i am a newbie to web application development. i have a backbone model named LoginModel. I want to create an object of it and make it globally accessible from any Backbone View which will be loaded dynamically. Here is my model..
define(['underscore', 'backbone'], function(_, Backbone) {
LoginModel = Backbone.Model.extend({
initialize: function(){ },
defaults:{
userName: 'undefined',
userID: 'undefined'
},
urlRoot: 'https://xxxx.xx.xxxxxx',
parse: function(response, options){
return{
userName: response.userName,
userId:response.userId
};
}
});
});
You could pin the newly created object to an already existing global object that you're using, such as Backbone :
Backbone.Model.definitions = {
loginModel : Backbone.Model.extend({...})
}
and the use it as this :
new View({model : Backbone.Model.definitions.loignModel});
It may not be the shortest way, but it's cleaner than polluting the global namespace with different variables.
Rather than attaching to the Backbone.Model prototype or to the global window scope, I find it effective to attach it to a separate app object (provided by backbone-boilerplate and most other implementations).
You app object then can be required into any other module that requires access to the current user context.
app/app.js
define(function(require, exports, module) {
"use strict";
var app = module.exports;
// Initialize configuration and context objects
app.root = "/";
app.currentUser = null; //will be initialized in app/main.js
});
app/main.js
require(["config"], function() {
require(["app", "LoginModel", "router"], function(app, models, Router) {
app.currentUser = new LoginModel();
app.currentUser.fetch();
app.router = new Router();
})
});
Just create a global instance of the model, for example
var globalLoginModel = new LoginModel();
or
window.globalLoginModel = new LoginModel();
Then just pass it into any view that you want to use it in, for example
new View1({ model : globalLoginModel });
new View2({ model : globalLoginModel });
new View3({ model : globalLoginModel });
That should be it.
D
Related
I am learning Backbone.js and as a trial project I am creating a little WordPress user management application. So far my code shows a listing of all WordPress users and it has a form which enables you to add new users to the application.
This all works fine however when you add a new user the listing of users doesn't update automatically, you need to refresh the page to see the new user added which isn't ideal and defeats one of the benefits of Backbone.js!
I have a model for a user and then a collection which compiles all the users. I have a view which outputs the users into a ul and I have a view which renders the form. How do I make my code work so when the .save method is called the view which contains the users updates with the new user? Or is there another way to approach this?
//define the model which sets the defaults for each user
var UserModel = Backbone.Model.extend({
defaults: {
"username": "",
"first_name": "",
"last_name": "",
"email": "",
"password": "",
},
initialize: function(){
},
urlRoot: 'http://localhost/development/wp-json/wp/v2/users'
});
//define the base URL for ajax calls
var baseURL = 'http://localhost/development/wp-json/wp/v2/';
//function to define username and password
function authenticationDetails(){
var user = "myUserName";
var pass = "myPassword";
var token = btoa(user+':'+pass);
return 'Basic ' + token;
}
//add basic authorisation header to all API requests
Backbone.$.ajaxSetup({
headers: {'Authorization':authenticationDetails()}
});
//create a collection which returns the data
var UsersCollection = Backbone.Collection.extend(
{
model: UserModel,
// Url to request when fetch() is called
url: baseURL + 'users?context=edit',
parse: function(response) {
return response;
},
initialize: function(){
}
});
// Define the View
UserView = Backbone.View.extend({
model: UserModel,
initialize: function() {
// create a collection
this.collection = new UsersCollection;
// Fetch the collection and call render() method
var that = this;
this.collection.fetch({
success: function () {
that.render();
}
});
},
// Use an external template
template: _.template($('#UserTemplate').html()),
render: function() {
// Fill the html with the template and the collection
$(this.el).html(this.template({ users: this.collection.toJSON() }));
return this;
},
});
var userListing = new UserView({
// define the el where the view will render
el: $('#user-listing')
});
NewUserFormView = Backbone.View.extend({
initialize: function() {
this.render();
},
// Use an external template
template: _.template($('#NewUserTemplate').html()),
render: function() {
// Fill the html with the template and the collection
$(this.el).html(this.template());
return this;
},
events: {
'click .create-user':'addNewUser'
},
addNewUser: function(){
var newFirstName = $('.first-name').val();
var newLastName = $('.last-name').val();
var newEmail = $('.email').val();
var newPassword = $('.password').val();
var newUserName = newFirstName.toLowerCase();
var myNewUser = new UserModel({username:newUserName,first_name:newFirstName,last_name:newLastName,email:newEmail,password:newPassword});
console.log(myNewUser);
myNewUser.save({}, {
success: function (model, respose, options) {
console.log("The model has been saved to the server");
},
error: function (model, xhr, options) {
console.log("Something went wrong while saving the model");
}
});
}
});
var userForm = new NewUserFormView({
// define the el where the view will render
el: $('#new-user-form')
});
All backbone objects (models, collections, views) throw events, some of which would be relevant to what you want. Models throw change events when their .set methods are used, and Collections throw add or update events... a complete list is here.
Once you know which events are already being thrown, you can listen to them and react. For example, use listenTo - in your view's initialize, you can add:
this.listenTo(this.collection, 'add', this.render);
That will cause your view to rerender whenever a model is added to your collection. You can also cause models, collections, whatever, to throw custom events using trigger from anywhere in the code.
EDIT: For the specific case of getting your user listing view to rerender when a new user is added using the form, here are the steps you can take... In the initialize method of your UserView, after the initialize the collection, add:
this.listenTo(this.collection, 'add', this.render);
Then in your form view... assuming you want to wait until the save is complete on your server, in the addNewUser method, in the success callback of your save, add:
userlisting.collection.add(model);
This will work, since the instance of your UserView is in the global scope. Hope this one works for you!
i'm trying to connect model and collection using parse.com but i'm confused. I'm tring to fetch by collection using backbone and javascript api parse.com but compare this error:POST https://api.parse.com/1/classes 404 (Not Found).
Model:
var Person = Backbone.Model.extend({
defaults:{
},
initialize:function(){
console.log("inperson");
this.validate();
this.send();
},
validate:function(){
console.log("validate");
},
send:function(){
var user = new Parse.User();
user.set("username", this.get("username"));
user.set("password", this.get("password"));
user.set("email", this.get("email"));
user.signUp(null, {
success: function(user) {
// Hooray! Let them use the app now.
},
error: function(user, error) {
// Show the error message somewhere and let the user try again.
alert("Error: " + error.code + " " + error.message);
}
});
}
});
return Person;
});
Collection:
var Usercollection = Parse.Collection.extend({
model:Person,
initialize:function(){
}
});
return Usercollection;
});
and finally the view that call the colletion and fetch:
var HomeView = Backbone.View.extend({
template: Handlebars.compile(template),
events: {
},
initialize: function() {
console.log("inhomeview");
var amici = new Usercollection();
amici.fetch({
success: function(collection) {
amici.each(function(object) {
console.warn(object);
});
},
error: function(amici, error) {
// The collection could not be retrieved.
}
});
},
render: function() {
}
});
return HomeView;
});
Cant you just swap the backbone collection and model to Parse's ones? (You only used the Parse type of the collection, not the model!)
Try switch that Backbone model to a Parse.Object .
Step by step below:
First of all Lets create a new app on Parse.com, mine is called FunkyAppartments.
Insert the script tag for loading Parse javascript lib into index.html or whathever:
<script src="http://www.parsecdn.com/js/parse-1.5.0.min.js"></script>
Switch the backbone model and collection to use parse types instead (and rename the fetch method if you have extended backbones, since we do not want to overide the one of parse):
//var Appartment = Backbone.Model.extend(); Backbone wo. Parse.com
var Appartment = Parse.Object.extend("Appartment");
//var Appartments = Backbone.Collection.extend({ Backbone wo. Parse.com
var Appartments = Parse.Collection.extend({
model: Appartment,
loadAppartments: function(callback){
debugger;
this.query = new Parse.Query(Appartment);
this.fetch();
}
});
I added a debugger tag in the load appartments so that developer tools breaks in the middle of the controller, here I have access to the Appartment private type of the controller, hence i can store some data on the parse server and verify by pasting the below in the developer tools console.
var testAppartment = new Appartment();
testAppartment.save({name: "foobars"}).then(function(object) {
alert("yay! it worked");
});
Yei, the data shows up in the parse.com UI for the app we just added there. And more importantly it shows up in our frontend. That was easy!
UPDATE: PROBLEMS W BACKBONE 1.2.1, MARIONETTE 2.4.2, UNDERSCORE 1.8.3
I noticed that I actually had been using old versions of marionette, backbone and underscore.js. An initial update appeared to break the application.
After some research i found that it was the parse part that did not return objects that would successfully render. Hence I changed the collection type back to an extension of: Backbone.collection instead of Parse.collection.
I also had to override the query method, since the objects would not save on the correct id, updating an object resulted in a new object being added instead of an old one being updated.
var Apartment = Parse.Object.extend('Appartment');
var Apartments = Backbone.Collection.extend({
model: Apartment,
query: new Parse.Query(Apartment),
initialize: function(){
MyApp.vent.on('search:param', function(param){self.search(param); });
var self = this;
this.query.find({
success: function(results){
self.reset();
results.forEach(function(result){
result.attributes.id__ = result.id
var ap = new Apartment(result.attributes);
self.add(ap);
});
}
});
}
});
I added an attribute: id__ to hold the parse id (naming it just id did not work since it backbone interfered with it, making it disappear).
Finally in saving the model to parse i utilized id__ as id in the save call:
var ApartmentEditView = Backbone.Marionette.ItemView.extend({
template: "#apartment-edit-template",
className: "apartmentDetail",
events: {
"click .store": "storeEdit",
"click .close": "closeEdit"
},
storeEdit: function(){
var priceNum = Number($('#price_field').val().replace(/\s/g, ''));
this.model.set({
id: this.model.attributes.id__,
name:$('#name_field').val(),
price:priceNum,
description:$('#desc_field').val(),
url:$('#url_field').val()
});
this.model.save();
this.closeEdit();
},
closeEdit: function(){
var detailView = new ApartmentDetailView({model: this.model});
MyApp.Subletting.layout.details.show(detailView);
}
});
Now the object is updated correctly in the database.
I have a Backbone app that is working properly, however, when I tried to reorganize the code under a namespace I can't get it to do anything. I can't even trigger events (by clicking on ids) for views that I know are getting initialized (through console log messages), so I'm wondering if I've introduced some fundamental flaw somehow. I'm following a pattern set out by this blog (in french) http://www.atinux.fr/2011/12/10/organiser-son-code-backbone-js-en-modules/
In the main application.js (see below), I instantiate all of the views and models after initiating the app on document ready. One change introduced as a result of creating this namespace was setting the models for the views with this.models.game
this.views.clock_view = new this.Views.clockView({ model: this.models.game});
Inside the modules folder, I had a views.js and a models.js. I created each view and object like this, prefaced with app.Views or app.Models accordingly
app.Views.announceView = Backbone.View.extend({
....
app.Views.optionsView = Backbone.View.extend({
...
This app.Views.optionsView is getting initialized (according to a console.log statement in the initializer) but when I click on #new_game, the console.log in the startNewGame is not getting triggered
'click #new_game': 'startNewGame'
// 'click .action_button': 'startNewGame'
},
startNewGame: function() {
console.log("startNewGame");
this.model.new();
},
As a result of the namespacing, one other key change I made was when I created new views inside one of the other views. Under the previous (non-namespaced app), I created individual question items from a QuestionListView
var view = new QuestionListItemView({ model: game });
but now I'm doing
var view = new app.Views.questionListItemView({ model: app.models.game })
because the instance of the model was saved to this.models.game in application.js, however, I also tried using 'this.models.game'
var view = new app.Views.questionListItemView({ model: this.models.game })
Either way, before the games model gets involved, I can't trigger the startNewGame function outlined above, so it's not solely an issue of how to identify the model.
I also wondered whether i should be using this.Views or app.Views after the 'new' when creating new views from within
var view = new app.Views.questionListItemView({ model: this.models.game })
I'd be grateful if you could help me identify any flaws I've introduced.
application.js
var app = {
// Classes
Collections: {},
Models: {},
Views: {},
// Instances
collections: {},
models: {},
views: {},
init: function () {
this.models.game = new this.Models.game();
this.views.story_view = new this.Views.storyView(); #doesn't have a model
this.views.clock_view = new this.Views.clockView({ model: this.models.game});
this.views.field_view = new this.Views.fieldView({ model: this.models.game});
this.views.options_view = new this.Views.optionsView({ model : this.models.game});
this.views.announcement_view = new this.Views.announceView({ model: this.models.game});
this.views.question_list_view = new this.Views.questionListView({ model : this.models.game});
this.views.question_list_item_view = new this.Views.questionListItemView({ model : this.models.game});
}
};
$(document).ready(function () {
app.init();
}) ;
The options view is getting initialized but I can't trigger the startNewGame function when I click that #id
app.Views.optionsView = Backbone.View.extend({
// el: $("#options"),
el: $("#options"),
initialize: function() {
console.log("app views OptionsView initialized");
// this.model.bind("gameStartedEvent", this.removeGetAnswerButton, this);
this.model.bind("gameStartedEvent", this.disableNewGame, this);
},
events: {
'click #demo': 'startDemo',
'click #new_game': 'startNewGame'
// 'click .action_button': 'startNewGame'
},
startDemo: function(){
console.log("start demo");
this.model.demo();
},
startNewGame: function() {
console.log("startNewGame");
this.model.new();
},
disableNewGame: function(){
$('#new_game').attr("disabled", true);
}
});
Update
My file structure looks like this
<%= javascript_include_tag 'application.js'%>
<%= javascript_include_tag 'modules/models'%>
<%= javascript_include_tag 'modules/views'%>
At the top of the views and models file, I just do something like this
app.Views.optionsView = Backbone.View.extend({
ie.. there is no further document ready. In fact, including another document ready in these files breaks the application.js init
Prior to using the namespace, I defined the element this way in the view
el: $("#options")
which, as was pointed out in the comments to this question, is not the ideal way to do it(see #muistooshort comment below), (even though it worked).
Defining the el this way instead
el: '#options'
got it working, and let Backbone "convert it to a node object" on its own.
i am new to backbone.js and need a little help sending data to a template. Im using a model with fetch, and a collection. here is the code :
(function($) {
var UserModel = Backbone.Model.extend({
urlRoot : '/users',
defaults : {
name : '',
email : ''
},
initialize : function() {
_.bindAll(this);
this.fetch();
},
parse : function(res) {
return JSON.stringify(res);
},
});
var users_coll = Backbone.Collection.extend({
//model: UserModel
initialize : function() {
var u = new UserModel();
this.model = u;
}
});
var displayView = Backbone.View.extend({
initialize : function() {
this.collection = new users_coll();
//_.each(this.collection.models, alert);
//console.log(this.collection);
//alert(JSON.stringify(this.collection.models));
this.render();
},
render : function() {
var tmpl = _.template($("#data-display-tpl").html());
this.$el.html(tmpl);
}
});
var view = new displayView({
el : $("#data-display")
});
})(jQuery);
it's working fine upto the model part. In the parse function of the model, i have used console.log() and everything seems fine. i get a properly formated json, and the fetch works fine too.
however in my collection i get nothing when i try console.log(user_coll.models).
i think i am probably missing something really small. not sure what, maybe the flow of things is all wrong.
I tried to modify your code just a bit to get poin trough...hope it helps clarify few basics.
I also didn't try provided example, but in theory it should work ;)
Here is how his example should be done...
Let's imagine Twitter app for example. Twitter app has only one model that represents one user in system. That's UserModel
var UserModel = Backbone.Model.extend({
urlRoot : '/user', // this is just for modifying one specific user
defaults : {
name : '',
email : ''
},
initialize : function() {
_.bindAll(this);
//this.fetch(); // WRONG: This call was "wrong" here
// fetch() should be done on Collection not model
},
parse : function(res) {
return JSON.stringify(res);
},
});
Now, you can have many lists of users on Twitter right. So you have two lists. In one list you have Friends users, and in other Family users
var UsersFriendsCollection = Backbone.Collection.extend({
model: UserModel // you tell Collection what type ob models it contains
url: '/users/friends',
initialize : function() {
// jabadaba whatever you need here
}
});
var UsersFamilyCollection = Backbone.Collection.extend({
model: UserModel // you tell Collection what type ob models it contains
url: '/users/family',
initialize : function() {
// jabadaba whatever you need here
}
});
...
var displayView = Backbone.View.extend({
initialize : function() {
this.collection = new UsersFriendsCollection();
this.collection.fetch(); // so you call fetch() on Collection, not Model
console.log(this.collection); // this should be populated now
//_.each(this.collection.models, alert);
//alert(JSON.stringify(this.collection.models));
this.render();
},
render : function() {
// collection data is avail. in templating engine for iteration now
var tmpl = _.template($( "#data-display-tpl" ).html(), this.collection);
this.$el.html(tmpl);
}
});
A collection's model attribute is meant for specifying what type of model the collection will contain and if specified you can pass the collection an array of raw objects and it will add and create them. From the docs
Override this property to specify the model class that the collection
contains. If defined, you can pass raw attributes objects (and arrays)
to add, create, and reset, and the attributes will be converted into a
model of the proper type
So when in your code you have
var u = new UserModel();
this.model = u;
You aren't actually adding the model to the collection. Instead you can use the collections add or fetch methods.
i try to fetch a record of a rails-api (same host) into my backbone collection. i have the following code:
// Models
App.GeeksModel = Backbone.Model.extend({
urlRoot: "/geeks",
idAttribute: "id"
});
// Collections
App.GeeksCollection = Backbone.Collection.extend({
url: "/geeks",
model: App.GeeksModel
});
in my router i have the following
// Router
App.GeekRouter = Backbone.Router.extend({
routes: {
"": "index"
},
initialize: function() {
console.log("router - init");
},
index: function() {
console.log("route - index");
var geekCollection = new App.GeeksCollection();
var mapView = new App.GeeksMapView({ el: $("#foo"), model: geekCollection });
geekCollection.fetch();
}
});
when browsing the url, the view loads correctly and at the server i see, that one entry is fetched from the database. but as soon as i check the model length in my view using
this.model.length
the collection is empty... any advice on this?
thanks
EDIT 1:
when changing the index router method to
var mapView = new App.GeeksMapView({ el: $("#map"), collection: geekCollection });
and e.g. check for the collection length in the views intialize method
...
initialize: function() {
this.render();
console.log(this.collection.length);
},
...
it retunes 0 as well... so nothing changed!
I believe you want to do collection.length or if accessing from the model - each model holds reference to collection in which it was created model.collection.length - if this is referencing to collection doing just this.length should be enough, if it's a model then this.collection.length will do it for you.
Models have no property length so should always be undefined unless you define it yourself.