event-custom-base-debug.js revision 4fd744238f7e70d38269d5f0c36ece8a8c2295be
YUI.add('event-custom-base', function(Y) {
/**
* Custom event engine, DOM event listener abstraction layer, synthetic DOM
* events.
* @module event-custom
*/
Y.Env.evt = {
handles: {},
plugins: {}
};
/**
* Custom event engine, DOM event listener abstraction layer, synthetic DOM
* events.
* @module event-custom
* @submodule event-custom-base
*/
/**
* Allows for the insertion of methods that are executed before or after
* a specified method
* @class Do
* @static
*/
var DO_BEFORE = 0,
DO_AFTER = 1,
DO = {
/**
* Cache of objects touched by the utility
* @property objs
* @static
*/
objs: {},
/**
* <p>Execute the supplied method before the specified function. Wrapping
* function may optionally return an instance of the following classes to
* further alter runtime behavior:</p>
* <dl>
* <dt></code>Y.Do.Halt(message, returnValue)</code></dt>
* <dd>Immediatly stop execution and return
* <code>returnValue</code>. No other wrapping functions will be
* executed.</dd>
* <dt></code>Y.Do.AlterArgs(message, newArgArray)</code></dt>
* <dd>Replace the arguments that the original function will be
* called with.</dd>
* <dt></code>Y.Do.Prevent(message)</code></dt>
* <dd>Don't execute the wrapped function. Other before phase
* wrappers will be executed.</dd>
* </dl>
*
* @method before
* @param fn {Function} the function to execute
* @param obj the object hosting the method to displace
* @param sFn {string} the name of the method to displace
* @param c The execution context for fn
* @param arg* {mixed} 0..n additional arguments to supply to the subscriber
* when the event fires.
* @return {string} handle for the subscription
* @static
*/
before: function(fn, obj, sFn, c) {
// Y.log('Do before: ' + sFn, 'info', 'event');
var f = fn, a;
if (c) {
a = [fn, c].concat(Y.Array(arguments, 4, true));
f = Y.rbind.apply(Y, a);
}
return this._inject(DO_BEFORE, f, obj, sFn);
},
/**
* <p>Execute the supplied method after the specified function. Wrapping
* function may optionally return an instance of the following classes to
* further alter runtime behavior:</p>
* <dl>
* <dt></code>Y.Do.Halt(message, returnValue)</code></dt>
* <dd>Immediatly stop execution and return
* <code>returnValue</code>. No other wrapping functions will be
* executed.</dd>
* <dt></code>Y.Do.AlterReturn(message, returnValue)</code></dt>
* <dd>Return <code>returnValue</code> instead of the wrapped
* method's original return value. This can be further altered by
* other after phase wrappers.</dd>
* </dl>
*
* <p>The static properties <code>Y.Do.originalRetVal</code> and
* <code>Y.Do.currentRetVal</code> will be populated for reference.</p>
*
* @method after
* @param fn {Function} the function to execute
* @param obj the object hosting the method to displace
* @param sFn {string} the name of the method to displace
* @param c The execution context for fn
* @param arg* {mixed} 0..n additional arguments to supply to the subscriber
* @return {string} handle for the subscription
* @static
*/
after: function(fn, obj, sFn, c) {
var f = fn, a;
if (c) {
a = [fn, c].concat(Y.Array(arguments, 4, true));
f = Y.rbind.apply(Y, a);
}
return this._inject(DO_AFTER, f, obj, sFn);
},
/**
* Execute the supplied method before or after the specified function.
* Used by <code>before</code> and <code>after</code>.
*
* @method _inject
* @param when {string} before or after
* @param fn {Function} the function to execute
* @param obj the object hosting the method to displace
* @param sFn {string} the name of the method to displace
* @param c The execution context for fn
* @return {string} handle for the subscription
* @private
* @static
*/
_inject: function(when, fn, obj, sFn) {
// object id
var id = Y.stamp(obj), o, sid;
if (! this.objs[id]) {
// create a map entry for the obj if it doesn't exist
this.objs[id] = {};
}
o = this.objs[id];
if (! o[sFn]) {
// create a map entry for the method if it doesn't exist
o[sFn] = new Y.Do.Method(obj, sFn);
// re-route the method to our wrapper
obj[sFn] =
function() {
return o[sFn].exec.apply(o[sFn], arguments);
};
}
// subscriber id
sid = id + Y.stamp(fn) + sFn;
// register the callback
o[sFn].register(sid, fn, when);
return new Y.EventHandle(o[sFn], sid);
},
/**
* Detach a before or after subscription.
*
* @method detach
* @param handle {string} the subscription handle
* @static
*/
detach: function(handle) {
if (handle.detach) {
handle.detach();
}
},
_unload: function(e, me) {
}
};
Y.Do = DO;
//////////////////////////////////////////////////////////////////////////
/**
* Contains the return value from the wrapped method, accessible
* by 'after' event listeners.
*
* @property originalRetVal
* @static
* @since 3.2.0
*/
/**
* Contains the current state of the return value, consumable by
* 'after' event listeners, and updated if an after subscriber
* changes the return value generated by the wrapped function.
*
* @property currentRetVal
* @static
* @since 3.2.0
*/
//////////////////////////////////////////////////////////////////////////
/**
* Wrapper for a displaced method with aop enabled
* @class Do.Method
* @constructor
* @param obj The object to operate on
* @param sFn The name of the method to displace
*/
DO.Method = function(obj, sFn) {
this.obj = obj;
this.methodName = sFn;
this.method = obj[sFn];
this.before = {};
this.after = {};
};
/**
* Register a aop subscriber
* @method register
* @param sid {string} the subscriber id
* @param fn {Function} the function to execute
* @param when {string} when to execute the function
*/
DO.Method.prototype.register = function (sid, fn, when) {
if (when) {
this.after[sid] = fn;
} else {
this.before[sid] = fn;
}
};
/**
* Unregister a aop subscriber
* @method delete
* @param sid {string} the subscriber id
* @param fn {Function} the function to execute
* @param when {string} when to execute the function
*/
DO.Method.prototype._delete = function (sid) {
// Y.log('Y.Do._delete: ' + sid, 'info', 'Event');
delete this.before[sid];
delete this.after[sid];
};
/**
* <p>Execute the wrapped method. All arguments are passed into the wrapping
* functions. If any of the before wrappers return an instance of
* <code>Y.Do.Halt</code> or <code>Y.Do.Prevent</code>, neither the wrapped
* function nor any after phase subscribers will be executed.</p>
*
* <p>The return value will be the return value of the wrapped function or one
* provided by a wrapper function via an instance of <code>Y.Do.Halt</code> or
* <code>Y.Do.AlterReturn</code>.
*
* @method exec
* @param arg* {any} Arguments are passed to the wrapping and wrapped functions
* @return {any} Return value of wrapped function unless overwritten (see above)
*/
DO.Method.prototype.exec = function () {
var args = Y.Array(arguments, 0, true),
i, ret, newRet,
bf = this.before,
af = this.after,
prevented = false;
// execute before
for (i in bf) {
if (bf.hasOwnProperty(i)) {
ret = bf[i].apply(this.obj, args);
if (ret) {
switch (ret.constructor) {
case DO.Halt:
return ret.retVal;
case DO.AlterArgs:
args = ret.newArgs;
break;
case DO.Prevent:
prevented = true;
break;
default:
}
}
}
}
// execute method
if (!prevented) {
ret = this.method.apply(this.obj, args);
}
DO.originalRetVal = ret;
DO.currentRetVal = ret;
// execute after methods.
for (i in af) {
if (af.hasOwnProperty(i)) {
newRet = af[i].apply(this.obj, args);
// Stop processing if a Halt object is returned
if (newRet && newRet.constructor == DO.Halt) {
return newRet.retVal;
// Check for a new return value
} else if (newRet && newRet.constructor == DO.AlterReturn) {
ret = newRet.newRetVal;
// Update the static retval state
DO.currentRetVal = ret;
}
}
}
return ret;
};
//////////////////////////////////////////////////////////////////////////
/**
* Return an AlterArgs object when you want to change the arguments that
* were passed into the function. Useful for Do.before subscribers. An
* example would be a service that scrubs out illegal characters prior to
* executing the core business logic.
* @class Do.AlterArgs
* @constructor
* @param msg {String} (optional) Explanation of the altered return value
* @param newArgs {Array} Call parameters to be used for the original method
* instead of the arguments originally passed in.
*/
DO.AlterArgs = function(msg, newArgs) {
this.msg = msg;
this.newArgs = newArgs;
};
/**
* Return an AlterReturn object when you want to change the result returned
* from the core method to the caller. Useful for Do.after subscribers.
* @class Do.AlterReturn
* @constructor
* @param msg {String} (optional) Explanation of the altered return value
* @param newRetVal {any} Return value passed to code that invoked the wrapped
* function.
*/
DO.AlterReturn = function(msg, newRetVal) {
this.msg = msg;
this.newRetVal = newRetVal;
};
/**
* Return a Halt object when you want to terminate the execution
* of all subsequent subscribers as well as the wrapped method
* if it has not exectued yet. Useful for Do.before subscribers.
* @class Do.Halt
* @constructor
* @param msg {String} (optional) Explanation of why the termination was done
* @param retVal {any} Return value passed to code that invoked the wrapped
* function.
*/
DO.Halt = function(msg, retVal) {
this.msg = msg;
this.retVal = retVal;
};
/**
* Return a Prevent object when you want to prevent the wrapped function
* from executing, but want the remaining listeners to execute. Useful
* for Do.before subscribers.
* @class Do.Prevent
* @constructor
* @param msg {String} (optional) Explanation of why the termination was done
*/
DO.Prevent = function(msg) {
this.msg = msg;
};
/**
* Return an Error object when you want to terminate the execution
* of all subsequent method calls.
* @class Do.Error
* @constructor
* @param msg {String} (optional) Explanation of the altered return value
* @param retVal {any} Return value passed to code that invoked the wrapped
* function.
* @deprecated use Y.Do.Halt or Y.Do.Prevent
*/
DO.Error = DO.Halt;
//////////////////////////////////////////////////////////////////////////
// Y["Event"] && Y.Event.addListener(window, "unload", Y.Do._unload, Y.Do);
/**
* Custom event engine, DOM event listener abstraction layer, synthetic DOM
* events.
* @module event-custom
* @submodule event-custom-base
*/
// var onsubscribeType = "_event:onsub",
var AFTER = 'after',
CONFIGS = [
'broadcast',
'monitored',
'bubbles',
'context',
'contextFn',
'currentTarget',
'defaultFn',
'defaultTargetOnly',
'details',
'emitFacade',
'fireOnce',
'async',
'host',
'preventable',
'preventedFn',
'queuable',
'silent',
'stoppedFn',
'target',
'type'
],
YUI3_SIGNATURE = 9,
YUI_LOG = 'yui:log';
/**
* The CustomEvent class lets you define events for your application
* that can be subscribed to by one or more independent component.
*
* @param {String} type The type of event, which is passed to the callback
* when the event fires.
* @param {object} o configuration object.
* @class CustomEvent
* @constructor
*/
Y.CustomEvent = function(type, o) {
// if (arguments.length > 2) {
// this.log('CustomEvent context and silent are now in the config', 'warn', 'Event');
// }
o = o || {};
this.id = Y.stamp(this);
/**
* The type of event, returned to subscribers when the event fires
* @property type
* @type string
*/
this.type = type;
/**
* The context the the event will fire from by default. Defaults to the YUI
* instance.
* @property context
* @type object
*/
this.context = Y;
/**
* Monitor when an event is attached or detached.
*
* @property monitored
* @type boolean
*/
// this.monitored = false;
this.logSystem = (type == YUI_LOG);
/**
* If 0, this event does not broadcast. If 1, the YUI instance is notified
* every time this event fires. If 2, the YUI instance and the YUI global
* (if event is enabled on the global) are notified every time this event
* fires.
* @property broadcast
* @type int
*/
// this.broadcast = 0;
/**
* By default all custom events are logged in the debug build, set silent
* to true to disable debug outpu for this event.
* @property silent
* @type boolean
*/
this.silent = this.logSystem;
/**
* Specifies whether this event should be queued when the host is actively
* processing an event. This will effect exectution order of the callbacks
* for the various events.
* @property queuable
* @type boolean
* @default false
*/
// this.queuable = false;
/**
* The subscribers to this event
* @property subscribers
* @type Subscriber {}
*/
this.subscribers = {};
/**
* 'After' subscribers
* @property afters
* @type Subscriber {}
*/
this.afters = {};
/**
* This event has fired if true
*
* @property fired
* @type boolean
* @default false;
*/
// this.fired = false;
/**
* An array containing the arguments the custom event
* was last fired with.
* @property firedWith
* @type Array
*/
// this.firedWith;
/**
* This event should only fire one time if true, and if
* it has fired, any new subscribers should be notified
* immediately.
*
* @property fireOnce
* @type boolean
* @default false;
*/
// this.fireOnce = false;
/**
* fireOnce listeners will fire syncronously unless async
* is set to true
* @property async
* @type boolean
* @default false
*/
//this.async = false;
/**
* Flag for stopPropagation that is modified during fire()
* 1 means to stop propagation to bubble targets. 2 means
* to also stop additional subscribers on this target.
* @property stopped
* @type int
*/
// this.stopped = 0;
/**
* Flag for preventDefault that is modified during fire().
* if it is not 0, the default behavior for this event
* @property prevented
* @type int
*/
// this.prevented = 0;
/**
* Specifies the host for this custom event. This is used
* to enable event bubbling
* @property host
* @type EventTarget
*/
// this.host = null;
/**
* The default function to execute after event listeners
* have fire, but only if the default action was not
* prevented.
* @property defaultFn
* @type Function
*/
// this.defaultFn = null;
/**
* The function to execute if a subscriber calls
* stopPropagation or stopImmediatePropagation
* @property stoppedFn
* @type Function
*/
// this.stoppedFn = null;
/**
* The function to execute if a subscriber calls
* preventDefault
* @property preventedFn
* @type Function
*/
// this.preventedFn = null;
/**
* Specifies whether or not this event's default function
* can be cancelled by a subscriber by executing preventDefault()
* on the event facade
* @property preventable
* @type boolean
* @default true
*/
this.preventable = true;
/**
* Specifies whether or not a subscriber can stop the event propagation
* via stopPropagation(), stopImmediatePropagation(), or halt()
*
* Events can only bubble if emitFacade is true.
*
* @property bubbles
* @type boolean
* @default true
*/
this.bubbles = true;
/**
* Supports multiple options for listener signatures in order to
* port YUI 2 apps.
* @property signature
* @type int
* @default 9
*/
this.signature = YUI3_SIGNATURE;
this.subCount = 0;
this.afterCount = 0;
// this.hasSubscribers = false;
// this.hasAfters = false;
/**
* If set to true, the custom event will deliver an EventFacade object
* that is similar to a DOM event object.
* @property emitFacade
* @type boolean
* @default false
*/
// this.emitFacade = false;
this.applyConfig(o, true);
// this.log("Creating " + this.type);
};
Y.CustomEvent.prototype = {
constructor: Y.CustomEvent,
/**
* Returns the number of subscribers for this event as the sum of the on()
* subscribers and after() subscribers.
*
* @method hasSubs
* @return Number
*/
hasSubs: function(when) {
var s = this.subCount, a = this.afterCount, sib = this.sibling;
if (sib) {
s += sib.subCount;
a += sib.afterCount;
}
if (when) {
return (when == 'after') ? a : s;
}
return (s + a);
},
/**
* Monitor the event state for the subscribed event. The first parameter
* is what should be monitored, the rest are the normal parameters when
* subscribing to an event.
* @method monitor
* @param what {string} what to monitor ('detach', 'attach', 'publish').
* @return {EventHandle} return value from the monitor event subscription.
*/
monitor: function(what) {
this.monitored = true;
var type = this.id + '|' + this.type + '_' + what,
args = Y.Array(arguments, 0, true);
args[0] = type;
return this.host.on.apply(this.host, args);
},
/**
* Get all of the subscribers to this event and any sibling event
* @method getSubs
* @return {Array} first item is the on subscribers, second the after.
*/
getSubs: function() {
var s = Y.merge(this.subscribers), a = Y.merge(this.afters), sib = this.sibling;
if (sib) {
Y.mix(s, sib.subscribers);
Y.mix(a, sib.afters);
}
return [s, a];
},
/**
* Apply configuration properties. Only applies the CONFIG whitelist
* @method applyConfig
* @param o hash of properties to apply.
* @param force {boolean} if true, properties that exist on the event
* will be overwritten.
*/
applyConfig: function(o, force) {
if (o) {
Y.mix(this, o, force, CONFIGS);
}
},
/**
* Create the Subscription for subscribing function, context, and bound
* arguments. If this is a fireOnce event, the subscriber is immediately
* notified.
*
* @method _on
* @param fn {Function} Subscription callback
* @param [context] {Object} Override `this` in the callback
* @param [args] {Array} bound arguments that will be passed to the callback after the arguments generated by fire()
* @param [when] {String} "after" to slot into after subscribers
* @return {EventHandle}
* @protected
*/
_on: function(fn, context, args, when) {
if (!fn) {
this.log('Invalid callback for CE: ' + this.type);
}
var s = new Y.Subscriber(fn, context, args, when);
if (this.fireOnce && this.fired) {
if (this.async) {
setTimeout(Y.bind(this._notify, this, s, this.firedWith), 0);
} else {
this._notify(s, this.firedWith);
}
}
if (when == AFTER) {
this.afters[s.id] = s;
this.afterCount++;
} else {
this.subscribers[s.id] = s;
this.subCount++;
}
return new Y.EventHandle(this, s);
},
/**
* Listen for this event
* @method subscribe
* @param {Function} fn The function to execute.
* @return {EventHandle} Unsubscribe handle.
* @deprecated use on.
*/
subscribe: function(fn, context) {
Y.log('ce.subscribe deprecated, use "on"', 'warn', 'deprecated');
var a = (arguments.length > 2) ? Y.Array(arguments, 2, true) : null;
return this._on(fn, context, a, true);
},
/**
* Listen for this event
* @method on
* @param {Function} fn The function to execute.
* @param {object} context optional execution context.
* @param {mixed} arg* 0..n additional arguments to supply to the subscriber
* when the event fires.
* @return {EventHandle} An object with a detach method to detch the handler(s).
*/
on: function(fn, context) {
var a = (arguments.length > 2) ? Y.Array(arguments, 2, true) : null;
if (this.host) {
this.host._monitor('attach', this.type, {
args: arguments
});
}
return this._on(fn, context, a, true);
},
/**
* Listen for this event after the normal subscribers have been notified and
* the default behavior has been applied. If a normal subscriber prevents the
* default behavior, it also prevents after listeners from firing.
* @method after
* @param {Function} fn The function to execute.
* @param {object} context optional execution context.
* @param {mixed} arg* 0..n additional arguments to supply to the subscriber
* when the event fires.
* @return {EventHandle} handle Unsubscribe handle.
*/
after: function(fn, context) {
var a = (arguments.length > 2) ? Y.Array(arguments, 2, true) : null;
return this._on(fn, context, a, AFTER);
},
/**
* Detach listeners.
* @method detach
* @param {Function} fn The subscribed function to remove, if not supplied
* all will be removed.
* @param {Object} context The context object passed to subscribe.
* @return {int} returns the number of subscribers unsubscribed.
*/
detach: function(fn, context) {
// unsubscribe handle
if (fn && fn.detach) {
return fn.detach();
}
var i, s,
found = 0,
subs = Y.merge(this.subscribers, this.afters);
for (i in subs) {
if (subs.hasOwnProperty(i)) {
s = subs[i];
if (s && (!fn || fn === s.fn)) {
this._delete(s);
found++;
}
}
}
return found;
},
/**
* Detach listeners.
* @method unsubscribe
* @param {Function} fn The subscribed function to remove, if not supplied
* all will be removed.
* @param {Object} context The context object passed to subscribe.
* @return {int|undefined} returns the number of subscribers unsubscribed.
* @deprecated use detach.
*/
unsubscribe: function() {
return this.detach.apply(this, arguments);
},
/**
* Notify a single subscriber
* @method _notify
* @param {Subscriber} s the subscriber.
* @param {Array} args the arguments array to apply to the listener.
* @protected
*/
_notify: function(s, args, ef) {
this.log(this.type + '->' + 'sub: ' + s.id);
var ret;
ret = s.notify(args, this);
if (false === ret || this.stopped > 1) {
this.log(this.type + ' cancelled by subscriber');
return false;
}
return true;
},
/**
* Logger abstraction to centralize the application of the silent flag
* @method log
* @param {string} msg message to log.
* @param {string} cat log category.
*/
log: function(msg, cat) {
if (!this.silent) {
Y.log(this.id + ': ' + msg, cat || 'info', 'event');
}
},
/**
* Notifies the subscribers. The callback functions will be executed
* from the context specified when the event was created, and with the
* following parameters:
* <ul>
* <li>The type of event</li>
* <li>All of the arguments fire() was executed with as an array</li>
* <li>The custom object (if any) that was passed into the subscribe()
* method</li>
* </ul>
* @method fire
* @param {Object*} arguments an arbitrary set of parameters to pass to
* the handler.
* @return {boolean} false if one of the subscribers returned false,
* true otherwise.
*
*/
fire: function() {
if (this.fireOnce && this.fired) {
this.log('fireOnce event: ' + this.type + ' already fired');
return true;
} else {
var args = Y.Array(arguments, 0, true);
// this doesn't happen if the event isn't published
// this.host._monitor('fire', this.type, args);
this.fired = true;
this.firedWith = args;
if (this.emitFacade) {
return this.fireComplex(args);
} else {
return this.fireSimple(args);
}
}
},
/**
* Set up for notifying subscribers of non-emitFacade events.
*
* @method fireSimple
* @param args {Array} Arguments passed to fire()
* @return Boolean false if a subscriber returned false
* @protected
*/
fireSimple: function(args) {
this.stopped = 0;
this.prevented = 0;
if (this.hasSubs()) {
// this._procSubs(Y.merge(this.subscribers, this.afters), args);
var subs = this.getSubs();
this._procSubs(subs[0], args);
this._procSubs(subs[1], args);
}
this._broadcast(args);
return this.stopped ? false : true;
},
// Requires the event-custom-complex module for full funcitonality.
fireComplex: function(args) {
Y.log('Missing event-custom-complex needed to emit a facade for: ' + this.type);
args[0] = args[0] || {};
return this.fireSimple(args);
},
/**
* Notifies a list of subscribers.
*
* @method _procSubs
* @param subs {Array} List of subscribers
* @param args {Array} Arguments passed to fire()
* @param ef {}
* @return Boolean false if a subscriber returns false or stops the event
* propagation via e.stopPropagation(),
* e.stopImmediatePropagation(), or e.halt()
* @private
*/
_procSubs: function(subs, args, ef) {
var s, i;
for (i in subs) {
if (subs.hasOwnProperty(i)) {
s = subs[i];
if (s && s.fn) {
if (false === this._notify(s, args, ef)) {
this.stopped = 2;
}
if (this.stopped == 2) {
return false;
}
}
}
}
return true;
},
/**
* Notifies the YUI instance if the event is configured with broadcast = 1,
* and both the YUI instance and Y.Global if configured with broadcast = 2.
*
* @method _broadcast
* @param args {Array} Arguments sent to fire()
* @private
*/
_broadcast: function(args) {
if (!this.stopped && this.broadcast) {
var a = Y.Array(args);
a.unshift(this.type);
if (this.host !== Y) {
Y.fire.apply(Y, a);
}
if (this.broadcast == 2) {
Y.Global.fire.apply(Y.Global, a);
}
}
},
/**
* Removes all listeners
* @method unsubscribeAll
* @return {int} The number of listeners unsubscribed.
* @deprecated use detachAll.
*/
unsubscribeAll: function() {
return this.detachAll.apply(this, arguments);
},
/**
* Removes all listeners
* @method detachAll
* @return {int} The number of listeners unsubscribed.
*/
detachAll: function() {
return this.detach();
},
/**
* Deletes the subscriber from the internal store of on() and after()
* subscribers.
*
* @method _delete
* @param subscriber object.
* @private
*/
_delete: function(s) {
if (s) {
if (this.subscribers[s.id]) {
delete this.subscribers[s.id];
this.subCount--;
}
if (this.afters[s.id]) {
delete this.afters[s.id];
this.afterCount--;
}
}
if (this.host) {
this.host._monitor('detach', this.type, {
ce: this,
sub: s
});
}
if (s) {
// delete s.fn;
// delete s.context;
s.deleted = true;
}
}
};
/**
* Stores the subscriber information to be used when the event fires.
* @param {Function} fn The wrapped function to execute.
* @param {Object} context The value of the keyword 'this' in the listener.
* @param {Array} args* 0..n additional arguments to supply the listener.
*
* @class Subscriber
* @constructor
*/
Y.Subscriber = function(fn, context, args) {
/**
* The callback that will be execute when the event fires
* This is wrapped by Y.rbind if obj was supplied.
* @property fn
* @type Function
*/
this.fn = fn;
/**
* Optional 'this' keyword for the listener
* @property context
* @type Object
*/
this.context = context;
/**
* Unique subscriber id
* @property id
* @type String
*/
this.id = Y.stamp(this);
/**
* Additional arguments to propagate to the subscriber
* @property args
* @type Array
*/
this.args = args;
/**
* Custom events for a given fire transaction.
* @property events
* @type {EventTarget}
*/
// this.events = null;
/**
* This listener only reacts to the event once
* @property once
*/
// this.once = false;
};
Y.Subscriber.prototype = {
constructor: Y.Subscriber,
_notify: function(c, args, ce) {
if (this.deleted && !this.postponed) {
if (this.postponed) {
delete this.fn;
delete this.context;
} else {
delete this.postponed;
return null;
}
}
var a = this.args, ret;
switch (ce.signature) {
case 0:
ret = this.fn.call(c, ce.type, args, c);
break;
case 1:
ret = this.fn.call(c, args[0] || null, c);
break;
default:
if (a || args) {
args = args || [];
a = (a) ? args.concat(a) : args;
ret = this.fn.apply(c, a);
} else {
ret = this.fn.call(c);
}
}
if (this.once) {
ce._delete(this);
}
return ret;
},
/**
* Executes the subscriber.
* @method notify
* @param args {Array} Arguments array for the subscriber.
* @param ce {CustomEvent} The custom event that sent the notification.
*/
notify: function(args, ce) {
var c = this.context,
ret = true;
if (!c) {
c = (ce.contextFn) ? ce.contextFn() : ce.context;
}
// only catch errors if we will not re-throw them.
if (Y.config.throwFail) {
ret = this._notify(c, args, ce);
} else {
try {
ret = this._notify(c, args, ce);
} catch (e) {
Y.error(this + ' failed: ' + e.message, e);
}
}
return ret;
},
/**
* Returns true if the fn and obj match this objects properties.
* Used by the unsubscribe method to match the right subscriber.
*
* @method contains
* @param {Function} fn the function to execute.
* @param {Object} context optional 'this' keyword for the listener.
* @return {boolean} true if the supplied arguments match this
* subscriber's signature.
*/
contains: function(fn, context) {
if (context) {
return ((this.fn == fn) && this.context == context);
} else {
return (this.fn == fn);
}
}
};
/**
* Return value from all subscribe operations
* @class EventHandle
* @constructor
* @param {CustomEvent} evt the custom event.
* @param {Subscriber} sub the subscriber.
*/
Y.EventHandle = function(evt, sub) {
/**
* The custom event
*
* @property evt
* @type CustomEvent
*/
this.evt = evt;
/**
* The subscriber object
*
* @property sub
* @type Subscriber
*/
this.sub = sub;
};
Y.EventHandle.prototype = {
batch: function(f, c) {
f.call(c || this, this);
if (Y.Lang.isArray(this.evt)) {
Y.Array.each(this.evt, function(h) {
h.batch.call(c || h, f);
});
}
},
/**
* Detaches this subscriber
* @method detach
* @return {int} the number of detached listeners
*/
detach: function() {
var evt = this.evt, detached = 0, i;
if (evt) {
// Y.log('EventHandle.detach: ' + this.sub, 'info', 'Event');
if (Y.Lang.isArray(evt)) {
for (i = 0; i < evt.length; i++) {
detached += evt[i].detach();
}
} else {
evt._delete(this.sub);
detached = 1;
}
}
return detached;
},
/**
* Monitor the event state for the subscribed event. The first parameter
* is what should be monitored, the rest are the normal parameters when
* subscribing to an event.
* @method monitor
* @param what {string} what to monitor ('attach', 'detach', 'publish').
* @return {EventHandle} return value from the monitor event subscription.
*/
monitor: function(what) {
return this.evt.monitor.apply(this.evt, arguments);
}
};
/**
* Custom event engine, DOM event listener abstraction layer, synthetic DOM
* events.
* @module event-custom
* @submodule event-custom-base
*/
/**
* EventTarget provides the implementation for any object to
* publish, subscribe and fire to custom events, and also
* alows other EventTargets to target the object with events
* sourced from the other object.
* EventTarget is designed to be used with Y.augment to wrap
* EventCustom in an interface that allows events to be listened to
* and fired by name. This makes it possible for implementing code to
* subscribe to an event that either has not been created yet, or will
* not be created at all.
* @class EventTarget
* @param opts a configuration object
* @config emitFacade {boolean} if true, all events will emit event
* facade payloads by default (default false)
* @config prefix {String} the prefix to apply to non-prefixed event names
*/
var L = Y.Lang,
PREFIX_DELIMITER = ':',
CATEGORY_DELIMITER = '|',
AFTER_PREFIX = '~AFTER~',
YArray = Y.Array,
_wildType = Y.cached(function(type) {
return type.replace(/(.*)(:)(.*)/, "*$2$3");
}),
/**
* If the instance has a prefix attribute and the
* event type is not prefixed, the instance prefix is
* applied to the supplied type.
* @method _getType
* @private
*/
_getType = Y.cached(function(type, pre) {
if (!pre || !L.isString(type) || type.indexOf(PREFIX_DELIMITER) > -1) {
return type;
}
return pre + PREFIX_DELIMITER + type;
}),
/**
* Returns an array with the detach key (if provided),
* and the prefixed event name from _getType
* Y.on('detachcategory| menu:click', fn)
* @method _parseType
* @private
*/
_parseType = Y.cached(function(type, pre) {
var t = type, detachcategory, after, i;
if (!L.isString(t)) {
return t;
}
i = t.indexOf(AFTER_PREFIX);
if (i > -1) {
after = true;
t = t.substr(AFTER_PREFIX.length);
// Y.log(t);
}
i = t.indexOf(CATEGORY_DELIMITER);
if (i > -1) {
detachcategory = t.substr(0, (i));
t = t.substr(i+1);
if (t == '*') {
t = null;
}
}
// detach category, full type with instance prefix, is this an after listener, short type
return [detachcategory, (pre) ? _getType(t, pre) : t, after, t];
}),
ET = function(opts) {
// Y.log('EventTarget constructor executed: ' + this._yuid);
var o = (L.isObject(opts)) ? opts : {};
this._yuievt = this._yuievt || {
id: Y.guid(),
events: {},
targets: {},
config: o,
chain: ('chain' in o) ? o.chain : Y.config.chain,
bubbling: false,
defaults: {
context: o.context || this,
host: this,
emitFacade: o.emitFacade,
fireOnce: o.fireOnce,
queuable: o.queuable,
monitored: o.monitored,
broadcast: o.broadcast,
defaultTargetOnly: o.defaultTargetOnly,
bubbles: ('bubbles' in o) ? o.bubbles : true
}
};
};
ET.prototype = {
constructor: ET,
/**
* Listen to a custom event hosted by this object one time.
* This is the equivalent to <code>on</code> except the
* listener is immediatelly detached when it is executed.
* @method once
* @param {String} type The name of the event
* @param {Function} fn The callback to execute in response to the event
* @param {Object} [context] Override `this` object in callback
* @param {Any} [arg*] 0..n additional arguments to supply to the subscriber
* @return {EventHandle} A subscription handle capable of detaching the
* subscription
*/
once: function() {
var handle = this.on.apply(this, arguments);
handle.batch(function(hand) {
if (hand.sub) {
hand.sub.once = true;
}
});
return handle;
},
/**
* Listen to a custom event hosted by this object one time.
* This is the equivalent to <code>after</code> except the
* listener is immediatelly detached when it is executed.
* @method onceAfter
* @param {String} type The name of the event
* @param {Function} fn The callback to execute in response to the event
* @param {Object} [context] Override `this` object in callback
* @param {Any} [arg*] 0..n additional arguments to supply to the subscriber
* @return {EventHandle} A subscription handle capable of detaching that
* subscription
*/
onceAfter: function() {
var handle = this.after.apply(this, arguments);
handle.batch(function(hand) {
if (hand.sub) {
hand.sub.once = true;
}
});
return handle;
},
/**
* Takes the type parameter passed to 'on' and parses out the
* various pieces that could be included in the type. If the
* event type is passed without a prefix, it will be expanded
* to include the prefix one is supplied or the event target
* is configured with a default prefix.
* @method parseType
* @param {String} type the type
* @param {String} [pre=this._yuievt.config.prefix] the prefix
* @since 3.3.0
* @return {Array} an array containing:
* * the detach category, if supplied,
* * the prefixed event type,
* * whether or not this is an after listener,
* * the supplied event type
*/
parseType: function(type, pre) {
return _parseType(type, pre || this._yuievt.config.prefix);
},
/**
* Subscribe a callback function to a custom event fired by this object or
* from an object that bubbles its events to this object.
*
* Callback functions for events published with `emitFacade = true` will
* receive an `EventFacade` as the first argument (typically named "e").
* These callbacks can then call `e.preventDefault()` to disable the
* behavior published to that event's `defaultFn`. See the `EventFacade`
* API for all available properties and methods. Subscribers to
* non-`emitFacade` events will receive the arguments passed to `fire()`
* after the event name.
*
* To subscribe to multiple events at once, pass an object as the first
* argument, where the key:value pairs correspond to the eventName:callback,
* or pass an array of event names as the first argument to subscribe to
* all listed events with the same callback.
*
* Returning `false` from a callback is supported as an alternative to
* calling `e.preventDefault(); e.stopPropagation();`. However, it is
* recommended to use the event methods whenever possible.
*
* @method on
* @param {String} type The name of the event
* @param {Function} fn The callback to execute in response to the event
* @param {Object} [context] Override `this` object in callback
* @param {Any} [arg*] 0..n additional arguments to supply to the subscriber
* @return {EventHandle} A subscription handle capable of detaching that
* subscription
*/
on: function(type, fn, context) {
var parts = _parseType(type, this._yuievt.config.prefix), f, c, args, ret, ce,
detachcategory, handle, store = Y.Env.evt.handles, after, adapt, shorttype,
Node = Y.Node, n, domevent, isArr;
// full name, args, detachcategory, after
this._monitor('attach', parts[1], {
args: arguments,
category: parts[0],
after: parts[2]
});
if (L.isObject(type)) {
if (L.isFunction(type)) {
return Y.Do.before.apply(Y.Do, arguments);
}
f = fn;
c = context;
args = YArray(arguments, 0, true);
ret = [];
if (L.isArray(type)) {
isArr = true;
}
after = type._after;
delete type._after;
Y.each(type, function(v, k) {
if (L.isObject(v)) {
f = v.fn || ((L.isFunction(v)) ? v : f);
c = v.context || c;
}
var nv = (after) ? AFTER_PREFIX : '';
args[0] = nv + ((isArr) ? v : k);
args[1] = f;
args[2] = c;
ret.push(this.on.apply(this, args));
}, this);
return (this._yuievt.chain) ? this : new Y.EventHandle(ret);
}
detachcategory = parts[0];
after = parts[2];
shorttype = parts[3];
// extra redirection so we catch adaptor events too. take a look at this.
if (Node && Y.instanceOf(this, Node) && (shorttype in Node.DOM_EVENTS)) {
args = YArray(arguments, 0, true);
args.splice(2, 0, Node.getDOMNode(this));
// Y.log("Node detected, redirecting with these args: " + args);
return Y.on.apply(Y, args);
}
type = parts[1];
if (Y.instanceOf(this, YUI)) {
adapt = Y.Env.evt.plugins[type];
args = YArray(arguments, 0, true);
args[0] = shorttype;
if (Node) {
n = args[2];
if (Y.instanceOf(n, Y.NodeList)) {
n = Y.NodeList.getDOMNodes(n);
} else if (Y.instanceOf(n, Node)) {
n = Node.getDOMNode(n);
}
domevent = (shorttype in Node.DOM_EVENTS);
// Captures both DOM events and event plugins.
if (domevent) {
args[2] = n;
}
}
// check for the existance of an event adaptor
if (adapt) {
Y.log('Using adaptor for ' + shorttype + ', ' + n, 'info', 'event');
handle = adapt.on.apply(Y, args);
} else if ((!type) || domevent) {
handle = Y.Event._attach(args);
}
}
if (!handle) {
ce = this._yuievt.events[type] || this.publish(type);
handle = ce._on(fn, context, (arguments.length > 3) ? YArray(arguments, 3, true) : null, (after) ? 'after' : true);
}
if (detachcategory) {
store[detachcategory] = store[detachcategory] || {};
store[detachcategory][type] = store[detachcategory][type] || [];
store[detachcategory][type].push(handle);
}
return (this._yuievt.chain) ? this : handle;
},
/**
* subscribe to an event
* @method subscribe
* @deprecated use on
*/
subscribe: function() {
Y.log('EventTarget subscribe() is deprecated, use on()', 'warn', 'deprecated');
return this.on.apply(this, arguments);
},
/**
* Detach one or more listeners the from the specified event
* @method detach
* @param type {string|Object} Either the handle to the subscriber or the
* type of event. If the type
* is not specified, it will attempt to remove
* the listener from all hosted events.
* @param fn {Function} The subscribed function to unsubscribe, if not
* supplied, all subscribers will be removed.
* @param context {Object} The custom object passed to subscribe. This is
* optional, but if supplied will be used to
* disambiguate multiple listeners that are the same
* (e.g., you subscribe many object using a function
* that lives on the prototype)
* @return {EventTarget} the host
*/
detach: function(type, fn, context) {
var evts = this._yuievt.events, i,
Node = Y.Node, isNode = Node && (Y.instanceOf(this, Node));
// detachAll disabled on the Y instance.
if (!type && (this !== Y)) {
for (i in evts) {
if (evts.hasOwnProperty(i)) {
evts[i].detach(fn, context);
}
}
if (isNode) {
Y.Event.purgeElement(Node.getDOMNode(this));
}
return this;
}
var parts = _parseType(type, this._yuievt.config.prefix),
detachcategory = L.isArray(parts) ? parts[0] : null,
shorttype = (parts) ? parts[3] : null,
adapt, store = Y.Env.evt.handles, detachhost, cat, args,
ce,
keyDetacher = function(lcat, ltype, host) {
var handles = lcat[ltype], ce, i;
if (handles) {
for (i = handles.length - 1; i >= 0; --i) {
ce = handles[i].evt;
if (ce.host === host || ce.el === host) {
handles[i].detach();
}
}
}
};
if (detachcategory) {
cat = store[detachcategory];
type = parts[1];
detachhost = (isNode) ? Y.Node.getDOMNode(this) : this;
if (cat) {
if (type) {
keyDetacher(cat, type, detachhost);
} else {
for (i in cat) {
if (cat.hasOwnProperty(i)) {
keyDetacher(cat, i, detachhost);
}
}
}
return this;
}
// If this is an event handle, use it to detach
} else if (L.isObject(type) && type.detach) {
type.detach();
return this;
// extra redirection so we catch adaptor events too. take a look at this.
} else if (isNode && ((!shorttype) || (shorttype in Node.DOM_EVENTS))) {
args = YArray(arguments, 0, true);
args[2] = Node.getDOMNode(this);
Y.detach.apply(Y, args);
return this;
}
adapt = Y.Env.evt.plugins[shorttype];
// The YUI instance handles DOM events and adaptors
if (Y.instanceOf(this, YUI)) {
args = YArray(arguments, 0, true);
// use the adaptor specific detach code if
if (adapt && adapt.detach) {
adapt.detach.apply(Y, args);
return this;
// DOM event fork
} else if (!type || (!adapt && Node && (type in Node.DOM_EVENTS))) {
args[0] = type;
Y.Event.detach.apply(Y.Event, args);
return this;
}
}
// ce = evts[type];
ce = evts[parts[1]];
if (ce) {
ce.detach(fn, context);
}
return this;
},
/**
* detach a listener
* @method unsubscribe
* @deprecated use detach
*/
unsubscribe: function() {
Y.log('EventTarget unsubscribe() is deprecated, use detach()', 'warn', 'deprecated');
return this.detach.apply(this, arguments);
},
/**
* Removes all listeners from the specified event. If the event type
* is not specified, all listeners from all hosted custom events will
* be removed.
* @method detachAll
* @param type {String} The type, or name of the event
*/
detachAll: function(type) {
return this.detach(type);
},
/**
* Removes all listeners from the specified event. If the event type
* is not specified, all listeners from all hosted custom events will
* be removed.
* @method unsubscribeAll
* @param type {String} The type, or name of the event
* @deprecated use detachAll
*/
unsubscribeAll: function() {
Y.log('EventTarget unsubscribeAll() is deprecated, use detachAll()', 'warn', 'deprecated');
return this.detachAll.apply(this, arguments);
},
/**
* Creates a new custom event of the specified type. If a custom event
* by that name already exists, it will not be re-created. In either
* case the custom event is returned.
*
* @method publish
*
* @param type {String} the type, or name of the event
* @param opts {object} optional config params. Valid properties are:
*
* <ul>
* <li>
* 'broadcast': whether or not the YUI instance and YUI global are notified when the event is fired (false)
* </li>
* <li>
* 'bubbles': whether or not this event bubbles (true)
* Events can only bubble if emitFacade is true.
* </li>
* <li>
* 'context': the default execution context for the listeners (this)
* </li>
* <li>
* 'defaultFn': the default function to execute when this event fires if preventDefault was not called
* </li>
* <li>
* 'emitFacade': whether or not this event emits a facade (false)
* </li>
* <li>
* 'prefix': the prefix for this targets events, e.g., 'menu' in 'menu:click'
* </li>
* <li>
* 'fireOnce': if an event is configured to fire once, new subscribers after
* the fire will be notified immediately.
* </li>
* <li>
* 'async': fireOnce event listeners will fire synchronously if the event has already
* fired unless async is true.
* </li>
* <li>
* 'preventable': whether or not preventDefault() has an effect (true)
* </li>
* <li>
* 'preventedFn': a function that is executed when preventDefault is called
* </li>
* <li>
* 'queuable': whether or not this event can be queued during bubbling (false)
* </li>
* <li>
* 'silent': if silent is true, debug messages are not provided for this event.
* </li>
* <li>
* 'stoppedFn': a function that is executed when stopPropagation is called
* </li>
*
* <li>
* 'monitored': specifies whether or not this event should send notifications about
* when the event has been attached, detached, or published.
* </li>
* <li>
* 'type': the event type (valid option if not provided as the first parameter to publish)
* </li>
* </ul>
*
* @return {CustomEvent} the custom event
*
*/
publish: function(type, opts) {
var events, ce, ret, defaults,
edata = this._yuievt,
pre = edata.config.prefix;
type = (pre) ? _getType(type, pre) : type;
this._monitor('publish', type, {
args: arguments
});
if (L.isObject(type)) {
ret = {};
Y.each(type, function(v, k) {
ret[k] = this.publish(k, v || opts);
}, this);
return ret;
}
events = edata.events;
ce = events[type];
if (ce) {
// ce.log("publish applying new config to published event: '"+type+"' exists", 'info', 'event');
if (opts) {
ce.applyConfig(opts, true);
}
} else {
defaults = edata.defaults;
// apply defaults
ce = new Y.CustomEvent(type,
(opts) ? Y.merge(defaults, opts) : defaults);
events[type] = ce;
}
// make sure we turn the broadcast flag off if this
// event was published as a result of bubbling
// if (opts instanceof Y.CustomEvent) {
// events[type].broadcast = false;
// }
return events[type];
},
/**
* This is the entry point for the event monitoring system.
* You can monitor 'attach', 'detach', 'fire', and 'publish'.
* When configured, these events generate an event. click ->
* click_attach, click_detach, click_publish -- these can
* be subscribed to like other events to monitor the event
* system. Inividual published events can have monitoring
* turned on or off (publish can't be turned off before it
* it published) by setting the events 'monitor' config.
*
* @method _monitor
* @param what {String} 'attach', 'detach', 'fire', or 'publish'
* @param type {String} Name of the event being monitored
* @param o {Object} Information about the event interaction, such as
* fire() args, subscription category, publish config
* @private
*/
_monitor: function(what, type, o) {
var monitorevt, ce = this.getEvent(type);
if ((this._yuievt.config.monitored && (!ce || ce.monitored)) || (ce && ce.monitored)) {
monitorevt = type + '_' + what;
// Y.log('monitoring: ' + monitorevt);
o.monitored = what;
this.fire.call(this, monitorevt, o);
}
},
/**
* Fire a custom event by name. The callback functions will be executed
* from the context specified when the event was created, and with the
* following parameters.
*
* If the custom event object hasn't been created, then the event hasn't
* been published and it has no subscribers. For performance sake, we
* immediate exit in this case. This means the event won't bubble, so
* if the intention is that a bubble target be notified, the event must
* be published on this object first.
*
* The first argument is the event type, and any additional arguments are
* passed to the listeners as parameters. If the first of these is an
* object literal, and the event is configured to emit an event facade,
* that object is mixed into the event facade and the facade is provided
* in place of the original object.
*
* @method fire
* @param type {String|Object} The type of the event, or an object that contains
* a 'type' property.
* @param arguments {Object*} an arbitrary set of parameters to pass to
* the handler. If the first of these is an object literal and the event is
* configured to emit an event facade, the event facade will replace that
* parameter after the properties the object literal contains are copied to
* the event facade.
* @return {EventTarget} the event host
*
*/
fire: function(type) {
var typeIncluded = L.isString(type),
t = (typeIncluded) ? type : (type && type.type),
ce, ret, pre = this._yuievt.config.prefix, ce2,
args = (typeIncluded) ? YArray(arguments, 1, true) : arguments;
t = (pre) ? _getType(t, pre) : t;
this._monitor('fire', t, {
args: args
});
ce = this.getEvent(t, true);
ce2 = this.getSibling(t, ce);
if (ce2 && !ce) {
ce = this.publish(t);
}
// this event has not been published or subscribed to
if (!ce) {
if (this._yuievt.hasTargets) {
return this.bubble({ type: t }, args, this);
}
// otherwise there is nothing to be done
ret = true;
} else {
ce.sibling = ce2;
ret = ce.fire.apply(ce, args);
}
return (this._yuievt.chain) ? this : ret;
},
getSibling: function(type, ce) {
var ce2;
// delegate to *:type events if there are subscribers
if (type.indexOf(PREFIX_DELIMITER) > -1) {
type = _wildType(type);
// console.log(type);
ce2 = this.getEvent(type, true);
if (ce2) {
// console.log("GOT ONE: " + type);
ce2.applyConfig(ce);
ce2.bubbles = false;
ce2.broadcast = 0;
// ret = ce2.fire.apply(ce2, a);
}
}
return ce2;
},
/**
* Returns the custom event of the provided type has been created, a
* falsy value otherwise
* @method getEvent
* @param type {String} the type, or name of the event
* @param prefixed {String} if true, the type is prefixed already
* @return {CustomEvent} the custom event or null
*/
getEvent: function(type, prefixed) {
var pre, e;
if (!prefixed) {
pre = this._yuievt.config.prefix;
type = (pre) ? _getType(type, pre) : type;
}
e = this._yuievt.events;
return e[type] || null;
},
/**
* Subscribe to a custom event hosted by this object. The
* supplied callback will execute after any listeners add
* via the subscribe method, and after the default function,
* if configured for the event, has executed.
*
* @method after
* @param {String} type The name of the event
* @param {Function} fn The callback to execute in response to the event
* @param {Object} [context] Override `this` object in callback
* @param {Any} [arg*] 0..n additional arguments to supply to the subscriber
* @return {EventHandle} A subscription handle capable of detaching the
* subscription
*/
after: function(type, fn) {
var a = YArray(arguments, 0, true);
switch (L.type(type)) {
case 'function':
return Y.Do.after.apply(Y.Do, arguments);
case 'array':
// YArray.each(a[0], function(v) {
// v = AFTER_PREFIX + v;
// });
// break;
case 'object':
a[0]._after = true;
break;
default:
a[0] = AFTER_PREFIX + type;
}
return this.on.apply(this, a);
},
/**
* Executes the callback before a DOM event, custom event
* or method. If the first argument is a function, it
* is assumed the target is a method. For DOM and custom
* events, this is an alias for Y.on.
*
* For DOM and custom events:
* type, callback, context, 0-n arguments
*
* For methods:
* callback, object (method host), methodName, context, 0-n arguments
*
* @method before
* @return detach handle
*/
before: function() {
return this.on.apply(this, arguments);
}
};
Y.EventTarget = ET;
// make Y an event target
Y.mix(Y, ET.prototype);
ET.call(Y, { bubbles: false });
YUI.Env.globalEvents = YUI.Env.globalEvents || new ET();
/**
* Hosts YUI page level events. This is where events bubble to
* when the broadcast config is set to 2. This property is
* only available if the custom event module is loaded.
* @property Global
* @type EventTarget
* @for YUI
*/
Y.Global = YUI.Env.globalEvents;
// @TODO implement a global namespace function on Y.Global?
/**
`Y.on()` can do many things:
<ul>
<li>Subscribe to custom events `publish`ed and `fire`d from Y</li>
<li>Subscribe to custom events `publish`ed with `broadcast` 1 or 2 and
`fire`d from any object in the YUI instance sandbox</li>
<li>Subscribe to DOM events</li>
<li>Subscribe to the execution of a method on any object, effectively
treating that method as an event</li>
</ul>
For custom event subscriptions, pass the custom event name as the first argument and callback as the second. The `this` object in the callback will be `Y` unless an override is passed as the third argument.
Y.on('io:complete', function () {
Y.MyApp.updateStatus('Transaction complete');
});
To subscribe to DOM events, pass the name of a DOM event as the first argument
and a CSS selector string as the third argument after the callback function.
Alternately, the third argument can be a `Node`, `NodeList`, `HTMLElement`,
array, or simply omitted (the default is the `window` object).
Y.on('click', function (e) {
e.preventDefault();
// proceed with ajax form submission
var url = this.get('action');
...
}, '#my-form');
The `this` object in DOM event callbacks will be the `Node` targeted by the CSS
selector or other identifier.
`on()` subscribers for DOM events or custom events `publish`ed with a
`defaultFn` can prevent the default behavior with `e.preventDefault()` from the
event object passed as the first parameter to the subscription callback.
To subscribe to the execution of an object method, pass arguments corresponding to the call signature for
<a href="../classes/Do.html#methods_before">`Y.Do.before(...)`</a>.
NOTE: The formal parameter list below is for events, not for function
injection. See `Y.Do.before` for that signature.
@method on
@param {String} type DOM or custom event name
@param {Function} fn The callback to execute in response to the event
@param {Object} [context] Override `this` object in callback
@param {Any} [arg*] 0..n additional arguments to supply to the subscriber
@return {EventHandle} A subscription handle capable of detaching the
subscription
@see Do.before
@for YUI
**/
/**
Listen for an event one time. Equivalent to `on()`, except that
the listener is immediately detached when executed.
See the <a href="#methods_on">`on()` method</a> for additional subscription
options.
@see on
@method once
@param {String} type DOM or custom event name
@param {Function} fn The callback to execute in response to the event
@param {Object} [context] Override `this` object in callback
@param {Any} [arg*] 0..n additional arguments to supply to the subscriber
@return {EventHandle} A subscription handle capable of detaching the
subscription
@for YUI
**/
/**
Listen for an event one time. Equivalent to `once()`, except, like `after()`,
the subscription callback executes after all `on()` subscribers and the event's
`defaultFn` (if configured) have executed. Like `after()` if any `on()` phase
subscriber calls `e.preventDefault()`, neither the `defaultFn` nor the `after()`
subscribers will execute.
The listener is immediately detached when executed.
See the <a href="#methods_on">`on()` method</a> for additional subscription
options.
@see once
@method onceAfter
@param {String} type The custom event name
@param {Function} fn The callback to execute in response to the event
@param {Object} [context] Override `this` object in callback
@param {Any} [arg*] 0..n additional arguments to supply to the subscriber
@return {EventHandle} A subscription handle capable of detaching the
subscription
@for YUI
**/
/**
Like `on()`, this method creates a subscription to a custom event or to the
execution of a method on an object.
For events, `after()` subscribers are executed after the event's
`defaultFn` unless `e.preventDefault()` was called from an `on()` subscriber.
See the <a href="#methods_on">`on()` method</a> for additional subscription
options.
NOTE: The subscription signature shown is for events, not for function
injection. See <a href="../classes/Do.html#methods_after">`Y.Do.after`</a>
for that signature.
@see on
@see Do.after
@method after
@param {String} type The custom event name
@param {Function} fn The callback to execute in response to the event
@param {Object} [context] Override `this` object in callback
@param {Any} [args*] 0..n additional arguments to supply to the subscriber
@return {EventHandle} A subscription handle capable of detaching the
subscription
@for YUI
**/
}, '@VERSION@' ,{requires:['oop']});