JavaScript 学习笔记十 练习任务系统//开发一个任务系统，我们需要抽象出一个类来表示任务，对应的，//每个任
JavaScript 学习笔记十 练习任务系统
//开发一个任务系统，我们需要抽象出一个类来表示任务，对应的，//每个任务都可能会有一个监听器，当任务执行之后，需要通知监听器。//监听器的类var EventListener = Base.extend({ constructor : function(sense){ this.sense =sense; }, sense : null, handle : function(){ logs(this.sense+" occured"); }});//任务类var Task = Base.extend({ constructor : function(name){ this.name = name; }, name : null, listener : null, execute : function(){ logs(this.name); this.listener.handle(); }, setListener : function(listener){ this.listener = listener; }});//创建类的方式很简单，需要给 Base.extend 方法传入一个 JSON 对象//方法访问自身的成员时需要加 this 关键字var pri = new Task("定时任务1");var priListen = new EventListener("监听器1");pri.setListener(priListen);pri.execute();//打印如下: //定时任务1 //监听器1 occured?
var Base = function() {};Base.prototype = {extend : function(source) {if (arguments.length > 1) { var ancestor = this[source];var value = arguments[1];if (typeof value == "function" && ancestor&& /\bbase\b/.test(value)) {var method = value;value = function() {var previous = this.base;this.base = ancestor;var returnValue = method.apply(this, arguments);this.base = previous;return returnValue;};value.method = method;value.ancestor = ancestor;}this[source] = value;} else if (source) { var extend = Base.prototype.extend;if (Base._prototyping) {var key, i = 0, members = ["constructor", "toString", "valueOf"];while (key = members[i++]) {if (source[key] != Object.prototype[key]) {extend.call(this, key, source[key]);}}} else if (typeof this != "function") {extend = this.extend || extend;}for (key in source)if (!Object.prototype[key]) {extend.call(this, key, source[key]);}}return this;},base : Base};Base.extend = function(_instance, _static) { var extend = Base.prototype.extend;Base._prototyping = true;var proto = new this;extend.call(proto, _instance);delete Base._prototyping;var constructor = proto.constructor;var klass = proto.constructor = function() {if (!Base._prototyping) {if (this._constructing || this.constructor == klass) { this._constructing = true;constructor.apply(this, arguments);delete this._constructing;}else { var object = arguments[0];if (object != null) {(object.extend || extend).call(object, proto);}return object;}}};for (var i in Base) {klass[i] = this[i];}klass.ancestor = this;klass.base = Base.base;klass.prototype = proto;klass.toString = this.toString;extend.call(klass, _static);if (typeof klass.init == "function")klass.init();return klass;};Base = Base.extend({constructor : function() {this.extend(arguments[0]);} }, {ancestor : Object,base : Base,implement : function(_interface) {if (typeof _interface == "function") {_interface(this.prototype);} else {this.prototype.extend(_interface);}return this;} });