/*! * Ext JS Library 3.0.3 * Copyright(c) 2006-2009 Ext JS, LLC * 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:
* @param {Object} 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 * @param {Function} fn The function to call * @param {Object} scope (optional) The scope (this object) for the fn * @static */ Ext.util.Observable.capture = function(o, fn, scope){ o.fireEvent = o.fireEvent.createInterceptor(fn, scope); }; /** * Sets observability on the passed class constructor.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"); } } });
*
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:
* @param {Function} c The class constructor to make observable. * @static */ Ext.util.Observable.observeClass = function(c){ Ext.apply(c, new Ext.util.Observable()); c.prototype.fireEvent = function(){ return (c.fireEvent.apply(c, arguments) !== false) && (Ext.util.Observable.prototype.fireEvent.apply(this, arguments) !== false); }; };Ext.util.Observable.observeClass(Ext.data.Connection); Ext.data.Connection.on('beforerequest', function(con, options) { console.log("Ajax request made to " + options.url); });