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How can I parse this JSON for use in Backbone View

I'm trying to learn Backbone and can't seem to match data from the fetch function into my Underscore template. How can can I get the children array in my JSON and match it to the template?
The Backbone.View looks like this:
var Projects = Backbone.Collection.extend({
url: '/tree/projects'
});
var Portfolio = Backbone.View.extend({
el: '.page',
render: function () {
var that = this;
var projects = new Projects();
projects.fetch({
success: function (projects) {
var template = _.template($('#projects-template').html());
that.$el.html(template({projects: projects.models}));
}
})
}
});
At the url: http://localhost:3000/portfolio/api/tree/projects
The JSON returned looks like this:
{
id:"projects",
url:"http://localhost:8888/portfolio/projects",
uid:"projects",
title:"Projects",
text:"",
files:[
],
children:[
{
id:"projects/example-1",
url:"http://localhost:8888/portfolio/projects/example-1",
uid:"example-1",
title:"Example 1",
images:"",
year:"2017",
tags:"Website",
files:[
],
children:[
]
},
{
id:"projects/example-2",
url:"http://localhost:8888/portfolio/projects/example-2",
uid:"example-2",
title:"Example #"2
text:"Example 2's text",
year:"2016",
tags:"Website",
files:[
{
url:"http://localhost:8888/portfolio/content/1-projects/4-example-2/example_ss.png",
name:"example_ss",
extension:"png",
size:244845,
niceSize:"239.11 kB",
mime:"image/png",
type:"image"
}
],
children:[
]
},
]
}
My Underscore file looks like this:
<script type="text/template" id="projects-template">
<h4>tester</h4>
<div>
<% _.each(projects.children, function (project) { %>
<div>
<div><%= project.get('year') %></div>
<div><%= project.get('title') %></div>
<div><%= project.get('tags') %></div>
</div>
<% }); %>
</div>
</script>

You can define a parse method on the collection:
var Projects = Backbone.Collection.extend({
url: '/tree/projects',
parse: function(response){
/* save other data from response directly to collection if needed.
for eg this.title = response.title; */
return response.children; // now models will be populated from children array
}
});

Do not use parse
While I usually agree with TJ, using parse on the collection is more like a hack than a definite solution. It would work only to get the children projects of a project and nothing more.
The parse function shouldn't have side-effects on the collection and with this approach, changing and saving fields on the parent project wouldn't be easily possible.
It also doesn't deal with the fact that it's a nested structure, it's not just a wrapped array.
This function works best when receiving wrapped data:
{
data: [{ /*...*/ }, { /*...*/ }]
}
Models and collections
What you have here are projects that have nested projects. A project should be a model. You also have files, so you should have a File model.
Take each resource and make a model and collection classes with it. But first, get the shared data out of the way.
var API_ROOT = 'http://localhost:8888/';
File
var FileModel = Backbone.Model.extend({
defaults: {
name: "",
extension: "png",
size: 0,
niceSize: "0 kB",
mime: "image/png",
type: "image"
}
});
var FileCollection = Backbone.Collection.extend({
model: FileModel
});
Project
var ProjectModel = Backbone.Model.extend({
defaults: function() {
return {
title: "",
text: "",
files: [],
children: []
};
},
getProjects: function() {
return this.get('children');
},
setProjects: function(projectArray, options) {
return this.set('children', projectArray, options);
},
getFiles: function() {
return this.get('files');
},
getSubProjectUrl: function() {
return this.get('url');
}
});
var ProjectCollection = Backbone.Collection.extend({
model: ProjectModel,
url: API_ROOT + '/tree/projects'
});
Project view
Then, make a view for a project. This is a simple example, see the additional information for tips on optimizing the rendering.
var ProjectView = Backbone.View.extend({
template: _.template($('#projects-template').html()),
initialize: function(options) {
this.options = _.extend({
depth: 0, // default option
}, options);
// Make a new collection instance with the array when necessary
this.collection = new ProjectCollection(this.model.getProjects(), {
url: this.model.getSubProjectUrl()
});
},
render: function() {
this.$el.html(this.template(this.model.toJSON()));
this.$projectList = this.$('.list');
// use the depth option to avoid rendering too much projects
if (this.depth > 0) this.collection.each(this.renderProject, this);
return this;
}
renderProject: function(model) {
this.$projectList.append(new ProjectView({
model: model,
depth: depth - 1
}).render().el);
}
});
With a template like this:
<script type="text/template" id="projects-template">
<h4><%= title %></h4>
<span><%= year %></span><span><%= tags %></span>
<p><%= text %></p>
<div class="list"></div>
</script>
Using the view:
var model = new ProjectModel({ id: "project" });
model.fetch({
success: function() {
var project = new ProjectView({
model: model,
depth: 2
});
}
});
Additional info
Nested models and collections
Efficiently rendering a list

Backbone Marionette - Log Model in Template

I am wondering how to log the model used in a Backbone.Marionette CompositeView's template?
The <% console.log(model) %> I am using causes an error Uncaught ReferenceError: model is not defined
Is there a way to log the content of the model from the template?
Here is a fiddle to my code: http://jsfiddle.net/16L1hen4/
Here is my Template and JavaScript
Template:
<div id="main"></div>
<script type="text/template" id="tree-template">
<li><%- name %></li>
<% //This console.log fails and I don't know why %>
<% console.log('inside template model =',model) %>
</script>
JavaScript:
var App = new Backbone.Marionette.Application();
App.addRegions({
mainRegion: '#main'
});
var TreeModel = Backbone.Model.extend({
});
var TreeCollection = Backbone.Collection.extend({
model: TreeModel,
url: 'https://api.mongolab.com/api/1/databases/backbone-tree/collections/tree?apiKey=akey'
});
// Tree branch view
var CompositeView = Backbone.Marionette.CompositeView.extend({
tagName: 'ul',
template: _.template( $('#tree-template').html() )
});
// Tree root view
var CollectionView = Backbone.Marionette.CollectionView.extend({
tagName: 'div',
className: 'js-tree-root',
childView: CompositeView,
});
var treeCollection = new TreeCollection();
treeCollection.fetch().done(function () {
var collectionView = new CollectionView({collection: treeCollection});
App.mainRegion.show(collectionView);
});
Edit: In a regular Backbone.View I can pass the model to the data as a property. Notice in this example that the View's model is passed to the template with a data property which can be logged in the template. This could be useful in the template to test for the existance of properties on the model. I am not sure how to do this using a Marionette CompositeView
var jsonData = {
"color": "red"
};
var TheModel = Backbone.Model.extend({
});
var TheView = Backbone.View.extend({
el: '#main',
tagName: 'ul',
template: _.template( $('#the-template').html() ),
render: function () {
var tmpl = this.template({data: this.model.toJSON()});
this.$el.html( tmpl );
}
});
var theModel = new TheModel(jsonData);
var theView = new TheView({model: theModel});
theView.render();
<div id="main"></div>
<script type="text/template" id="the-template">
<li><%- data.color %></li>
<% //Log the current model that the template uses %>
<% console.log('template model =',data) %>
</script>

This happens to be related to the anwser I posted on your question here : Backbone Marionette Composite View Rendering Template
and is cause by the same issue. model being undefined in the template context.
The data passed to your template is the following:
{_id: Object, name: "Level 1", children: Array[2]}
and model is undefined in this context.
If you want to log/control the data passed to your template you have should use SerializeData in such a way:
var CompositeView = Backbone.Marionette.CompositeView.extend({
tagName: 'ul',
serializeData: function(){
var data = Backbone.Marionette.CompositeView.prototype.serializeData.apply(this, arguments);
console.log(data);
return data;
},
template: _.template( $('#tree-template').html() )
});

underscore.js template || bind/append backbone

I asked question the other day on this app; after some good advice, I moved on and I now think this is a different issue.
Before, I was not getting any display on the screen/no errors or any console.logs. After working on it some more, I now have my model/view and some of my render function working.
I think the issue is with my template or with my append. Below is the full code as it stands now. There are //comments where I think there maybe some issues.
Any help with this would be greatly appreciated.
EDIT :: Thanks for the advice Niranjan. I made some the changes you mentioned; I took away the counter and sample data. With these new changes, my newsFeed.js is no longer being read and so I am unclear as to how to populate my collection. When I console.log out my collection I get an empty array with my defaults shown, but with the json file not being read in the first place how do I get anything to work?
EDIT#2 :: Thank you again Niranjan. With the changes you suggested and a few of my own, I now have the code below. The issue I have right now, Is my array is being populated far too many times. the JSON file has 8 entries in total and because of my _.each statement in my template it is looping 8 times where I only want it to loop once and then to split the array into separate entries. I tried first splitting it during my response parse but this didn't work, do you have any advice for this?
below the code is links to the live views of code and html/broswer content including a link to the JSON file.
My end goal is to click on one title and have the corresponding content show.
(function(){
var NewsFeedModel = Backbone.Model.extend({
defaults: {
title: '',
content: ''
}
});
var NewsFeedCollection = Backbone.Collection.extend({
model: NewsFeedModel,
url : 'newsFeed.js',
parse: function(response) {
console.log('collection and file loaded');
return response.responseData.feed.entries;
}
});
var NewsFeedView = Backbone.View.extend({
el : '.newsContainer ul',
template: _.template($("#feedTemp").html()),
initialize: function(){
var scopeThis = this;
_.bindAll(this, 'render');
this.collection.fetch({
success: function(collection){
scopeThis.render();
}
});
this.collection.bind( 'add', this.render, this);
console.log('View and Template read');
},
render: function () {
this.$el.html(this.template({
feed: this.collection.toJSON()
}));
console.log(this.collection.toJSON());
}
});
var newsFeedCollection = new NewsFeedCollection();
var newsFeedView = new NewsFeedView({
collection: newsFeedCollection
});
var title = newsFeedCollection.find('title');
var content = newsFeedCollection.find('content > title');
$(document).on("click", "#add", function(title, content) {
console.log("I have been clicked");
if($(title) == $(content)){
console.log('they match');
}
else{
console.log('they dont match');
}
$('.hide').slideToggle("slow");
});
}());
This is my underscore template.
<div class="span12">
<script id="feedTemp" type="text/template">
<% _.each(feed, function(data) { %>
<div id = "titleContent">
<%= data.title %>
<div id="content" class="hide">
<%= data.content %>
</div>
</div>
<% }); %>
</script>
</div>
I am using google drive as a testing ground; links for the full html/code.
https://docs.google.com/file/d/0B0mP2FImEQ6qa3hFTG1YUXpQQm8/edit [code View]
https://googledrive.com/host/0B0mP2FImEQ6qUnFrU3lGcEplb2s/feed.html [browser View]
https://docs.google.com/file/d/0B0mP2FImEQ6qbnBtYnVTWnpheGM/edit [JSON file]

There are lot more things in your code that can be improved.
Here is the JSFIDDLE.
Please go through the comments mentioned in the code.
For trying out things in Underscore's template, check Underscore's Template Editor.
Template:
<button id=add>Add</button>
<div class="newsConatiner">
<ul></ul>
</div>
<script id="feedTemp">
<% _.each(feed, function(data) { %>
<div id = "titleContent">
<h2> <%= data.title %> </h2>
<div id="content">
<%= data.content %>
</div>
</div>
<% }); %>
</script>
Code:
(function () {
var NewsFeedModel = Backbone.Model.extend({
//url: 'newsFeed.js',
defaults: {
title: '',
content: ''
}
});
var NewsFeedCollection = Backbone.Collection.extend({
model: NewsFeedModel,
url: 'newsFeed.js',
parse: function (response) {
console.log('collection and file loaded');
return response.responseData.feed.entries;
}
});
var NewsFeedView = Backbone.View.extend({
el: '.newsConatiner',
//template should not be inside initialize
template: _.template($("#feedTemp").html()),
initialize: function () {
_.bindAll(this, 'render');
this.render();
//ADD event on collection
this.collection.bind('add', this.render, this);
console.log('View and Template read');
},
/*
This initialize will fetch collection data from newsFeed.js.
initialize: function () {
var self = this;
_.bindAll(this, 'render');
this.collection.fetch({
success: function(collection){
self.render();
}
});
//ADD event on collection
this.collection.bind('add', this.render, this);
console.log('View and Template read');
},
*/
render: function () {
//This is how you can render
//Checkout how this.collection is used
this.$el.html(this.template({
feed: this.collection.toJSON()
}));
}
});
//Initialized collection with sample data
var newsCounter = 0;
var newsFeedCollection = new NewsFeedCollection([{
title: 'News '+newsCounter++,
content: 'Content'
}]);
//Created view instance and passed collection
//which is then used in render as this.collection
var newsFeedView = new NewsFeedView({
collection: newsFeedCollection
});
$('#add').click(function(){
newsFeedCollection.add(new NewsFeedModel({
title: 'News ' + newsCounter++,
content: 'Content'
}));
});
}());

BackboneJS - Display JSON data

How do I pass JSON data through a Backbone Model to a view?
my model looks like this:
define([
"jquery",
"backbone"
],
function($, Backbone) {
var Model = Backbone.Model.extend({
url: "./bands.php",
defaults: {
"id": '',
"band": '',
"label": ''
}
});
return Model;
});
my View code looks like:
define(['backbone','handlebars', 'text!templates/bandpage.html'],
function(Backbone,Handlebars, Template) {
'use strict';
var BandpageView = Backbone.View.extend({
template: Handlebars.compile(Template),
initialize: function () {
},
render: function() {
this.$el.html(this.template(this.model.toJSON()));
return this;
}
});
return BandpageView;
}
);
and in my HTML template I have
<div>
<p><%= id %></p>
<p><%= band %></p>
<p><%= label %></p>
</div>
It doesnt show anything and I get the error "Cannot call method 'toJSON' of undefined"
what am I doing wrong?

Try this:
Update View initialize as:
initialize: function () {
this.listenTo(this.model, "change", this.render);
},
Create view instance as :
var view = new BandpageView({model: new Model()});

Backbone JS populating model/collection correctly

I have a collection which contains one model. In my template I should be able to do:
<% _.each(collection, function(model) { %>
<p>logged in <%= model.username %>!</p>
<% }); %>
But I've found I need to do:
<% _.each(models, function(model) { %>
<p>logged in <%= model.attributes.username %>!</p>
<% }); %>
I'm not sure exactly what the problem is but the model isn't being populated properly. Anyone know why this is happening and how I can set the values within the model so I can loop over a collection of models and access the values simply with model.username ?
Thank you in advance.
Here's my model and collection:
var AccountModel = Backbone.Model.extend({
defaults:
{
username: "bob"
}
});
var AccountCollection = Backbone.Collection.extend(
{
model: AccountModel,
url: "/php/account-details.php",
parse: function(data, xhr)
{
return data
},
initialize: function()
{
}
});
Here's my fetch function:
fetchAccountCollection: function(){
var $this = this;
$this.homepageAccountCollection = new AccountCollection();
$this.homepageAccountCollection.fetch(
{
dataType: "json",
cache: false,
success: function(collection)
{
Backbone.trigger('accountcollection:loaded', collection);
},
error: function()
{
console.log("fetchAccountCollection: error");
}
});
},
When the success function is called the trigger invokes the render function within the controller:
renderAccount: function(collection)
{
var $this = this;
$this.loginPageView = new LoginView(
{
el: '#login-form',
template: 'loggedin-template',
collection: collection
});
$this.loginPageView.render();
},
When $this.loginPageView.render(); is called the following code is executed:
render: function()
{
var collection = this.options.collection;
var tpl = _.template($(this.options.template).html(), collection);
this.$el.html(tpl);
return this;
},
The value of the username is being returned from a PHP script like so:
$array=array('username' => $user['username']);
echo json_encode($array);

Underscore's each method (and many others) are mixed directly into the collection. Use collection.each(function () { ... }) instead of _.each(collection ...).

The problem is that your passing a Backbone.Collection to your template, so when you end up calling the following in your template:
_.each(models,function(model) { ... });
You are iterating through collection.models array which is an array of Backbone.Model's. Since a Backbone.Model stores model values within the attributes property, you have to access via model.attributes.username, you could also use model.get('username'), which would work as well.
As you stated, you would like to access via model.username, and you can do that by calling collection.toJSON() before passing it to the template, you have to put it in an object such as, {collection:collection.toJSON()};. Check out the documentation for toJSON. The method exists for both Backbone.Collection and a Backbone.Model.
The code would be the following:
render: function() {
var collection = this.options.collection;
var tpl = _.template($(this.options.template).html(), {collection:collection.toJSON());
this.$el.html(tpl);
return this;
}
Then you could use your template like:
<% _.each(collection, function(model) { %>
<p>logged in <%= model.username %>!</p>
<% }); %>
Here is a minimal JSBIN DEMO.
As a side note: It looks like your using a version of backbone < 1.1.0. Just be aware this.options goes away in the newer versions. When you upgrade be sure to have a look at the Change Log.