/ajax_helper/media/js/backbone.js
JavaScript | 623 lines | 390 code | 77 blank | 156 comment | 106 complexity | fb90bc3fb5b00260e2ec0bb5b6370d16 MD5 | raw file
- // (c) 2010 Jeremy Ashkenas, DocumentCloud Inc.
- // Backbone may be freely distributed under the MIT license.
- // For all details and documentation:
- // http://documentcloud.github.com/backbone
- (function(){
- // Initial Setup
- // -------------
- // The top-level namespace.
- var Backbone = {};
- // Keep the version here in sync with `package.json`.
- Backbone.VERSION = '0.1.1';
- // Export for both CommonJS and the browser.
- (typeof exports !== 'undefined' ? exports : this).Backbone = Backbone;
- // Require Underscore, if we're on the server, and it's not already present.
- var _ = this._;
- if (!_ && (typeof require !== 'undefined')) _ = require("underscore")._;
- // For Backbone's purposes, jQuery owns the `$` variable.
- var $ = this.$;
- // Helper function to correctly set up the prototype chain, for subclasses.
- // Similar to `goog.inherits`, but uses a hash of prototype properties and
- // class properties to be extended.
- var inherits = function(parent, protoProps, classProps) {
- var child = protoProps.hasOwnProperty('constructor') ? protoProps.constructor :
- function(){ return parent.apply(this, arguments); };
- var ctor = function(){};
- ctor.prototype = parent.prototype;
- child.prototype = new ctor();
- _.extend(child.prototype, protoProps);
- if (classProps) _.extend(child, classProps);
- child.prototype.constructor = child;
- return child;
- };
- // Helper function to get a URL from a Model or Collection as a property
- // or as a function.
- var getUrl = function(object) {
- return _.isFunction(object.url) ? object.url() : object.url;
- };
- // Backbone.Events
- // -----------------
- // A module that can be mixed in to *any object* in order to provide it with
- // custom events. You may `bind` or `unbind` a callback function to an event;
- // `trigger`-ing an event fires all callbacks in succession.
- //
- // var object = {};
- // _.extend(object, Backbone.Events);
- // object.bind('expand', function(){ alert('expanded'); });
- // object.trigger('expand');
- //
- Backbone.Events = {
- // Bind an event, specified by a string name, `ev`, to a `callback` function.
- // Passing `"all"` will bind the callback to all events fired.
- bind : function(ev, callback) {
- var calls = this._callbacks || (this._callbacks = {});
- var list = this._callbacks[ev] || (this._callbacks[ev] = []);
- list.push(callback);
- return this;
- },
- // Remove one or many callbacks. If `callback` is null, removes all
- // callbacks for the event. If `ev` is null, removes all bound callbacks
- // for all events.
- unbind : function(ev, callback) {
- var calls;
- if (!ev) {
- this._callbacks = {};
- } else if (calls = this._callbacks) {
- if (!callback) {
- calls[ev] = [];
- } else {
- var list = calls[ev];
- if (!list) return this;
- for (var i = 0, l = list.length; i < l; i++) {
- if (callback === list[i]) {
- list.splice(i, 1);
- break;
- }
- }
- }
- }
- return this;
- },
- // Trigger an event, firing all bound callbacks. Callbacks are passed the
- // same arguments as `trigger` is, apart from the event name.
- // Listening for `"all"` passes the true event name as the first argument.
- trigger : function(ev) {
- var list, calls, i, l;
- var calls = this._callbacks;
- if (!(calls = this._callbacks)) return this;
- if (list = calls[ev]) {
- for (i = 0, l = list.length; i < l; i++) {
- list[i].apply(this, _.rest(arguments));
- }
- }
- if (list = calls['all']) {
- for (i = 0, l = list.length; i < l; i++) {
- list[i].apply(this, arguments);
- }
- }
- return this;
- }
- };
- // Backbone.Model
- // --------------
- // Create a new model, with defined attributes. A client id (`cid`)
- // is automatically generated and assigned for you.
- Backbone.Model = function(attributes) {
- this.attributes = {};
- this.cid = _.uniqueId('c');
- this.set(attributes || {}, {silent : true});
- this._previousAttributes = _.clone(this.attributes);
- if (this.initialize) this.initialize(attributes);
- };
- // Attach all inheritable methods to the Model prototype.
- _.extend(Backbone.Model.prototype, Backbone.Events, {
- // A snapshot of the model's previous attributes, taken immediately
- // after the last `changed` event was fired.
- _previousAttributes : null,
- // Has the item been changed since the last `changed` event?
- _changed : false,
- // Return a copy of the model's `attributes` object.
- toJSON : function() {
- return _.clone(this.attributes);
- },
- // Get the value of an attribute.
- get : function(attr) {
- return this.attributes[attr];
- },
- // Set a hash of model attributes on the object, firing `changed` unless you
- // choose to silence it.
- set : function(attrs, options) {
- // Extract attributes and options.
- options || (options = {});
- if (!attrs) return this;
- attrs = attrs.attributes || attrs;
- var now = this.attributes;
- // Run validation if `validate` is defined.
- if (this.validate) {
- var error = this.validate(attrs);
- if (error) {
- this.trigger('error', this, error);
- return false;
- }
- }
- // Check for changes of `id`.
- if ('id' in attrs) this.id = attrs.id;
- // Update attributes.
- for (var attr in attrs) {
- var val = attrs[attr];
- if (val === '') val = null;
- if (!_.isEqual(now[attr], val)) {
- now[attr] = val;
- if (!options.silent) {
- this._changed = true;
- this.trigger('change:' + attr, this, val);
- }
- }
- }
- // Fire the `change` event, if the model has been changed.
- if (!options.silent && this._changed) this.change();
- return this;
- },
- // Remove an attribute from the model, firing `changed` unless you choose to
- // silence it.
- unset : function(attr, options) {
- options || (options = {});
- var value = this.attributes[attr];
- delete this.attributes[attr];
- if (!options.silent) {
- this._changed = true;
- this.trigger('change:' + attr, this);
- this.change();
- }
- return value;
- },
- // Set a hash of model attributes, and sync the model to the server.
- // If the server returns an attributes hash that differs, the model's
- // state will be `set` again.
- save : function(attrs, options) {
- attrs || (attrs = {});
- options || (options = {});
- if (!this.set(attrs, options)) return false;
- var model = this;
- var success = function(resp) {
- if (!model.set(resp.model)) return false;
- if (options.success) options.success(model, resp);
- };
- var method = this.isNew() ? 'create' : 'update';
- Backbone.sync(method, this, success, options.error);
- return this;
- },
- // Destroy this model on the server. Upon success, the model is removed
- // from its collection, if it has one.
- destroy : function(options) {
- options || (options = {});
- var model = this;
- var success = function(resp) {
- if (model.collection) model.collection.remove(model);
- if (options.success) options.success(model, resp);
- };
- Backbone.sync('delete', this, success, options.error);
- return this;
- },
- // Default URL for the model's representation on the server -- if you're
- // using Backbone's restful methods, override this to change the endpoint
- // that will be called.
- url : function() {
- var base = getUrl(this.collection);
- if (this.isNew()) return base;
- return base + '/' + this.id;
- },
- // Create a new model with identical attributes to this one.
- clone : function() {
- return new this.constructor(this);
- },
- // A model is new if it has never been saved to the server, and has a negative
- // ID.
- isNew : function() {
- return !this.id;
- },
- // Call this method to fire manually fire a `change` event for this model.
- // Calling this will cause all objects observing the model to update.
- change : function() {
- this.trigger('change', this);
- this._previousAttributes = _.clone(this.attributes);
- this._changed = false;
- },
- // Determine if the model has changed since the last `changed` event.
- // If you specify an attribute name, determine if that attribute has changed.
- hasChanged : function(attr) {
- if (attr) return this._previousAttributes[attr] != this.attributes[attr];
- return this._changed;
- },
- // Return an object containing all the attributes that have changed, or false
- // if there are no changed attributes. Useful for determining what parts of a
- // view need to be updated and/or what attributes need to be persisted to
- // the server.
- changedAttributes : function(now) {
- var old = this._previousAttributes, now = now || this.attributes, changed = false;
- for (var attr in now) {
- if (!_.isEqual(old[attr], now[attr])) {
- changed = changed || {};
- changed[attr] = now[attr];
- }
- }
- return changed;
- },
- // Get the previous value of an attribute, recorded at the time the last
- // `changed` event was fired.
- previous : function(attr) {
- if (!attr || !this._previousAttributes) return null;
- return this._previousAttributes[attr];
- },
- // Get all of the attributes of the model at the time of the previous
- // `changed` event.
- previousAttributes : function() {
- return _.clone(this._previousAttributes);
- }
- });
- // Backbone.Collection
- // -------------------
- // Provides a standard collection class for our sets of models, ordered
- // or unordered. If a `comparator` is specified, the Collection will maintain
- // its models in sort order, as they're added and removed.
- Backbone.Collection = function(models, options) {
- options || (options = {});
- if (options.comparator) {
- this.comparator = options.comparator;
- delete options.comparator;
- }
- this._boundOnModelEvent = _.bind(this._onModelEvent, this);
- this._reset();
- if (models) this.refresh(models, {silent: true});
- if (this.initialize) this.initialize(models, options);
- };
- // Define the Collection's inheritable methods.
- _.extend(Backbone.Collection.prototype, Backbone.Events, {
- model : Backbone.Model,
- // Add a model, or list of models to the set. Pass **silent** to avoid
- // firing the `added` event for every new model.
- add : function(models, options) {
- if (!_.isArray(models)) return this._add(models, options);
- for (var i=0; i<models.length; i++) this._add(models[i], options);
- return models;
- },
- // Remove a model, or a list of models from the set. Pass silent to avoid
- // firing the `removed` event for every model removed.
- remove : function(models, options) {
- if (!_.isArray(models)) return this._remove(models, options);
- for (var i=0; i<models.length; i++) this._remove(models[i], options);
- return models;
- },
- // Get a model from the set by id.
- get : function(id) {
- return id && this._byId[id.id != null ? id.id : id];
- },
- // Get a model from the set by client id.
- getByCid : function(cid) {
- return cid && this._byCid[cid.cid || cid];
- },
- // Get the model at the given index.
- at: function(index) {
- return this.models[index];
- },
- // Force the collection to re-sort itself. You don't need to call this under normal
- // circumstances, as the set will maintain sort order as each item is added.
- sort : function(options) {
- options || (options = {});
- if (!this.comparator) throw new Error('Cannot sort a set without a comparator');
- this.models = this.sortBy(this.comparator);
- if (!options.silent) this.trigger('refresh', this);
- return this;
- },
- // Pluck an attribute from each model in the collection.
- pluck : function(attr) {
- return _.map(this.models, function(model){ return model.get(attr); });
- },
- // When you have more items than you want to add or remove individually,
- // you can refresh the entire set with a new list of models, without firing
- // any `added` or `removed` events. Fires `refresh` when finished.
- refresh : function(models, options) {
- options || (options = {});
- models = models || [];
- var collection = this;
- if (models[0] && !(models[0] instanceof Backbone.Model)) {
- models = _.map(models, function(attrs, i) {
- return new collection.model(attrs);
- });
- }
- this._reset();
- this.add(models, {silent: true});
- if (!options.silent) this.trigger('refresh', this);
- return this;
- },
- // Fetch the default set of models for this collection, refreshing the
- // collection when they arrive.
- fetch : function(options) {
- options || (options = {});
- var collection = this;
- var success = function(resp) {
- collection.refresh(resp.models);
- if (options.success) options.success(collection, resp);
- };
- Backbone.sync('read', this, success, options.error);
- return this;
- },
- // Create a new instance of a model in this collection. After the model
- // has been created on the server, it will be added to the collection.
- create : function(model, options) {
- options || (options = {});
- if (!(model instanceof Backbone.Model)) model = new this.model(model);
- model.collection = this;
- var success = function(resp) {
- if (!model.set(resp.model)) return false;
- model.collection.add(model);
- if (options.success) options.success(model, resp);
- };
- return model.save(null, {success : success, error : options.error});
- },
- // Reset all internal state. Called when the collection is refreshed.
- _reset : function(options) {
- this.length = 0;
- this.models = [];
- this._byId = {};
- this._byCid = {};
- },
- // Internal implementation of adding a single model to the set, updating
- // hash indexes for `id` and `cid` lookups.
- _add : function(model, options) {
- options || (options = {});
- var already = this.get(model);
- if (already) throw new Error(["Can't add the same model to a set twice", already.id]);
- this._byId[model.id] = model;
- this._byCid[model.cid] = model;
- model.collection = this;
- var index = this.comparator ? this.sortedIndex(model, this.comparator) : this.length;
- this.models.splice(index, 0, model);
- model.bind('all', this._boundOnModelEvent);
- this.length++;
- if (!options.silent) this.trigger('add', model);
- return model;
- },
- // Internal implementation of removing a single model from the set, updating
- // hash indexes for `id` and `cid` lookups.
- _remove : function(model, options) {
- options || (options = {});
- model = this.get(model);
- if (!model) return null;
- delete this._byId[model.id];
- delete this._byCid[model.cid];
- delete model.collection;
- this.models.splice(this.indexOf(model), 1);
- model.unbind('all', this._boundOnModelEvent);
- this.length--;
- if (!options.silent) this.trigger('remove', model);
- return model;
- },
- // Internal method called every time a model in the set fires an event.
- // Sets need to update their indexes when models change ids.
- _onModelEvent : function(ev, model, error) {
- switch (ev) {
- case 'change':
- if (model.hasChanged('id')) {
- delete this._byId[model.previous('id')];
- this._byId[model.id] = model;
- }
- this.trigger('change', model);
- break;
- case 'error':
- this.trigger('error', model, error);
- }
- }
- });
- // Underscore methods that we want to implement on the Collection.
- var methods = ['forEach', 'each', 'map', 'reduce', 'reduceRight', 'find', 'detect',
- 'filter', 'select', 'reject', 'every', 'all', 'some', 'any', 'include',
- 'invoke', 'max', 'min', 'sortBy', 'sortedIndex', 'toArray', 'size',
- 'first', 'rest', 'last', 'without', 'indexOf', 'lastIndexOf', 'isEmpty'];
- // Mix in each Underscore method as a proxy to `Collection#models`.
- _.each(methods, function(method) {
- Backbone.Collection.prototype[method] = function() {
- return _[method].apply(_, [this.models].concat(_.toArray(arguments)));
- };
- });
- // Backbone.View
- // -------------
- // Creating a Backbone.View creates its initial element outside of the DOM,
- // if an existing element is not provided...
- Backbone.View = function(options) {
- this._configure(options || {});
- if (this.options.el) {
- this.el = this.options.el;
- } else {
- var attrs = {};
- if (this.id) attrs.id = this.id;
- if (this.className) attrs.className = this.className;
- this.el = this.make(this.tagName, attrs);
- }
- if (this.initialize) this.initialize(options);
- };
- // jQuery lookup, scoped to DOM elements within the current view.
- // This should be prefered to global jQuery lookups, if you're dealing with
- // a specific view.
- var jQueryDelegate = function(selector) {
- return $(selector, this.el);
- };
- // Cached regex to split keys for `handleEvents`.
- var eventSplitter = /^(\w+)\s*(.*)$/;
- // Set up all inheritable **Backbone.View** properties and methods.
- _.extend(Backbone.View.prototype, {
- // The default `tagName` of a View's element is `"div"`.
- tagName : 'div',
- // Attach the jQuery function as the `$` and `jQuery` properties.
- $ : jQueryDelegate,
- jQuery : jQueryDelegate,
- // **render** is the core function that your view should override, in order
- // to populate its element (`this.el`), with the appropriate HTML. The
- // convention is for **render** to always return `this`.
- render : function() {
- return this;
- },
- // For small amounts of DOM Elements, where a full-blown template isn't
- // needed, use **make** to manufacture elements, one at a time.
- //
- // var el = this.make('li', {'class': 'row'}, this.model.get('title'));
- //
- make : function(tagName, attributes, content) {
- var el = document.createElement(tagName);
- if (attributes) $(el).attr(attributes);
- if (content) $(el).html(content);
- return el;
- },
- // Set callbacks, where `this.callbacks` is a hash of
- //
- // *{"event selector": "callback"}*
- //
- // {
- // 'mousedown .title': 'edit',
- // 'click .button': 'save'
- // }
- //
- // pairs. Callbacks will be bound to the view, with `this` set properly.
- // Uses jQuery event delegation for efficiency.
- // Omitting the selector binds the event to `this.el`.
- // `"change"` events are not delegated through the view because IE does not
- // bubble change events at all.
- handleEvents : function(events) {
- $(this.el).unbind();
- if (!(events || (events = this.events))) return this;
- for (key in events) {
- var methodName = events[key];
- var match = key.match(eventSplitter);
- var eventName = match[1], selector = match[2];
- var method = _.bind(this[methodName], this);
- if (selector === '' || eventName == 'change') {
- $(this.el).bind(eventName, method);
- } else {
- $(this.el).delegate(selector, eventName, method);
- }
- }
- return this;
- },
- // Performs the initial configuration of a View with a set of options.
- // Keys with special meaning *(model, collection, id, className)*, are
- // attached directly to the view.
- _configure : function(options) {
- if (this.options) options = _.extend({}, this.options, options);
- if (options.model) this.model = options.model;
- if (options.collection) this.collection = options.collection;
- if (options.id) this.id = options.id;
- if (options.className) this.className = options.className;
- if (options.tagName) this.tagName = options.tagName;
- this.options = options;
- }
- });
- // Set up inheritance for the model, collection, and view.
- var extend = Backbone.Model.extend = Backbone.Collection.extend = Backbone.View.extend = function (protoProps, classProps) {
- var child = inherits(this, protoProps, classProps);
- child.extend = extend;
- return child;
- };
- // Map from CRUD to HTTP for our default `Backbone.sync` implementation.
- var methodMap = {
- 'create': 'POST',
- 'update': 'PUT',
- 'delete': 'DELETE',
- 'read' : 'GET'
- };
- // Override this function to change the manner in which Backbone persists
- // models to the server. You will be passed the type of request, and the
- // model in question. By default, uses jQuery to make a RESTful Ajax request
- // to the model's `url()`. Some possible customizations could be:
- //
- // * Use `setTimeout` to batch rapid-fire updates into a single request.
- // * Send up the models as XML instead of JSON.
- // * Persist models via WebSockets instead of Ajax.
- //
- Backbone.sync = function(method, model, success, error) {
- $.ajax({
- url : getUrl(model),
- type : methodMap[method],
- data : {model : JSON.stringify(model)},
- dataType : 'json',
- success : success,
- error : error
- });
- };
- })();