Backbone Start twice - backbone.js

I started a simple Backbone app, but my start function run twice. What did I wrong?
var ActivityApp = new (Backbone.View.extend({
Models: {},
Views: {},
Collections: {},
start: function() {
console.log('ad');
} }))({el: document.body});
$(function(){ ActivityApp.start(); })

The code you provided works fine.. http://jsfiddle.net/ferahl/5zzzchpq/
You wrote it in a strange way though, this makes more sense and is the "backbone way":
var ActivityApp = Backbone.View.extend({
initialize: function() {
console.log('initialize');
}
});
new ActivityApp({
el: document.body
});

Related

edit - backbone.js beginner attempting to load data

Attempting to post a beginner question but not making it past the "quality standards" filter.
I read through the thread on the error message. Are beginner questions too basic? Understandable but it might be better to put that in the error message. I include my code and my English is correct outside of the code block. The question has not been addressed, or at least is not returned from various search patterns. Is there anyway to appeal the filter as multiple rewrites have not cleared the hurdle or solved my, admittedly beginner, problem? In a last ditch attempt to hack the filter I'm pasting my original question in bellow with a few English only edits. edit - this seems to have worked but leaving above paragraph in to not jinx it.
Trying to load data into backbone but the render function is not firing.
Firebug shows the GET is arriving with the correct data string.
I have attempted to assign "this" to a variable and fire as a function but still no luck.
(function($) {
var DObj = Backbone.Model.extend({
defaults: {
dstring: 'dstring again'
},
});
var MObs = Backbone.Collection.extend({
defaults: {
model: DObj
},
model: DObj,
url: 'scr/bbone.php'
});
var MView = Backbone.View.extend({
initialize: function() {
this.collection = new MObs();
//this.collection.bind("reset", this.render, this);
this.collection.on("sync", this.render, this);
//this.collection.bind("change", this.render, this);
this.collection.fetch();
},
render: function() {
alert("here : ");
}
});
var newMob = new MView();
})(jQuery);
I have rewritten the code with mockjax to mock response from the server, here it is:
<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.9.1/jquery.min.js"></script>
<script src="http://cdnjs.cloudflare.com/ajax/libs/underscore.js/1.4.4/underscore-min.js"></script>
<script src="http://cdnjs.cloudflare.com/ajax/libs/backbone.js/1.0.0/backbone-min.js"></script>
<script src="http://cdnjs.cloudflare.com/ajax/libs/jquery-mockjax/1.5.1/jquery.mockjax.min.js"></script>
<script>
var DObj = Backbone.Model.extend({
});
var MObs = Backbone.Collection.extend({
model: DObj,
url: '/movies'
});
$.mockjax({
type: 'GET',
url: '/movies',
contentType: 'text/json',
status: 200,
response: function() {
this.responseText = JSON.stringify(new MObs([{ name: 'Lincoln' }, { name: 'Argo' }]));
}
});
var MView = Backbone.View.extend({
initialize: function() {
this.collection.on("sync", this.render, this);
},
render: function() {
alert("here : ");
}
});
(function($) {
var newCol = new MObs();
newMob = new MView({ collection: newCol });
newCol.fetch({
success: function () { console.log('Success'); },
error: function() { console.log('Error'); }
});
})(jQuery);
I think there are many issues with code, the issue you were specifically asking for has to do with the server response; you should see an alert with the above code. I recommend you read backbone.js documentation for others.

How to pass a template to a view in Backbone

I'm trying to pass a template to my view. I have several different templates I want to use and want to be able to switch them up in my router. I get no errors, but I get no results. It looks like the initialize method isn't being called in my second view. Here is my code:
(function() {
window.App = {
Models: {},
Collections: {},
Views: {},
Router: {}
};
window.template = function(id) {
return _.template( $('#' + id).html() );
};
var vent = _.extend({}, Backbone.Events);
_.templateSettings.interpolate = /\[\[(.+?)\]\]/g;
App.Router = Backbone.Router.extend({
routes: {
'' : 'index',
'send-message' : 'sendMessage',
'*other' : 'other'
},
index: function() {
t = new (App.Collections.Tables.extend({ url: 'main-contact'}))();
tables = new (App.Views.Tables.extend({
collection: t, template: template('mainContactTemplate')}))();
$('#web-leads').html(tables.el);
},
sendMessage: function() {
t = new (App.Collections.Tables.extend({ url: 'send-message'}))();
tables = new App.Views.Tables.extend({
collection: t, template: template('sendMessageTemplate')});
$('#web-leads').html(tables.el);
},
other: function() {
}
});
// Main Contact
App.Models.Table = Backbone.Model.extend({});
App.Collections.Tables = Backbone.Collection.extend({
model: App.Models.Table,
initialize: function(models, options) {
this.fetch({
success: function(data) {
//console.log(data.models);
}
});
if (options) {
this.url = this.url || options.url;
}
}
});
App.Views.Tables = Backbone.View.extend({
tagName: 'ul',
initialize: function() {
this.collection.on('reset', this.render, this);
},
render: function() {
return this.collection.each(this.addOne, this);
},
addOne: function(model) {
var t = new App.Views.Table({ model: model, template: template});
this.$el.append(t.render().el);
return this;
}
});
App.Views.Table = Backbone.View.extend({
tagName: 'li',
template: this.template,
initialize: function (attrs) {
this.options = attrs;
console.log(this.options);
},
render: function() {
this.$el.html(this.template(this.model.toJSON()));
return this;
}
});
new App.Router();
Backbone.history.start();
})();
EDIT: I was missing some parenthesis. But now I get an error of an unrecognized expression. Initialize is now being called.
The way you are doing it in App.Views.Table is (as far as I can tell) the "standard" way of using templates with Backbone. There are of course several alternatives though, and none of them are "wrong" per say.
That being said, you do have a couple problems in your code. Let's start with:
template: this.template,
At the time that code runs you're not in an instance of App.Views.Tables, you're in the global space declaring a class that (later) will be used to make instances. At that moment though, this just refers to window. What you really want to do is set the template in your initialize, which leads me to:
initialize: function(options) {
this.template = options.template;
},
But then there's one last problem:
var t = new App.Views.Table({ model: model, template: template});
there is no template variable in that function, so you're really doing template: undefined. That should use a real template.
All that being said, you might want to just consider putting the template on the view directly, the way you sort of tried to:
template: Handlebars.compile('<span>{{test}}</span>'),
After all, any given view should always use the same template, right? Also, you might want to consider moving the:
render: function() {
this.$el.html(this.template(this.model.toJSON()));
return this;
}
in to a parent class, so that you can share it between all of your templated views, instead of having to repeat it.

Super simple-minimal Backbone script requested

Looking for the absolute minimum script to get Backbone working. Tried piecing various tutorials and sample together, but having problems getting views to work. Nothing fancy, I'll take raw json in the browser right now. Just a basic skeleton to help connect the dots and build on. I've tried various variations on the following:
(function ($) {
var model = Backbone.Model.extend({
idAttribute: 'custId'
});
var collection = Backbone.Collection.extend({
initialize: function(){
},
model: model,
url: '/cust'
});
var view = Backbone.View.extend({
initialize: function(){
_.bindAll(this, 'render'); // fixes loss of context for 'this' within methods
this.collection.bind("reset", this.render);
this.render();
},
el: $('#content'),
template: Handlebars.compile($("#contentTemplate").html()),
render: function(){
$(this.el).html( this.template(this.model.toJSON()));
},
tagName: "li"
});
var router = Backbone.Router.extend({
initialize: function(){
var newCollection = new collection;
newCollection.fetch();
},
route: {
"": "home"
},
home: function(){
this.view = new view({collection: newCollection});
$('#content').html(this.view.el);
}
});
var app = new router();
}(jQuery))
Thanx.
You are misusing the el attribute. $('#content').html(this.view.el) will result in copying the $('#content') element inside itself (because view.el is equal to $('#content')).
You should try removing the el attribute from the view object and let it generate itself. Then $('#content').html(this.view.el); should work.
One other possible problem is that you are rendering the entire collection inside a li element - was this what you are going for? The best way to go about this would be to have each model in the collection represent a li tag and the collection a ul tag.
Other issues:
the view element is receiving a collection but you are trying to render a model
in the router, newCollection is not accessible in the home method
You are not calling Backbone.history.start()
Here is how i would rewrite the code:
var model = Backbone.Model.extend({
idAttribute: 'custId'
});
var model_view = Backbone.View.extend({
template: Handlebars.compile($("#modelTemplate").html()),
tagName: 'li',
initialize: function() {
_.bindAll(this, 'render');
this.render();
this.on('change',this.render);
},
render: function() {
$(this.el).html( this.template(this.model.toJSON()) );
return this;
}
});
var collection = Backbone.Collection.extend({
initialize: function(){
},
model: model,
url: '/cust'
});
var collection_view = Backbone.View.extend({
tagName: "ul",
initialize: function(){
_.bindAll(this, 'render','renderModels');
this.render();
this.renderModels();
this.collection.bind("reset", this.render);
this.collection.bind("reset", this.renderModels);
},
render: function(){
// just create the 'ul' tag; we will populate it with model view elements; a collection template is no longer needed
return this;
},
renderModels: function() {
this.collection.each(function(obj){
var view = new model_view({
model: obj
});
$(this.el).append(view.el);
},this);
}
});
var router = Backbone.Router.extend({
initialize: function(){
this.newCollection = new collection();
this.newCollection.fetch();
},
route: {
"": "home"
},
home: function(){
this.view = new collection_view({collection: this.newCollection});
$('#content').html(this.view.el); // #content should not be a 'ul' tag, the 'ul' is generated by the collection_view
}
});
var app = new router();
Backbone.history.start();
Make sure you update your templates accordingly.
Please excuse possible errors, i had no means to test the code but i believe it points out the logic you should use.
Cheers!

Backbone/Underscore uniqueId() Odd Numbers

I'm relatively new to Backbone and Underscore and have one of those questions that's not really an issue - just bugging me out of curiosity.
I built a very simple app that allows you to add and remove models within a collection and renders them in the browser. It also has the ability to console.log the collection (so I can see my collection).
Here's the weird thing: the ID's being generated are 1,3,5... and so on. Is there a reason specific to my code, or something to do with BB/US?
Here's a working Fiddle: http://jsfiddle.net/ptagp/
And the code:
App = (function(){
var AppModel = Backbone.Model.extend({
defaults: {
id: null,
item: null
}
});
var AppCollection = Backbone.Collection.extend({
model: AppModel
});
var AppView = Backbone.View.extend({
el: $('#app'),
newfield: $('#new-item'),
initialize: function(){
this.el = $(this.el);
},
events: {
'click #add-new': 'addItem',
'click .remove-item': 'removeItem',
'click #print-collection': 'printCollection'
},
template: $('#item-template').html(),
render: function(model){
var templ = _.template(this.template);
this.el.append(templ({
id: model.get('id'),
item: model.get('item')
}));
},
addItem: function(){
var NewModel = new AppModel({
id: _.uniqueId(),
item: this.newfield.val()
});
this.collection.add(NewModel);
this.render(NewModel);
},
removeItem: function(e){
var id = this.$(e.currentTarget).parent('div').data('id');
var model = this.collection.get(id);
this.collection.remove(model);
$(e.target).parent('div').remove();
},
printCollection: function(){
this.collection.each(function(model){
console.log(model.get('id')+': '+model.get('item'));
});
}
});
return {
start: function(){
new AppView({
collection: new AppCollection()
});
}
};
});
$(function(){ new App().start(); });
if you look in the backbone.js source code you'll notice that _.uniqueId is used to set a model's cid:
https://github.com/documentcloud/backbone/blob/master/backbone.js#L194
that means that every time you create a model instance, _.uniqueId() is invoked.
that's what causing it to increment twice.

Backbone.js basics: creating a view

I'm just starting to learn backbone.js. I'm following this tutorial here at backbonetutorials.com, but for some reason I'm not being able to put it working. Here's what I've got so far (fiddle):
var View = Backbone.View.extend({
el: $('.container'),
initialize: function() {
this.render();
},
render: function() {
var templ = _.template($('#template').html(), {});
this.el.html(templ);
},
events: {
"click button": "buttonClick"
},
buttonClick: function() {
alert('clicked!');
}
});
var view = new View();​
What's wrong with the above? I've almost just copy/pasted from the tutorial to the fiddle. Is it related to the backbone/underscore versions being used?
Thanks in advance.
try
this.$el.html(templ);
instead of
this.el.html(templ);
http://jsfiddle.net/eykKL/4/

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