static
Class Event
The event utility provides functions to add and remove event listeners,
event cleansing. It also tries to automatically remove listeners it
registers during the unload event.
Properties
DOMReady
- static boolean
True when the document is initially usable
addListener/removeListener can throw errors in unexpected scenarios.
These errors are suppressed, the method returns false, and this property
is set
The poll interval in milliseconds
The number of times we should look for elements that are not
in the DOM at the time the event is requested after the document
has been loaded. The default is 2000@amp;20 ms, so it will poll
for 40 seconds or until all outstanding handlers are bound
(whichever comes first).
Methods
static
Boolean
attach
(
type
,
fn
,
el
,
obj
,
args
)
Appends an event handler
- Parameters:
-
type
<String>
The type of event to append
-
fn
<Function>
The method the event invokes
-
el
<String|HTMLElement|Array|NodeList>
An id, an element
reference, or a collection of ids and/or elements to assign the
listener to.
-
obj
<Object>
An arbitrary object that will be
passed as a parameter to the handler
-
args
<Boolean|object>
0..n arguments to pass to the callback
- Returns:
Boolean
- True if the action was successful or defered,
false if one or more of the elements
could not have the listener attached,
or if the operation throws an exception.
static
boolean
detach
(
el
,
type
,
fn
)
Removes an event listener. Supports the signature the event was bound
with, but the preferred way to remove listeners is using the handle
that is returned when using Y.on
- Parameters:
-
el
<String|HTMLElement|Array|NodeList>
An id, an element
reference, or a collection of ids and/or elements to remove
the listener from.
-
type
<String>
the type of event to remove.
-
fn
<Function>
the method the event invokes. If fn is
undefined, then all event handlers for the type of event are * removed.
- Returns:
boolean
- true if the unbind was successful, false * otherwise.
static
string
generateId
(
el
)
Generates an unique ID for the element if it does not already
have one.
- Parameters:
-
el
<object>
the element to create the id for
- Returns:
string
- the resulting id of the element
static
Event
getEvent
(
e
,
el
)
Finds the event in the window object, the caller's arguments, or
in the arguments of another method in the callstack. This is
executed automatically for events registered through the event
manager, so the implementer should not normally need to execute
this function at all.
- Parameters:
-
e
<Event>
the event parameter from the handler
-
el
<HTMLElement>
the element the listener was attached to
- Returns:
Event
- the event
static
Y.Custom.Event
getListeners
(
el
,
type
)
Returns all listeners attached to the given element via addListener.
Optionally, you can specify a specific type of event to return.
- Parameters:
-
el
<HTMLElement|string>
the element or element id to inspect
-
type
<string>
optional type of listener to return. If
left out, all listeners will be returned
- Returns:
Y.Custom.Event
- the custom event wrapper for the DOM event(s)
static
void
onAvailable
(
id
,
fn
,
p_obj
,
p_override
,
checkContent
)
Executes the supplied callback when the item with the supplied
id is found. This is meant to be used to execute behavior as
soon as possible as the page loads. If you use this after the
initial page load it will poll for a fixed time for the element.
The number of times it will poll and the frequency are
configurable. By default it will poll for 10 seconds.
The callback is executed with a single parameter:
the custom object parameter, if provided.
- Parameters:
-
id
<string||string[]>
the id of the element, or an array
of ids to look for.
-
fn
<function>
what to execute when the element is found.
-
p_obj
<object>
an optional object to be passed back as
a parameter to fn.
-
p_override
<boolean|object>
If set to true, fn will execute
in the context of p_obj, if set to an object it
will execute in the context of that object
-
checkContent
<boolean>
check child node readiness (onContentReady)
- Returns:
void
Deprecated Use Y.on("available")
static
void
onContentReady
(
id
,
fn
,
p_obj
,
p_override
)
Works the same way as onAvailable, but additionally checks the
state of sibling elements to determine if the content of the
available element is safe to modify.
The callback is executed with a single parameter:
the custom object parameter, if provided.
- Parameters:
-
id
<string>
the id of the element to look for.
-
fn
<function>
what to execute when the element is ready.
-
p_obj
<object>
an optional object to be passed back as
a parameter to fn.
-
p_override
<boolean|object>
If set to true, fn will execute
in the context of p_obj. If an object, fn will
exectute in the context of that object
- Returns:
void
Deprecated Use Y.on("contentready")
static
void
purgeElement
(
el
,
recurse
,
type
)
Removes all listeners attached to the given element via addListener.
Optionally, the node's children can also be purged.
Optionally, you can specify a specific type of event to remove.
- Parameters:
-
el
<HTMLElement>
the element to purge
-
recurse
<boolean>
recursively purge this element's children
as well. Use with caution.
-
type
<string>
optional type of listener to purge. If
left out, all listeners will be removed
- Returns:
void