/*!
* Ext JS Library 3.2.0
* Copyright(c) 2006-2010 Ext JS, Inc.
* licensing@extjs.com
* http://www.extjs.com/license
*/
/**
* @class Ext.util.Observable
*/
Ext.apply(Ext.util.Observable.prototype, function(){
// this is considered experimental (along with beforeMethod, afterMethod, removeMethodListener?)
// allows for easier interceptor and sequences, including cancelling and overwriting the return value of the call
// private
function getMethodEvent(method){
var e = (this.methodEvents = this.methodEvents ||
{})[method], returnValue, v, cancel, obj = this;
if (!e) {
this.methodEvents[method] = e = {};
e.originalFn = this[method];
e.methodName = method;
e.before = [];
e.after = [];
var makeCall = function(fn, scope, args){
if (!Ext.isEmpty(v = fn.apply(scope || obj, args))) {
if (Ext.isObject(v)) {
returnValue = !Ext.isEmpty(v.returnValue) ? v.returnValue : v;
cancel = !!v.cancel;
}
else
if (v === false) {
cancel = true;
}
else {
returnValue = v;
}
}
};
this[method] = function(){
var args = Ext.toArray(arguments);
returnValue = v = undefined;
cancel = false;
Ext.each(e.before, function(b){
makeCall(b.fn, b.scope, args);
if (cancel) {
return returnValue;
}
});
if (!Ext.isEmpty(v = e.originalFn.apply(obj, args))) {
returnValue = v;
}
Ext.each(e.after, function(a){
makeCall(a.fn, a.scope, args);
if (cancel) {
return returnValue;
}
});
return returnValue;
};
}
return e;
}
return {
// these are considered experimental
// allows for easier interceptor and sequences, including cancelling and overwriting the return value of the call
// adds an 'interceptor' called before the original method
beforeMethod : function(method, fn, scope){
getMethodEvent.call(this, method).before.push({
fn: fn,
scope: scope
});
},
// adds a 'sequence' called after the original method
afterMethod : function(method, fn, scope){
getMethodEvent.call(this, method).after.push({
fn: fn,
scope: scope
});
},
removeMethodListener: function(method, fn, scope){
var e = getMethodEvent.call(this, method), found = false;
Ext.each(e.before, function(b, i, arr){
if (b.fn == fn && b.scope == scope) {
arr.splice(i, 1);
found = true;
return false;
}
});
if (!found) {
Ext.each(e.after, function(a, i, arr){
if (a.fn == fn && a.scope == scope) {
arr.splice(i, 1);
return false;
}
});
}
},
/**
* Relays selected events from the specified Observable as if the events were fired by this.
* @param {Object} o The Observable whose events this object is to relay.
* @param {Array} events Array of event names to relay.
*/
relayEvents : function(o, events){
var me = this;
function createHandler(ename){
return function(){
return me.fireEvent.apply(me, [ename].concat(Ext.toArray(arguments)));
};
}
Ext.each(events, function(ename){
me.events[ename] = me.events[ename] || true;
o.on(ename, createHandler(ename), me);
});
},
/**
* Enables events fired by this Observable to bubble up an owner hierarchy by calling
* this.getBubbleTarget() if present. There is no implementation in the Observable base class.
* This is commonly used by Ext.Components to bubble events to owner Containers. See {@link Ext.Component.getBubbleTarget}. The default
* implementation in Ext.Component returns the Component's immediate owner. But if a known target is required, this can be overridden to
* access the required target more quickly.
* Example:
Ext.override(Ext.form.Field, {
// Add functionality to Field's initComponent to enable the change event to bubble
initComponent : Ext.form.Field.prototype.initComponent.createSequence(function() {
this.enableBubble('change');
}),
// We know that we want Field's events to bubble directly to the FormPanel.
getBubbleTarget : function() {
if (!this.formPanel) {
this.formPanel = this.findParentByType('form');
}
return this.formPanel;
}
});
var myForm = new Ext.formPanel({
title: 'User Details',
items: [{
...
}],
listeners: {
change: function() {
// Title goes red if form has been modified.
myForm.header.setStyle('color', 'red');
}
}
});
* @param {String/Array} events The event name to bubble, or an Array of event names.
*/
enableBubble : function(events){
var me = this;
if(!Ext.isEmpty(events)){
events = Ext.isArray(events) ? events : Ext.toArray(arguments);
Ext.each(events, function(ename){
ename = ename.toLowerCase();
var ce = me.events[ename] || true;
if (Ext.isBoolean(ce)) {
ce = new Ext.util.Event(me, ename);
me.events[ename] = ce;
}
ce.bubble = true;
});
}
}
};
}());
/**
* Starts capture on the specified Observable. All events will be passed
* to the supplied function with the event name + standard signature of the event
* before the event is fired. If the supplied function returns false,
* the event will not fire.
* @param {Observable} o The Observable to capture events from.
* @param {Function} fn The function to call when an event is fired.
* @param {Object} scope (optional) The scope (this reference) in which the function is executed. Defaults to the Observable firing the event.
* @static
*/
Ext.util.Observable.capture = function(o, fn, scope){
o.fireEvent = o.fireEvent.createInterceptor(fn, scope);
};
/**
* Sets observability on the passed class constructor.
*
This makes any event fired on any instance of the passed class also fire a single event through
* the class allowing for central handling of events on many instances at once.
* Usage:
Ext.util.Observable.observeClass(Ext.data.Connection);
Ext.data.Connection.on('beforerequest', function(con, options) {
console.log('Ajax request made to ' + options.url);
});
* @param {Function} c The class constructor to make observable.
* @param {Object} listeners An object containing a series of listeners to add. See {@link #addListener}.
* @static
*/
Ext.util.Observable.observeClass = function(c, listeners){
if(c){
if(!c.fireEvent){
Ext.apply(c, new Ext.util.Observable());
Ext.util.Observable.capture(c.prototype, c.fireEvent, c);
}
if(Ext.isObject(listeners)){
c.on(listeners);
}
return c;
}
};