target
is
not
null,
fire
a
focus
event
named
focus
at
focus
event
target
,
with
related
focus
target
as
the
related
target.
In
some
cases,
e.g.
if
entry
is
an
area
element's
shape,
a
scrollable
region,
or
a
viewport
,
no
event
is
fired.
To
fire
a
focus
event
named
e
at
an
element
t
with
a
given
related
target
r
,
fire
an
event
named
e
at
t
,
using
FocusEvent
,
with
the
relatedTarget
attribute
initialized
to
r
,
the
view
attribute
initialized
to
t
's
node
document
's
relevant
global
object
,
and
the
composed
flag
set.
When a key event is to be routed in a top-level browsing context , the user agent must run the following steps:
Let target area be the currently focused area of the top-level browsing context .
If
target
area
is
a
focusable
area
,
let
target
node
be
target
area
's
DOM
anchor
.
Otherwise,
target
area
is
a
dialog
;
let
target
node
be
target
area
.
If
target
node
is
a
Document
that
has
a
body
element
,
then
let
target
node
be
the
body
element
of
that
Document
.
Otherwise,
if
target
node
is
a
Document
object
that
has
a
non-null
document
element
,
then
let
target
node
be
that
document
element
.
If target node is not inert , then:
It
is
possible
for
the
currently
focused
area
of
a
top-level
browsing
context
to
be
inert
,
for
example
if
a
modal
dialog
is
shown
,
and
then
that
dialog
element
is
made
inert
.
It
is
likely
to
be
the
result
of
a
logic
error
in
the
application,
though.
Let canHandle be the result of dispatching the key event at target node .
If
canHandle
is
true,
then
let
target
area
handle
the
key
event.
This
might
include
firing
a
click
event
at
target
node
.
The
has
focus
steps
,
given
a
Document
object
target
,
are
as
follows:
Let candidate be target 's top-level browsing context 's active document .
While true:
If candidate is target , then return true.
If the focused area of candidate is a browsing context container with a non-null nested browsing context , then set candidate to the active document of that browsing context container 's nested browsing context .
Otherwise, return false.
Each
Document
has
a
sequential
focus
navigation
order
,
which
orders
some
or
all
of
the
focusable
areas
in
the
Document
relative
to
each
other.
Its
contents
and
ordering
are
given
by
the
flattened
tabindex-ordered
focus
navigation
scope
of
the
Document
.
Per
the
rules
defining
the
flattened
tabindex-ordered
focus
navigation
scope
,
the
ordering
is
not
necessarily
related
to
the
tree
order
of
the
Document
.
If
a
focusable
area
is
omitted
from
the
sequential
focus
navigation
order
of
its
Document
,
then
it
is
unreachable
via
sequential
focus
navigation
.
There can also be a sequential focus navigation starting point . It is initially unset. The user agent may set it when the user indicates that it should be moved.
For example, the user agent could set it to the position of the user's click if the user clicks on the document contents.
User agents are required to set the sequential focus navigation starting point to the target element when navigating to a fragment .
When the user requests that focus move from the currently focused area of a top-level browsing context to the next or previous focusable area (e.g. as the default action of pressing the tab key), or when the user requests that focus sequentially move to a top-level browsing context in the first place (e.g. from the browser's location bar), the user agent must use the following algorithm:
Let starting point be the currently focused area of a top-level browsing context , if the user requested to move focus sequentially from there, or else the top-level browsing context itself, if the user instead requested to move focus from outside the top-level browsing context .
If there is a sequential focus navigation starting point defined and it is inside starting point , then let starting point be the sequential focus navigation starting point instead.
Let direction be forward if the user requested the next control, and backward if the user requested the previous control.
Typically, pressing tab requests the next control, and pressing shift + tab requests the previous control.
Loop
:
Let
selection
mechanism
be
sequential
if
the
starting
point
is
a
browsing
context
or
if
starting
point
is
in
its
Document
's
sequential
focus
navigation
order
.
Otherwise,
starting
point
is
not
in
its
Document
's
sequential
focus
navigation
order
;
let
selection
mechanism
be
DOM
.
Let candidate be the result of running the sequential navigation search algorithm with starting point , direction , and selection mechanism as the arguments.
If candidate is not null, then run the focusing steps for candidate and return.
Otherwise, unset the sequential focus navigation starting point .
If starting point is the top-level browsing context , or a focusable area in the top-level browsing context , the user agent should transfer focus to its own controls appropriately (if any), honouring direction , and then return.
For example, if direction is backward , then the last sequentially focusable control before the browser's rendering area would be the control to focus.
If the user agent has no sequentially focusable controls — a kiosk-mode browser, for instance — then the user agent may instead restart these steps with the starting point being the top-level browsing context itself.
Otherwise, starting point is a focusable area in a child browsing context . Set starting point to that child browsing context 's container and return to the step labeled loop .
The sequential navigation search algorithm consists of the following steps. This algorithm takes three arguments: starting point , direction , and selection mechanism .
Pick the appropriate cell from the following table, and follow the instructions in that cell.
The appropriate cell is the one that is from the column whose header describes direction and from the first row whose header describes starting point and selection mechanism .
direction is forward | direction is backward | |
---|---|---|
starting point is a browsing context | Let candidate be the first suitable sequentially focusable area in starting point 's active document , if any; or else null | Let candidate be the last suitable sequentially focusable area in starting point 's active document , if any; or else null |
selection mechanism is DOM | Let candidate be the first suitable sequentially focusable area in the home document following starting point , if any; or else null | Let candidate be the last suitable sequentially focusable area in the home document preceding starting point , if any; or else null |
selection mechanism is sequential | Let candidate be the first suitable sequentially focusable area in the home sequential focus navigation order following starting point , if any; or else null | Let candidate be the last suitable sequentially focusable area in the home sequential focus navigation order preceding starting point , if any; or else null |
A suitable sequentially focusable area is a focusable area whose DOM anchor is not inert and is sequentially focusable .
The
home
document
is
the
Document
to
which
starting
point
belongs.
The home sequential focus navigation order is the sequential focus navigation order to which starting point belongs.
The home sequential focus navigation order is the home document 's sequential focus navigation order , but is only used when the starting point is in that sequential focus navigation order (when it's not, selection mechanism will be DOM ).
If candidate is a browsing context container with a non-null nested browsing context , then let new candidate be the result of running the sequential navigation search algorithm with candidate 's nested browsing context as the first argument, direction as the second, and sequential as the third.
If new candidate is null, then let starting point be candidate , and return to the top of this algorithm. Otherwise, let candidate be new candidate .
Return candidate .
dictionary FocusOptions {
boolean preventScroll = false;
};
activeElement
Returns the deepest element in the document through which or to which key events are being routed. This is, roughly speaking, the focused element in the document.
For
the
purposes
of
this
API,
when
a
child
browsing
context
is
focused,
its
container
is
focused
in
the
parent
browsing
context
.
For
example,
if
the
user
moves
the
focus
to
a
text
control
in
an
iframe
,
the
iframe
is
the
element
returned
by
the
activeElement
API
in
the
iframe
's
node
document
.
Similarly, when the focused element is in a different node tree than documentOrShadowRoot , the element returned will be the host that's located in the same node tree as documentOrShadowRoot if documentOrShadowRoot is a shadow-including inclusive ancestor of the focused element, and null if not.
hasFocus
()
Returns true if key events are being routed through or to the document; otherwise, returns false. Roughly speaking, this corresponds to the document, or a document nested inside this one, being focused.
focus
()
Moves the focus to the window's browsing context , if any.
focus
([
{
preventScroll
:
true
}
])
Moves the focus to the element.
If the element is a browsing context container , moves the focus to its nested browsing context instead.
By
default,
this
method
also
scrolls
the
element
into
view.
Providing
the
preventScroll
option
and
setting
it
to
true
prevents
this
behavior.
blur
()
Moves
the
focus
to
the
viewport
.
Use
of
this
method
is
discouraged;
if
you
want
to
focus
the
viewport
,
call
the
focus()
method
on
the
Document
's
document
element
.
Do not use this method to hide the focus ring if you find the focus ring unsightly. Instead, use a CSS rule to override the 'outline' property, and provide a different way to show what element is focused. Be aware that if an alternative focusing style isn't made available, the page will be significantly less usable for people who primarily navigate pages using a keyboard, or those with reduced vision who use focus outlines to help them navigate the page.
For example, to hide the outline from links and instead use a yellow background to indicate focus, you could use:
:link:focus,
:visited:focus
{
outline:
none;
background:
yellow;
color:
black;
}
DocumentOrShadowRoot/activeElement
Support in all current engines.
The
activeElement
attribute's
getter
must
run
these
steps:
Let
candidate
be
the
DOM
anchor
of
the
focused
area
of
this
DocumentOrShadowRoot
's
node
document
.
Set
candidate
to
the
result
of
retargeting
candidate
against
this
DocumentOrShadowRoot
.
If
candidate
's
root
is
not
this
DocumentOrShadowRoot
,
then
return
null.
If
candidate
is
not
a
Document
object,
then
return
candidate
.
If candidate has a body element , then return that body element .
If candidate 's document element is non-null, then return that document element .
Return null.
Support in all current engines.
The
hasFocus()
method
on
the
Document
object,
when
invoked,
must
return
the
result
of
running
the
has
focus
steps
with
the
Document
object
as
the
argument.
Support in all current engines.
The
focus()
method,
when
invoked,
must
run
these
steps:
Let
current
be
this
Window
object's
browsing
context
.
If current is null, then return.
Run the focusing steps with current .
If current is a top-level browsing context , user agents are encouraged to trigger some sort of notification to indicate to the user that the page is attempting to gain focus.
Support in all current engines.
The
blur()
method,
when
invoked,
provides
a
hint
to
the
user
agent
that
the
script
believes
the
user
probably
is
not
currently
interested
in
the
contents
of
this
Window
object's
browsing
context
,
if
non-null,
but
that
the
contents
might
become
interesting
again
in
the
future.
User
agents
are
encouraged
to
ignore
calls
to
this
blur()
method
entirely.
Historically,
the
focus()
and
blur()
methods
actually
affected
the
system-level
focus
of
the
system
widget
(e.g.,
tab
or
window)
that
contained
the
browsing
context
,
but
hostile
sites
widely
abuse
this
behavior
to
the
user's
detriment.
Support in all current engines.
The
focus(
options
)
method
on
elements,
when
invoked,
must
run
the
following
steps:
If the element is marked as locked for focus , then return.
Mark the element as locked for focus .
Run the focusing steps for the element.
If
the
value
of
the
preventScroll
dictionary
member
of
options
is
false,
then
scroll
the
element
into
view
with
scroll
behavior
"
auto
",
block
flow
direction
position
set
to
an
implementation-defined
value,
and
inline
base
direction
position
set
to
an
implementation-defined
value.
Unmark the element as locked for focus .
Support in all current engines.
The
blur()
method,
when
invoked,
should
run
the
unfocusing
steps
for
the
element
on
which
the
method
was
called.
User
agents
may
selectively
or
uniformly
ignore
calls
to
this
method
for
usability
reasons.
For
example,
if
the
blur()
method
is
unwisely
being
used
to
remove
the
focus
ring
for
aesthetics
reasons,
the
page
would
become
unusable
by
keyboard
users.
Ignoring
calls
to
this
method
would
thus
allow
keyboard
users
to
interact
with
the
page.
autofocus
attribute
Support in all current engines.
The
autofocus
content
attribute
allows
the
author
to
indicate
that
an
element
is
to
be
focused
as
soon
as
the
page
is
loaded
or
as
soon
as
the
dialog
within
which
it
finds
itself
is
shown,
allowing
the
user
to
just
start
typing
without
having
to
manually
focus
the
main
element.
The
autofocus
attribute
is
a
boolean
attribute
.
An
element's
nearest
ancestor
autofocus
scoping
root
element
is
the
element
itself
if
the
element
is
a
dialog
element,
or
else
is
the
element's
nearest
ancestor
dialog
element,
if
any,
or
else
is
the
element's
last
inclusive
ancestor
element.
There
must
not
be
two
elements
with
the
same
nearest
ancestor
autofocus
scoping
root
element
that
both
have
the
autofocus
attribute
specified.
Each
Document
has
an
autofocus
candidates
list
,
initially
empty.
Each
Document
has
an
autofocus
processed
flag
boolean,
initially
false.
When
an
element
with
the
autofocus
attribute
specified
is
inserted
into
a
document
,
run
the
following
steps:
If the user has indicated (for example, by starting to type in a form control) that they do not wish focus to be changed, then optionally return.
Let target be the element's node document .
If target 's browsing context is null, then return.
If target 's active sandboxing flag set has the sandboxed automatic features browsing context flag , then return.
Let topDocument be the active document of target 's browsing context 's top-level browsing context .
If target 's origin is not the same as the origin of topDocument , then return.
If topDocument 's autofocus processed flag is false, then remove the element from topDocument 's autofocus candidates , and append the element to topDocument 's autofocus candidates .
We do not check if an element is a focusable area before storing it in the autofocus candidates list, because even if it is not a focusable area when it is inserted, it could become one by the time flush autofocus candidates sees it.
To flush autofocus candidates for a document topDocument , run these steps:
If topDocument 's autofocus processed flag is true, then return.
Let candidates be topDocument 's autofocus candidates .
If candidates is empty , then return.
If topDocument 's focused area is not topDocument itself, or topDocument 's URL 's fragment is not empty, then:
Empty candidates .
Set topDocument 's autofocus processed flag to true.
Return.
While candidates is not empty :
Let element be candidates [0].
Let doc be element 's node document .
If doc is not fully active , then remove element from candidates , and continue .
If doc 's browsing context 's top-level browsing context is not same as topDocument 's browsing context , then remove element from candidates , and continue .
If doc 's script-blocking style sheet counter is greater than 0, then return.
In this case, element is the currently-best candidate, but doc is not ready for autofocusing. We'll try again next time flush autofocus candidates is called.
Remove element from candidates .
Let inclusiveAncestorDocuments be a list consisting of doc , plus the active documents of each of doc 's browsing context 's ancestor browsing contexts .
If
URL
's
fragment
of
any
Document
in
inclusiveAncestorDocuments
is
not
empty,
then
continue
.
Let target be element .
If target is not a focusable area , then set target to the result of getting the focusable area for target .
Autofocus
candidates
can
contain
elements
which
are
not
focusable
areas
.
In
addition
to
the
special
cases
handled
in
the
get
the
focusable
area
algorithm,
this
can
happen
because
a
non-
focusable
area
element
with
an
autofocus
attribute
was
inserted
into
a
document
and
it
never
became
focusable,
or
because
the
element
was
focusable
but
its
status
changed
while
it
was
stored
in
autofocus
candidates
.
If target is not null, then:
Empty candidates .
Set topDocument 's autofocus processed flag to true.
Run the focusing steps for target .
This
handles
the
automatic
focusing
during
document
load.
The
show()
and
showModal()
methods
of
dialog
elements
also
processes
the
autofocus
attribute.
Focusing the element does not imply that the user agent has to focus the browser window if it has lost focus.
Support in all current engines.
The
autofocus
IDL
attribute
must
reflect
the
content
attribute
of
the
same
name.
In the following snippet, the text control would be focused when the document was loaded.
<input maxlength="256" name="q" value="" autofocus>
<input
type="submit"
value="Search">
The
autofocus
attribute
applies
to
all
elements,
not
just
to
form
controls.
This
allows
examples
such
as
the
following:
<div
contenteditable
autofocus>Edit
<strong>me!</strong><div>
This section is non-normative.
Each
element
that
can
be
activated
or
focused
can
be
assigned
a
single
key
combination
to
activate
it,
using
the
accesskey
attribute.
The
exact
shortcut
is
determined
by
the
user
agent,
based
on
information
about
the
user's
keyboard,
what
keyboard
shortcuts
already
exist
on
the
platform,
and
what
other
shortcuts
have
been
specified
on
the
page,
using
the
information
provided
in
the
accesskey
attribute
as
a
guide.
In
order
to
ensure
that
a
relevant
keyboard
shortcut
is
available
on
a
wide
variety
of
input
devices,
the
author
can
provide
a
number
of
alternatives
in
the
accesskey
attribute.
Each alternative consists of a single character, such as a letter or digit.
User
agents
can
provide
users
with
a
list
of
the
keyboard
shortcuts,
but
authors
are
encouraged
to
do
so
also.
The
accessKeyLabel
IDL
attribute
returns
a
string
representing
the
actual
key
combination
assigned
by
the
user
agent.
In this example, an author has provided a button that can be invoked using a shortcut key. To support full keyboards, the author has provided "C" as a possible key. To support devices equipped only with numeric keypads, the author has provided "1" as another possibly key.
<input type=button value=Collect onclick="collect()"
accesskey="C
1"
id=c>
To tell the user what the shortcut key is, the author has this script here opted to explicitly add the key combination to the button's label:
function addShortcutKeyLabel(button) {
if (button.accessKeyLabel != '')
button.value += ' (' + button.accessKeyLabel + ')';
}
addShortcutKeyLabel(document.getElementById('c'));
Browsers on different platforms will show different labels, even for the same key combination, based on the convention prevalent on that platform. For example, if the key combination is the Control key, the Shift key, and the letter C, a Windows browser might display " Ctrl+Shift+C ", whereas a Mac browser might display " ^⇧C ", while an Emacs browser might just display " C-C ". Similarly, if the key combination is the Alt key and the Escape key, Windows might use " Alt+Esc ", Mac might use " ⌥⎋ ", and an Emacs browser might use " M-ESC " or " ESC ESC ".
In
general,
therefore,
it
is
unwise
to
attempt
to
parse
the
value
returned
from
the
accessKeyLabel
IDL
attribute.
accesskey
attribute
Support in all current engines.
All
HTML
elements
may
have
the
accesskey
content
attribute
set.
The
accesskey
attribute's
value
is
used
by
the
user
agent
as
a
guide
for
creating
a
keyboard
shortcut
that
activates
or
focuses
the
element.
If specified, the value must be an ordered set of unique space-separated tokens none of which are identical to another token and each of which must be exactly one code point in length.
In the following example, a variety of links are given with access keys so that keyboard users familiar with the site can more quickly navigate to the relevant pages:
<nav>
<p>
<a title="Consortium Activities" accesskey="A" href="/Consortium/activities">Activities</a> |
<a title="Technical Reports and Recommendations" accesskey="T" href="/TR/">Technical Reports</a> |
<a title="Alphabetical Site Index" accesskey="S" href="/Consortium/siteindex">Site Index</a> |
<a title="About This Site" accesskey="B" href="/Consortium/">About Consortium</a> |
<a title="Contact Consortium" accesskey="C" href="/Consortium/contact">Contact</a>
</p>
</nav>
In the following example, the search field is given two possible access keys, "s" and "0" (in that order). A user agent on a device with a full keyboard might pick Ctrl + Alt + S as the shortcut key, while a user agent on a small device with just a numeric keypad might pick just the plain unadorned key 0 :
<form action="/search">
<label>Search: <input type="search" name="q" accesskey="s 0"></label>
<input type="submit">
</form>
In the following example, a button has possible access keys described. A script then tries to update the button's label to advertise the key combination the user agent selected.
<input type=submit accesskey="N @ 1" value="Compose">
...
<script>
function labelButton(button) {
if (button.accessKeyLabel)
button.value += ' (' + button.accessKeyLabel + ')';
}
var inputs = document.getElementsByTagName('input');
for (var i = 0; i < inputs.length; i += 1) {
if (inputs[i].type == "submit")
labelButton(inputs[i]);
}
</script>
On one user agent, the button's label might become " Compose (⌘N) ". On another, it might become " Compose (Alt+⇧+1) ". If the user agent doesn't assign a key, it will be just " Compose ". The exact string depends on what the assigned access key is, and on how the user agent represents that key combination.
An
element's
assigned
access
key
is
a
key
combination
derived
from
the
element's
accesskey
content
attribute.
Initially,
an
element
must
not
have
an
assigned
access
key
.
Whenever
an
element's
accesskey
attribute
is
set,
changed,
or
removed,
the
user
agent
must
update
the
element's
assigned
access
key
by
running
the
following
steps:
If
the
element
has
no
accesskey
attribute,
then
skip
to
the
fallback
step
below.
Otherwise, split the attribute's value on ASCII whitespace , and let keys be the resulting tokens.
For each value in keys in turn, in the order the tokens appeared in the attribute's value, run the following substeps:
If the value is not a string exactly one code point in length, then skip the remainder of these steps for this value.
If the value does not correspond to a key on the system's keyboard, then skip the remainder of these steps for this value.
If
the
user
agent
can
find
a
mix
of
zero
or
more
modifier
keys
that,
combined
with
the
key
that
corresponds
to
the
value
given
in
the
attribute,
can
be
used
as
the
access
key,
then
the
user
agent
may
assign
that
combination
of
keys
as
the
element's
assigned
access
key
and
return.
Fallback : Optionally, the user agent may assign a key combination of its choosing as the element's assigned access key and then return.
If this step is reached, the element has no assigned access key .
Once
a
user
agent
has
selected
and
assigned
an
access
key
for
an
element,
the
user
agent
should
not
change
the
element's
assigned
access
key
unless
the
accesskey
content
attribute
is
changed
or
the
element
is
moved
to
another
Document
.
When the user presses the key combination corresponding to the assigned access key for an element, if the element defines a command , the command's facet is false (visible), the command's Disabled State facet is also false (enabled), the element is in a document that has a non-null browsing context , and neither the element nor any of its ancestors has a attribute specified, then the user agent must trigger the Action of the command.
User
agents
might
expose
elements
that
have
an
accesskey
attribute
in
other
ways
as
well,
e.g.
in
a
menu
displayed
in
response
to
a
specific
key
combination.
The
accessKey
IDL
attribute
must
reflect
the
accesskey
content
attribute.
Support in one engine only.
The
accessKeyLabel
IDL
attribute
must
return
a
string
that
represents
the
element's
assigned
access
key
,
if
any.
If
the
element
does
not
have
one,
then
the
IDL
attribute
must
return
the
empty
string.
contenteditable
content
attribute
Support in all current engines.
interface mixin ElementContentEditable {
[CEReactions] attribute DOMString contentEditable;
[CEReactions] attribute DOMString enterKeyHint;
readonly attribute boolean isContentEditable;
[CEReactions] attribute DOMString inputMode;
};
Global_attributes/contenteditable
Support in all current engines.
The
contenteditable
content
attribute
is
an
enumerated
attribute
whose
keywords
are
the
empty
string,
true
,
and
false
.
The
empty
string
and
the
true
keyword
map
to
the
true
state.
The
false
keyword
maps
to
the
false
state.
In
addition,
there
is
a
third
state,
the
inherit
state,
which
is
the
missing
value
default
and
the
invalid
value
default
.
The true state indicates that the element is editable. The inherit state indicates that the element is editable if its parent is. The false state indicates that the element is not editable.
For
example,
consider
a
page
that
has
a
form
and
a
textarea
to
publish
a
new
article,
where
the
user
is
expected
to
write
the
article
using
HTML:
<form method=POST>
<fieldset>
<legend>New article</legend>
<textarea name=article><p>Hello world.</p></textarea>
</fieldset>
<p><button>Publish</button></p>
</form>
When
scripting
is
enabled,
the
textarea
element
could
be
replaced
with
a
rich
text
control
instead,
using
the
contenteditable
attribute:
<form method=POST>
<fieldset>
<legend>New article</legend>
<textarea id=textarea name=article><p>Hello world.</p></textarea>
<div id=div style="white-space: pre-wrap" hidden><p>Hello world.</p></div>
<script>
let textarea = document.getElementById("textarea");
let div = document.getElementById("div");
textarea.hidden = true;
div.hidden = false;
div.contentEditable = "true";
div.oninput = (e) => {
textarea.value = div.innerHTML;
};
</script>
</fieldset>
<p><button>Publish</button></p>
</form>
Features
to
enable,
e.g.,
inserting
links,
can
be
implemented
using
the
document.execCommand()
API,
or
using
Selection
APIs
and
other
DOM
APIs.
[EXECCOMMAND]
[SELECTION]
[DOM]
The
contenteditable
attribute
can
also
be
used
to
great
effect:
<!doctype html>
<html lang=en>
<title>Live CSS editing!</title>
<style style=white-space:pre contenteditable>
html { margin:.2em; font-size:2em; color:lime; background:purple }
head, title, style { display:block }
body { display:none }
</style>
contentEditable
[
=
value
]
Returns
"
true
",
"
false
",
or
"
inherit
",
based
on
the
state
of
the
contenteditable
attribute.
Can be set, to change that state.
Throws
a
"
SyntaxError
"
DOMException
if
the
new
value
isn't
one
of
those
strings.
isContentEditable
Returns true if the element is editable; otherwise, returns false.
The
contentEditable
IDL
attribute,
on
getting,
must
return
the
string
"
true
"
if
the
content
attribute
is
set
to
the
true
state,
"
false
"
if
the
content
attribute
is
set
to
the
false
state,
and
"
inherit
"
otherwise.
On
setting,
if
the
new
value
is
an
ASCII
case-insensitive
match
for
the
string
"
inherit
"
then
the
content
attribute
must
be
removed,
if
the
new
value
is
an
ASCII
case-insensitive
match
for
the
string
"
true
"
then
the
content
attribute
must
be
set
to
the
string
"
true
",
if
the
new
value
is
an
ASCII
case-insensitive
match
for
the
string
"
false
"
then
the
content
attribute
must
be
set
to
the
string
"
false
",
and
otherwise
the
attribute
setter
must
throw
a
"
SyntaxError
"
DOMException
.
Support in all current engines.
The
isContentEditable
IDL
attribute,
on
getting,
must
return
true
if
the
element
is
either
an
editing
host
or
editable
,
and
false
otherwise.
designMode
getter
and
setter
Support in all current engines.
designMode
[
=
value
]
Returns
"
on
"
if
the
document
is
editable,
and
"
off
"
if
it
isn't.
Can be set, to change the document's current state. This focuses the document and resets the selection in that document.
Document
objects
have
an
associated
design
mode
enabled
,
which
is
a
boolean.
It
is
initially
false.
The
designMode
getter
steps
are
to
return
"
on
"
if
this
's
design
mode
enabled
is
true;
otherwise
"
off
".
The
designMode
setter
steps
are:
Let value be the given value, converted to ASCII lowercase .
If
value
is
"
on
"
and
this
's
design
mode
enabled
is
false,
then:
Set this 's design mode enabled to true.
Reset this 's active range 's start and end boundary points to be at the start of this .
Run the focusing steps for this 's document element , if non-null.
If
value
is
"
off
",
then
set
this
's
design
mode
enabled
to
false.
Authors are encouraged to set the 'white-space' property on editing hosts and on markup that was originally created through these editing mechanisms to the value 'pre-wrap'. Default HTML whitespace handling is not well suited to WYSIWYG editing, and line wrapping will not work correctly in some corner cases if 'white-space' is left at its default value.
As an example of problems that occur if the default 'normal' value is used instead, consider the case of the user typing " yellow␣␣ball ", with two spaces (here represented by "␣") between the words. With the editing rules in place for the default value of 'white-space' ('normal'), the resulting markup will either consist of " yellow ball " or " yellow ball "; i.e., there will be a non-breaking space between the two words in addition to the regular space. This is necessary because the 'normal' value for 'white-space' requires adjacent regular spaces to be collapsed together.
In the former case, " yellow⍽ " might wrap to the next line ("⍽" being used here to represent a non-breaking space) even though " yellow " alone might fit at the end of the line; in the latter case, " ⍽ball ", if wrapped to the start of the line, would have visible indentation from the non-breaking space.
When 'white-space' is set to 'pre-wrap', however, the editing rules will instead simply put two regular spaces between the words, and should the two words be split at the end of a line, the spaces would be neatly removed from the rendering.
An
editing
host
is
either
an
HTML
element
with
its
contenteditable
attribute
in
the
true
state,
or
a
child
HTML
element
of
a
Document
whose
design
mode
enabled
is
true.
The
definition
of
the
terms
active
range
,
editing
host
of
,
and
editable
,
the
user
interface
requirements
of
elements
that
are
editing
hosts
or
editable
,
the
execCommand()
,
queryCommandEnabled()
,
queryCommandIndeterm()
,
queryCommandState()
,
queryCommandSupported()
,
and
queryCommandValue()
methods,
text
selections,
and
the
delete
the
selection
algorithm
are
defined
in
execCommand
.
[EXECCOMMAND]
Support in all current engines.
User
agents
can
support
the
checking
of
spelling
and
grammar
of
editable
text,
either
in
form
controls
(such
as
the
value
of
textarea
elements),
or
in
elements
in
an
editing
host
(e.g.
using
contenteditable
).
For each element, user agents must establish a default behavior , either through defaults or through preferences expressed by the user. There are three possible default behaviors for each element:
spellcheck
attribute.
spellcheck
attribute.
The
spellcheck
attribute
is
an
enumerated
attribute
whose
keywords
are
the
empty
string,
true
and
false
.
The
empty
string
and
the
true
keyword
map
to
the
true
state.
The
false
keyword
maps
to
the
false
state.
In
addition,
there
is
a
third
state,
the
default
state,
which
is
the
missing
value
default
and
the
invalid
value
default
.
The
true
state
indicates
that
the
element
is
to
have
its
spelling
and
grammar
checked.
The
default
state
indicates
that
the
element
is
to
act
according
to
a
default
behavior,
possibly
based
on
the
parent
element's
own
spellcheck
state,
as
defined
below.
The
false
state
indicates
that
the
element
is
not
to
be
checked.
spellcheck
[
=
value
]
Returns true if the element is to have its spelling and grammar checked; otherwise, returns false.
Can
be
set,
to
override
the
default
and
set
the
spellcheck
content
attribute.
The
spellcheck
IDL
attribute,
on
getting,
must
return
true
if
the
element's
spellcheck
content
attribute
is
in
the
true
state,
or
if
the
element's
spellcheck
content
attribute
is
in
the
default
state
and
the
element's
default
behavior
is
true-by-default
,
or
if
the
element's
spellcheck
content
attribute
is
in
the
default
state
and
the
element's
default
behavior
is
inherit-by-default
and
the
element's
parent
element's
spellcheck
IDL
attribute
would
return
true;
otherwise,
if
none
of
those
conditions
applies,
then
the
attribute
must
instead
return
false.
The
spellcheck
IDL
attribute
is
not
affected
by
user
preferences
that
override
the
spellcheck
content
attribute,
and
therefore
might
not
reflect
the
actual
spellchecking
state.
On
setting,
if
the
new
value
is
true,
then
the
element's
spellcheck
content
attribute
must
be
set
to
the
literal
string
"
true
",
otherwise
it
must
be
set
to
the
literal
string
"
false
".
User agents must only consider the following pieces of text as checkable for the purposes of this feature:
input
elements
whose
type
attributes
are
in
the
Text
,
Search
,
URL
,
or
Email
states
and
that
are
mutable
(i.e.
that
do
not
have
the
readonly
attribute
specified
and
that
are
not
disabled
).
textarea
elements
that
do
not
have
a
readonly
attribute
and
that
are
not
disabled
.
Text
nodes
that
are
children
of
editing
hosts
or
editable
elements.
For
text
that
is
part
of
a
Text
node,
the
element
with
which
the
text
is
associated
is
the
element
that
is
the
immediate
parent
of
the
first
character
of
the
word,
sentence,
or
other
piece
of
text.
For
text
in
attributes,
it
is
the
attribute's
element.
For
the
values
of
input
and
textarea
elements,
it
is
the
element
itself.
To determine if a word, sentence, or other piece of text in an applicable element (as defined above) is to have spelling- and grammar-checking enabled, the UA must use the following algorithm:
spellcheck
content
attribute,
then:
if
that
attribute
is
in
the
true
state,
then
checking
is
enabled;
otherwise,
if
that
attribute
is
in
the
false
state,
then
checking
is
disabled.
spellcheck
content
attribute
that
is
not
in
the
default
state,
then:
if
the
nearest
such
ancestor's
spellcheck
content
attribute
is
in
the
true
state,
then
checking
is
enabled;
otherwise,
checking
is
disabled.
If
the
checking
is
enabled
for
a
word/sentence/text,
the
user
agent
should
indicate
spelling
and
grammar
errors
in
that
text.
User
agents
should
take
into
account
the
other
semantics
given
in
the
document
when
suggesting
spelling
and
grammar
corrections.
User
agents
may
use
the
language
of
the
element
to
determine
what
spelling
and
grammar
rules
to
use,
or
may
use
the
user's
preferred
language
settings.
UAs
should
use
input
element
attributes
such
as
pattern
to
ensure
that
the
resulting
value
is
valid,
where
possible.
If checking is disabled, the user agent should not indicate spelling or grammar errors for that text.
The element with ID "a" in the following example would be the one used to determine if the word "Hello" is checked for spelling errors. In this example, it would not be.
<div contenteditable="true">
<span spellcheck="false" id="a">Hell</span><em>o!</em>
</div>
The
element
with
ID
"b"
in
the
following
example
would
have
checking
enabled
(the
leading
space
character
in
the
attribute's
value
on
the
input
element
causes
the
attribute
to
be
ignored,
so
the
ancestor's
value
is
used
instead,
regardless
of
the
default).
<p spellcheck="true">
<label>Name: <input spellcheck=" false" id="b"></label>
</p>
This specification does not define the user interface for spelling and grammar checkers. A user agent could offer on-demand checking, could perform continuous checking while the checking is enabled, or could use other interfaces.
Global_attributes/autocapitalize
Some
methods
of
entering
text,
for
example
virtual
keyboards
on
mobile
devices,
and
also
voice
input,
often
assist
users
by
automatically
capitalizing
the
first
letter
of
sentences
(when
composing
text
in
a
language
with
this
convention).
A
virtual
keyboard
that
implements
autocapitalization
might
automatically
switch
to
showing
uppercase
letters
(but
allow
the
user
to
toggle
it
back
to
lowercase)
when
a
letter
that
should
be
autocapitalized
is
about
to
be
typed.
Other
types
of
input,
for
example
voice
input,
may
perform
autocapitalization
in
a
way
that
does
not
give
users
an
option
to
intervene
first.
The
autocapitalize
attribute
allows
authors
to
control
such
behavior.
The
autocapitalize
attribute,
as
typically
implemented,
does
not
affect
behavior
when
typing
on
a
physical
keyboard.
(For
this
reason,
as
well
as
the
ability
for
users
to
override
the
autocapitalization
behavior
in
some
cases
or
edit
the
text
after
initial
input,
the
attribute
must
not
be
relied
on
for
any
sort
of
input
validation.)
The
autocapitalize
attribute
can
be
used
on
an
editing
host
to
control
autocapitalization
behavior
for
the
hosted
editable
region,
on
an
input
or
textarea
element
to
control
the
behavior
for
inputting
text
into
that
element,
or
on
a
form
element
to
control
the
default
behavior
for
all
autocapitalize-inheriting
elements
associated
with
the
form
element.
The
autocapitalize
attribute
never
causes
autocapitalization
to
be
enabled
for
input
elements
whose
type
attribute
is
in
one
of
the
URL
,
Email
,
or
Password
states.
(This
behavior
is
included
in
the
used
autocapitalization
hint
algorithm
below.)
The autocapitalization processing model is based on selecting among five autocapitalization hints , defined as follows:
The user agent and input method should use make their own determination of whether or not to enable autocapitalization.
No autocapitalization should be applied (all letters should default to lowercase).
The first letter of each sentence should default to a capital letter; all other letters should default to lowercase.
The first letter of each word should default to a capital letter; all other letters should default to lowercase.
All letters should default to uppercase.
The
autocapitalize
attribute
is
an
enumerated
attribute
whose
states
are
the
possible
autocapitalization
hints
.
The
autocapitalization
hint
specified
by
the
attribute's
state
combines
with
other
considerations
to
form
the
used
autocapitalization
hint
,
which
informs
the
behavior
of
the
user
agent.
The
keywords
for
this
attribute
and
their
state
mappings
are
as
follows:
Keyword | State |
---|---|
off
| none |
none
| |
on
| sentences |
sentences
| |
words
| words |
characters
| characters |
The invalid value default is the sentences state. The missing value default is the default state.
autocapitalize
[
=
value
]
Returns
the
current
autocapitalization
state
for
the
element,
or
an
empty
string
if
it
hasn't
been
set.
Note
that
for
input
and
textarea
elements
that
inherit
their
state
from
a
form
element,
this
will
return
the
autocapitalization
state
of
the
form
element,
but
for
an
element
in
an
editable
region,
this
will
not
return
the
autocapitalization
state
of
the
editing
host
(unless
this
element
is,
in
fact,
the
editing
host
).
Can
be
set,
to
set
the
autocapitalize
content
attribute
(and
thereby
change
the
autocapitalization
behavior
for
the
element).
To compute the own autocapitalization hint of an element element , run the following steps:
If
the
autocapitalize
content
attribute
is
present
on
element
,
and
its
value
is
not
the
empty
string,
return
the
state
of
the
attribute.
If element is an autocapitalize-inheriting element and has a non-null form owner , return the own autocapitalization hint of element 's form owner .
Return default .
The
autocapitalize
IDL
attribute,
on
getting,
must
return
the
string
value
corresponding
to
own
autocapitalization
hint
of
the
element,
with
the
exception
that
the
default
state
maps
to
the
empty
string.
On
setting,
it
must
set
the
autocapitalize
content
attribute
to
the
given
new
value.
User agents that support customizable autocapitalization behavior for a text input method and wish to allow web developers to control this functionality should, during text input into an element, compute the used autocapitalization hint for the element. This will be an autocapitalization hint that describes the recommended autocapitalization behavior for text input into the element.
User agents or input methods may choose to ignore or override the used autocapitalization hint in certain circumstances.
The used autocapitalization hint for an element element is computed using the following algorithm:
If
element
is
an
input
element
whose
type
attribute
is
in
one
of
the
URL
,
Email
,
or
Password
states,
then
return
default
.
If
element
is
an
input
element
or
a
textarea
element,
then
return
element
's
own
autocapitalization
hint
.
If element is an editing host or an editable element, then return the own autocapitalization hint of the editing host of element .
Assert: this step is never reached, since text input only occurs in elements that meet one of the above criteria.
inputmode
attribute
Support in all current engines.
User
agents
can
support
the
inputmode
attribute
on
form
controls
(such
as
the
value
of
textarea
elements),
or
in
elements
in
an
editing
host
(e.g.,
using
contenteditable
).
The
inputmode
content
attribute
is
an
enumerated
attribute
that
specifies
what
kind
of
input
mechanism
would
be
most
helpful
for
users
entering
content.
Keyword | Description |
---|---|
none
| The user agent should not display a virtual keyboard. This keyword is useful for content that renders its own keyboard control. |
text
| The user agent should display a virtual keyboard capable of text input in the user's locale. |
tel
| The user agent should display a virtual keyboard capable of telephone number input. This should including keys for the digits 0 to 9, the "#" character, and the "*" character. In some locales, this can also include alphabetic mnemonic labels (e.g., in the US, the key labeled "2" is historically also labeled with the letters A, B, and C). |
url
| The user agent should display a virtual keyboard capable of text input in the user's locale, with keys for aiding in the input of URLs , such as that for the "/" and "." characters and for quick input of strings commonly found in domain names such as "www." or ".com". |
email
| The user agent should display a virtual keyboard capable of text input in the user's locale, with keys for aiding in the input of email addresses, such as that for the "@" character and the "." character. |
numeric
| The user agent should display a virtual keyboard capable of numeric input. This keyword is useful for PIN entry. |
decimal
| The user agent should display a virtual keyboard capable of fractional numeric input. Numeric keys and the format separator for the locale should be shown. |
search
| The user agent should display a virtual keyboard optimized for search. |
The
inputMode
IDL
attribute
must
reflect
the
inputmode
content
attribute,
limited
to
only
known
values
.
When
inputmode
is
unspecified
(or
is
in
a
state
not
supported
by
the
user
agent),
the
user
agent
should
determine
the
default
virtual
keyboard
to
be
shown.
Contextual
information
such
as
the
input
type
or
pattern
attributes
should
be
used
to
determine
which
type
of
virtual
keyboard
should
be
presented
to
the
user.
enterkeyhint
attribute
User
agents
can
support
the
enterkeyhint
attribute
on
form
controls
(such
as
the
value
of
textarea
elements),
or
in
elements
in
an
editing
host
(e.g.,
using
contenteditable
).
The
enterkeyhint
content
attribute
is
an
enumerated
attribute
that
specifies
what
action
label
(or
icon)
to
present
for
the
enter
key
on
virtual
keyboards.
This
allows
authors
to
customize
the
presentation
of
the
enter
key
in
order
to
make
it
more
helpful
for
users.
Keyword | Description |
---|---|
enter
| The user agent should present a cue for the operation 'enter', typically inserting a new line. |
done
| The user agent should present a cue for the operation 'done', typically meaning there is nothing more to input and the input method editor (IME) will be closed. |
go
| The user agent should present a cue for the operation 'go', typically meaning to take the user to the target of the text they typed. |
next
| The user agent should present a cue for the operation 'next', typically taking the user to the next field that will accept text. |
previous
| The user agent should present a cue for the operation 'previous', typically taking the user to the previous field that will accept text. |
search
| The user agent should present a cue for the operation 'search', typically taking the user to the results of searching for the text they have typed. |
send
| The user agent should present a cue for the operation 'send', typically delivering the text to its target. |
The
enterKeyHint
IDL
attribute
must
reflect
the
enterkeyhint
content
attribute,
limited
to
only
known
values
.
When
enterkeyhint
is
unspecified
(or
is
in
a
state
not
supported
by
the
user
agent),
the
user
agent
should
determine
the
default
action
label
(or
icon)
to
present.
Contextual
information
such
as
the
inputmode
,
type
,
or
pattern
attributes
should
be
used
to
determine
which
action
label
(or
icon)
to
present
on
the
virtual
keyboard.
This section defines find-in-page — a common user-agent mechanism which allows users to search through the contents of the page for particular information.
Access to find-in-page feature is provided via a find-in-page interface . This is a user-agent provided user interface, which allows the user to specify input and the parameters of the search. This interface can appear as a result of a shortcut or a menu selection.
A combination of text input and settings in the find-in-page interface represents the user query . This typically includes the text that the user wants to search for, as well as optional settings (e.g., the ability to restrict the search to whole words only).
The user-agent processes page contents for a given query , and identifies zero or more matches , which are content ranges that satisfy the user query .
One of the matches is identified to the user as the active match . It is highlighted and scrolled into view. The user can navigate through the matches by advancing the active match using the find-in-page interface .
Issue
#3539
tracks
standardizing
how
find-in-page
underlies
the
currently-unspecified
window.find()
API.
The find-in-page process is invoked in the context of a document, and may have an effect on the selection of that document. Specifically, the range that defines the active match can dictate the current selection. These selection updates, however, can happen at different times during the find-in-page process (e.g. upon the find-in-page interface dismissal or upon a change in the active match range).