Given the following code:
JE.events = {
self: this,
controller: {
init: function(){
$(".monthheader").click(function () {
JE.events.model.get($(this).attr('title'));
return false;
});
return this;
}
},
model: {
get: function(monthnum){
...
}
}
}
How would i replace the call to
JE.events.model.get(..);
by something like
self.model.get(..);
The whole code is more or less in this gist https://gist.github.com/966270 . The idea is to create a really simple MVC in js (my first attempt) that i can reuse easily. Improvements are welcome!
JE.events = (function {
// Create closure
// Declare controller and model as local
var Controller = {
init: function(){
$(".monthheader").click(function () {
Model.get($(this).attr('title'));
return false;
});
return this;
}
}
var Model = {
get: function(monthnum){
...
}
}
// return object thats assigned to JE.events
return {
controller: Controller,
model: Model
}
)();
You may also want to look at backbone or spine which are lightweight MVC frameworks.
They give you some simple abstractions and a lot of control. There also small and simple.
If I were to write a micro MVC framework from scratch it would converge to either backbone or spine so it might be better to use one of those two.
Related
I am using Durandal 2.1, and I am having a problem with view composition. I have a view for managing many types of items. I also want a view to manage a subset of those types. So I created a manage view and a managesubset view. The managesubset view just composes the manage view and passes it an array containing the subset of items. This way the user can go to /100/manage or 100/managesubset where managesubset will only allow the user to manage a subset of items. I am using this pattern because I will have multiple different versions of managesubset.
My problem is that the canDeactivate method is not fired when going to managesubset. Is there anyway to fire the canDeactivate and Deactivate lifecycle events when composing?
According to #3 under Activator Lifecycle Callbacks here, I should be able to do this, but I cannot find any good examples.
Code:
manage.js
define(['durandal/app', 'plugins/router'], function (app, router) {
var constructor = function () {
var self = this;
//...variable creation and assignment
//life cycle events
self.activate = function (viewmodel) {
self.recordId(viewmodel.recordId);
self.assignableTypes(viewmodel.assignableTypes);
self.pageHeaderTitle = viewmodel.pageHeaderTitle;
self.pageHeaderIcon = viewmodel.pageHeaderIcon;
};
self.canActivate = function (id) {
var deferred = $.Deferred();
//check if user has access to manage equipment
};
self.canDeactivate = function () {
if (!self.saveSuccessfull() && this.isDirty()) {
return app.showMessage("You have unsaved changes, are you sure you want to leave?", "Unsaved Changes", ["Yes", "No"]);
}
else {
return true;
}
}
};
return constructor;
});
managesubset.js
define([], function () {
var recordId = ko.observable();
var manageRecord = ko.observable();
return {
recordId: recordId,
manageRecord: manageRecord,
activate: function (id) {
recordId(id);
manageRecord({
pageHeaderTitle: 'Manage Subset',
pageHeaderIcon: 'cb-subset',
assignableTypes: [102],
recordId: recordId()
});
},
canActivate: function (id) {
var deferred = $.Deferred();
//check if user has access to manage equipment
}
}
});
managesubset.html
<div data-bind="compose: { model: 'manage', activationData: manageRecord() }"></div>
The activate is called correctly each time. The deactivate and canDeactive are what don't work, and they are never called.
I am trying to figure out how to use a custom view location strategy, I have read the documentation at this page http://durandaljs.com/documentation/Using-Composition/ but I don't exactly understand what the strategy function should look like.
Can anybody give me a quick example of what the implementation of this function would be like and the promise that returns (even a simple one) etc?
Thanks in advance,
Gary
p.s. This is the code in my html:
<div>
<div data-bind="compose: {model: 'viewmodels/childRouter/first/simpleModel', strategy:
'viewmodels/childRouter/first/myCustomViewStrategy'}"></div> </div>
and this is the code in my myCustomViewStrategy:
define(function () {
var myCustomViewStrategy = function () {
var deferred = $.Deferred();
deferred.done(function () { console.log('done'); return 'simpleModelView'; });
deferred.fail(function () { console.log('error'); });
setTimeout(function () { deferred.resolve('done'); }, 5000);
return deferred.promise();
};
return myCustomViewStrategy;
});
but I get the error:
Uncaught TypeError: Cannot read property 'display' of undefined - this is after done has been logged in the console window.
Okay I solved this by creating my custom view strategy by the following:
define(['durandal/system', 'durandal/viewEngine'], function (system, viewEngine) {
var myCustomViewStrategy = function () {
return viewEngine.createView('views/childRouter/first/sModelView');
}
return myCustomViewStrategy;
});
As I found the documentation a bit lacking on compose binding's strategy setting I checked the source code how it works. To summ it up:
The module specified by the compose binding's strategy setting by its moduleId
must return a function named 'strategy'
which returns a promise which results in the view to be bound
as a HTML element object.
As a parameter the strategy method receives the compose binding's settings object
with the model object already resolved.
A working example:
define(['durandal/system', 'durandal/viewEngine'], function (system, viewEngine) {
var strategy = function(settings){
var viewid = null;
if(settings.model){
// replaces model's module id's last segment ('/viewmodel') with '/view'
viewid = settings.model.__moduleId__.replace(/\/[^\/]*$/, '/view');
}
return viewEngine.createView(viewid);
};
return strategy;
});
Durandal's source:
// composition.js:485
for (var attrName in settings) {
if (ko.utils.arrayIndexOf(bindableSettings, attrName) != -1) {
/*
* strategy is unwrapped
*/
settings[attrName] = ko.utils.unwrapObservable(settings[attrName]);
} else {
settings[attrName] = settings[attrName];
}
}
// composition.js:523
if (system.isString(context.strategy)) {
/*
* strategy is loaded
*/
system.acquire(context.strategy).then(function (strategy) {
context.strategy = strategy;
composition.executeStrategy(context);
}).fail(function(err){
system.error('Failed to load view strategy (' + context.strategy + '). Details: ' + err.message);
});
} else {
this.executeStrategy(context);
}
// composition.js:501
executeStrategy: function (context) {
/*
* strategy is executed
* expected to be a promise
* which returns the view to be bound and inserted to the DOM
*/
context.strategy(context).then(function (child) {
composition.bindAndShow(child, context);
});
}
I have a Rails/AngularJS app which works fine in local development environment.
However, when I deploy this app to Heroku the AngularJS doesn't work an returns this error:
Unknown provider: eProvider <- e
I did a bit of research and it seems it has something to do with the precompiling and minification of the assets, but I don't know what to do to solve this. Any ideas? Thanks!
This is how the controller looks:
function RemindersCtrl($scope, $http) {
$http.get('/reminders.json').success(function(data) {
$scope.reminders = data;
console.log(data);
});
}
And this is the code in the view:
%section.reminders
%div{"ng-controller" => "RemindersCtrl"}
%ul
%li{"ng-repeat" => "reminder in reminders"}
.title {{reminder.title}}
Update: I changed the controller to this, but with the same result:
var RemindersCtrl = function($scope, $http) {
$http.get('/reminders.json').success(function(data) {
$scope.reminders = data;
console.log(data);
});
}
RemindersCtrl.$inject = ['$scope','$http'];
According to AngularJS tutorial (http://docs.angularjs.org/tutorial/step_05) you can either add this to the controller to prevent minification problems:
function RemindersCtrl($scope, $http) {
...
}
RemindersCtrl.$inject = ['$scope', '$http'];
or instead of defining a function like this:
function RemindersCtrl($scope, $http) {
...
}
it should be done like this:
var RemindersCtrl = ['$scope', '$http', function($scope, $http) {
...
}];
You are probably defining your controller as FooController = function($http) {}, you should define as FooController = ["$http", function($http){}]
See mroe here
Angular team (and also generally speaking) recommends that we do not pollute the global scope.
.controller method,
var myApp = angular.module('myApp',[]);
myApp.controller('GreetingCtrl', ['$scope', function($scope) {
$scope.greeting = 'Hola!';
}]);
worked fine for me. This is documented on Angular Understanding Controllers documentation
I am actually playing with Javascript doing a small game and I would like to implement what I've found on http://www.crockford.com/javascript/inheritance.html which is something similar to:
ZParenizor.method('toString', function () {
if (this.getValue()) {
return this.uber('toString');
}
return "-0-";
});
I can't find any reference the the library used to make such development possible. Any ideas? Otherwise, I'm looking for a good library that will aid my OOP developments.
Thank you
Edit:
I am looking for a OOP solution / library for Node.js. Please note that I'm new to Node.js
2 months later
Maybe you do need a library, ES5 is verbose as hell so I've created pd
Original answer
I am looking for a OOP solution / library for Node.js.
You don't need a library. You have ES5.
JavaScript does not have classical OOP. It has prototyping OOP.
This means you have only objects. The only thing you can do with objects is extend, manipulate and clone them.
Manipulate
var o = {};
o.foo = "bar";
Extend
var o = someObject;
Object.defineProperties(o, {
"foo": { value: "foo" },
"bar": { value: "bar" }
"method": { value: function () { } }
}
Clone
var o = someObject;
var p = Object.create(o);
Clone and extend
var o = someObject;
var p = Object.create(o, {
"foo": { value: "foo" },
"bar": { value: "bar" }
"method": { value: function () { } }
}
It's important to understand how Object.create, Object.defineProperty and Object.defineProperties work.
The cloning operation isn't actually cloning. It's creating a new object from a blueprint. A blueprint is an object. It places the blueprint in the [[Prototype]]. The [[Prototype]] lives in the .__proto__ property which I'll use for demonstration.
var o = {};
var p = Object.create(o);
p.__proto__ === o; // true
var q = Object.create(p);
q.__proto__.__proto__ === o;
var r = Object.create(q);
r.__proto__.__proto__.__proto__ === o;
Disclaimer: .__proto__ is deprecated. Don't use it in code. It has it's uses for debugging and sanity checks though.
The main point here is that accessing properties from o in r it has to walk 3 levels up the prototype chain and this gets expensive. To solve that problem, rather then cloning random objects you should clone specific blueprints (and you should have one blueprint per object).
// Parent blueprint
var Parent = (function _Parent() {
// create blank object
var self = Object.create({});
// object logic
return self;
}());
// factory function
var createParent = function _createParent(foo) {
// create a object with a Parent prototype
return Object.create(Parent, {
foo: { value: foo }
});
}
var Child = (function _Child() {
var self = Object.create(Parent);
// other stuff
return self;
}());
var createChild = function _createChild(bar) {
return Object.create(Child, {
bar: { value: bar }
})
};
Here's a snippet from some code I'm working on that you can use as an example:
var Sketchpad = (function _SketchPad() {
var self = Object.create({});
var mousemove = function _mousemove(e) {
this.drawLine(e);
};
self._init = function _init() {
this.$elem.bind({
"mousemove": mousemove.bind(this),
});
this.pens = {};
$("#clear").bind("click", this.clear.bind(this));
$("#undo").bind("click", (function _undoPath() {
this.pen.undo();
}).bind(this));
return this;
};
self.clear = function() {
this.paper.clear();
};
return self;
}());
createSketch = function _createSketchPad(id, w, h) {
var paper = Raphael(id, w, h);
var pen = createPen(paper);
var o = Object.create(Sketchpad, {
paper: { value: paper },
$elem: { value: $("#" + id) },
pen: {
get: function() { return pen; },
set: function(v) { pen = v; }
}
});
return o._init();
};
MooTools is one of the best libraries in terms of OOP Javascript.
You can create classes, interfaces, use inheritance, etc.
Documentation
http://mootools.net/docs/core
Tutorial - MooTools OOP
http://www.phpeveryday.com/articles/MooTools-Basic-Creating-Classes-MooTools-P919.html
You might also be interested in GNU ease.js. If you are not interested in the library itself, its manual goes extensively into the implementation details.
You could also see the author's paper on Classical OOP in ECMAScript.
You could try Joose, https://github.com/SamuraiJack/Task-Joose-NodeJS. Although, I'd personally recommend to stick with Javascript's object functionality as provided by ES5.
In the article you referenced, he was simply giving an example of what was possible with inheritance in javascript. He was not using a framework, but showing you how to extend your own classes you have written.
Frameworks for javascript include Backbone.js (mvc), and MooTools (oop).
extjs has support for OOP with Ext.define and Ext.extend (and Ext.ns). See this example on Sencha.com
Ext.extend is the older method, but is still sometimes useful. You would do something like this:
Ext.ns('myApp.myPackage'); // create a namespace
(function() { // this adds it to the namespace
var MyClass = Ext.extend(BaseClass, {
property: 1,
constructor: function(config) {
Ext.apply(this, config);
},
method: function(a, b) {
this.property = a + b;
}
});
myApp.myPackage.MyClass = MyClass;
}) ()
With Ext.define in Ext 4+ you can do:
Ext.define('myApp.myPackage.MyClass', // don't need to define the namespace first
extend: 'BaseClass' // notice the base class is referenced by a string,
requires: 'AnotherClass',
mixins: { mixin : 'MixinPackage' },
property: 1,
constructor: function(config) {
//...
}
method: function(a, b) {
this.property = a + b;
}
});
Note that you can also use traditional OOP in javascript with 'new' and function.prototype
If you want to do a real strong OOP in Javascript/Node, you can have a look at the full-stack open source framework Danf.
It allows you to use OOP (and so the same classes) on both the server (node) and client (browser) sides.
It also provides a nice dependency injection mechanism (looking as the one of Symfony2 if you come from the PHP community).
I want to migrate the javascript in my site from YU2 to YUI3, but I am only a poor amateur programer and I am stuck at the first pitfall.
I have the following code:
MyApp.Core = function() {
return {
init: function(e, MyAppConfig) {
if (MyAppConfig.tabpanels) {
MyApp.Core.prepareTabpanels(MyAppConfig.tabpanels);
}
},
prepareTabpanels: function(tabpanels) {
// Code here
}
}
}();
var MyAppConfig = {
"tabpanels":{"ids":["navigation"]}
};
YAHOO.util.Event.addListener(window, "load", MyApp.Core.init, MyAppConfig);
How can I pass the MyAppConfig object to the MyApp.Core.init function by using YUI3 "domready" event listener?
Thanks in advance!
You should be able to do something like:
var MyApp = {};
MyApp.Core = function(){ return {
init: function(MyAppConfig) {
console.log(MyAppConfig);
},
prepareTabpanels: function(tabpanels) {
// Code here
}
}
}();
var MyAppConfig = {
"tabpanels":{"ids":["navigation"]}
};
YUI().use('node', 'event', function(Y){
Y.on('domready', MyApp.Core.init, this, MyAppConfig);
});
Note that the event is not passed in as the first parameter, it is the config.
Y.on accepts parameters as <event_type>, <callback_function>, <context>, <params>..
any parameter after the third item is passed through to the callback function so MyAppConfig becomes the first parameter in your init.
EDIT
See the YUI3 API documentation here: http://developer.yahoo.com/yui/3/api/YUI.html#method_on