Backbone Views as CommonJS modules - backbone.js

I'm trying to get my head around using CommonJS modules within a Backbone application, so I have a skeleton Backbone View defined in /views/categories/edit.js:
app.Views.quoteCategoriesEdit = app.Ui.ModalView.extend({
className: '',
template: JST["templates/quotes/categories/quote-categories-edit.html"],
events: {
'click [data-key="save"]': 'save',
'click [data-key="cancel"]': 'cancel'
},
initialize: function (options) {
var that = this;
_.bindAll(this, 'save', 'cancel');
app.Collections.quotesCategories.on('change add', function () {
that.remove();
});
},
render: function () {
var that = this;
// boilerplate render code
return this;
}
});
If someone could show me how I can convert this into a CommonJS module to be used with Browserify, then I would be very grateful and it'd really help me understand how I go about modularising the rest of the application! Thanks

//once you get things into folders/files, this path may change
//but for now I'm assuming all your views will live in the same directory
var ModalView = require('./modal-view');
var QuoteCategoriesEdit = ModalView.extend({
className: '',
template: JST["templates/quotes/categories/quote-categories-edit.html"],
events: {
'click [data-key="save"]': 'save',
'click [data-key="cancel"]': 'cancel'
},
initialize: function (options) {
var that = this;
_.bindAll(this, 'save', 'cancel');
app.Collections.quotesCategories.on('change add', function () {
that.remove();
});
},
render: function () {
var that = this;
// boilerplate render code
return this;
}
});
//Simplest convention is just 1-class-per-module
//Just export the constructor function
module.exports = QuoteCategoriesEdit;
Follow-up question from the comments:
Very much appreciate this! How would you approach: app.Collections.quotesCategories as I house everything under the app namespace? Do I just require the Collection itself?
So the idea of an "app" namespace is the opposite of being modular/commonjs/browserify/requirejs. You don't need an app object anymore. Any module that needs to create a new instance of this collection would just do var QuotesCategories = require('app/collections/quotes-categories'); and that is all. No more globals or namespace objects. Mostly your views will get the models/collections they need in their constructor function options. Most of your models will get created by calling fetch on a collection, and most of your collections will be instantiated by your router.
Oh, and yes in this specific example it's probably best if non-view code creates the collection and passes it to the view via the constructor options.collection parameter. However, if you decided yes you really wanted your view to instantiate the collection, it wouldn't come from the app global namespace object, it would just come from a require call as you describe in your comment.

Related

How to properly use Marionette layouts?

my current code looks like this:
define([
'jquery',
'underscore',
'backbone',
'marionette',
'templates',
'gridView',
'detailView',
'detailModel'
], function ($, _, Backbone, Marionette, JST, GridView, DetailView, DetailModel) {
'use strict';
return Marionette.Layout.extend({
el: '#main',
template: JST['app/scripts/templates/main.ejs'],
initialize: function() {
this.render();
},
onRender: function () {
var Layout = Marionette.Layout.extend({
el: 'div',
template: _.template(""),
regions: {
grid: '#grid',
detail: '#detail'
}
});
this.layout = new Layout();
this.layout.render();
},
showGrid: function () {
var detailModel = new DetailModel();
var g = new GridView(detailModel);
var d = new DetailView(detailModel);
this.layout.grid.show(g);
this.layout.detail.show(d);
}
});
});
What I do not understand is why I need an extra layout in my onRender method to make this work. The '#grid' and '#detail' divs are part of the main.ejs template, but the following does not work:
return Marionette.Layout.extend({
el: '#main',
template: JST['app/scripts/templates/main.ejs'],
regions: {
grid: '#grid',
detail: '#detail'
},
initialize: function() {
this.render();
},
onRender: function () {
var detailModel = new DetailModel();
var g = new GridView(detailModel);
var d = new DetailView(detailModel);
this.grid.show(g);
this.detail.show(d);
}
});
It seems that the layout only works if the elements specified in the region object already exist when the layout is created. But the documentation says that this is not the case.
I'm probably doing something wrong. But what ?
Regards
Roger
In your second code example, try using onShow instead of onRender.
In addition, in Marionette you usually don't call render yourself, since the framework will call that method when you pass view/layouts to the show method.
You can see a different take on what you're trying to accomplish here :
https://github.com/davidsulc/marionette-gentle-introduction/blob/master/assets/js/apps/contacts/list/list_controller.js (particularly lines 43-46)
As an additional warning, calling .show() in the onRender method can negatively impact anything nested below that layout, especially if you are trying to use onShow later down the line to ensure that a view's DOM subtree is jQuery accessible.
.show() triggers a "show" event across any subviews of that layout and can mean that onShow() is called in those subviews (which listen for the "show" event) before those subviews have rendered and inserted their content.

Creating backbone views with models from other views

Background:
I am making changes to an application that uses backbone.js with Handlebars as the templating engine. After a change event fires I need to create html that is appended to the current DOM structure which is basically just a spit-out of information that is contained in the model. This change needed to fit in the already established application structure.
Issue:
I have created a new view that uses a Handlebars template and the model to create the html. I then instantiate that view and call the render function and append the output using JQuery. What I am noticing is that when the html is rendered the model that is passed in because attributes on the $el instead of filling in the template (like I think it should).
View I'm altering:
$.hart.TestView = Backbone.View.extend({
tagName: "li",
template: Handlebars.compile($('#templateOne').html()),
initialize: function () {
this.model.on('change', function () {
this.createMoreInfoHtml();
}, this);
},
selectSomething: function () {
this.$el.removeClass('policies');
this.createMoreInfoHtml(); //function created for new view stuff
},
createMoreInfoHtml: function () {
var id = this.$el.attr('data-id', this.model.get("ID"));
$('.info').each(function () {
if ($(this).parent().attr('data-id') == id
$(this).remove();
});
var view = new $.hart.NewView(this.model, Handlebars.compile($("#NewTemplate").html()));
$('h1', this.$el).after(view.render().el);
},
render: function () {
... //render logic
}
});
View I Created:
$.hart.NewView = Backbone.View.extend({
initialize: function (model, template) {
this.model = model;
this.template = template;
},
render: function () {
this.$el.html(this.template({ info: this.model }));
this.$el.addClass('.info');
return this;
}
});
Json the is the model:
{
"PetName":"Asdfasdf",
"DateOfBirth":"3/11/2011 12:00:00 AM",
"IsSpayNeutered":false,
"Sex":"F",
"SpeciesID":2,
"ID":"ac8a42d2-7fa7-e211-8ef8-000c2964b571"
}
The template
<script id="NewTemplate" type="text/html">
<span>Pet Name: </span>
<span>{{this.PetName}}</span>
</script>
So now to the question: What am I doing wrong? Why are the properties of the model being created as attributes on the $el instead of filling in the template? Can someone please direct me as to how to get the results I am looking for?
Let's skip the problem Jack noticed.
The way you're creating your view is just wrong. It may work as you get the expected arguments in the initialize function, but it has unexpected behaviors you don't see. See the View's constructor:
var View = Backbone.View = function(options) {
this.cid = _.uniqueId('view');
this._configure(options || {});
Now let's have a look at this _configure method:
_configure: function(options) {
if (this.options) options = _.extend({}, _.result(this, 'options'), options);
_.extend(this, _.pick(options, viewOptions));
And of course...
var viewOptions = ['model', 'collection', 'el', 'id', 'attributes', 'className', 'tagName', 'events'];
Ok here we are... Basically when passing the model as the options argument, you're passing an object with an attributes key (the attributes of your model). But this attributes key is also used in the View to bind attributes to its element! Therefore the behavior your noticed.
Now, other wrong thing. You're compiling your template each time you create a new function, but not using it as a singleton either. Put your template in the view:
$.hart.NewView = Backbone.View.extend({
template: Handlebars.compile($("#NewTemplate").html(),
And change your view's creation to make the whole thing work:
new $.hart.NewView({model: this.model});
Oh, and get rid of this useless initialize method. You're just doing things Backbone already does.

Backbone boilerplate: "this.model is undefined"

I'm a backbone newbie, so I'm sort of fumbling on getting an app set up. I'm using the backbone-boilerplate (https://github.com/tbranyen/backbone-boilerplate) and github-viewer (https://github.com/tbranyen/github-viewer) as a reference, though when running I seem to be getting a "this.model is undefined".
Here is my current router.js:
define([
// Application.
"app",
//Modules
"modules/homepage"
],
function (app, Homepage) {
"use strict";
// Defining the application router, you can attach sub routers here.
var Router = Backbone.Router.extend({
initialize: function(){
var collections = {
homepage: new Homepage.Collection()
};
_.extend(this, collections);
app.useLayout("main-frame").setViews({
".homepage": new Homepage.Views.Index(collections)
}).render();
},
routes:{
"":"index"
},
index: function () {
this.reset();
this.homepage.fetch();
},
// Shortcut for building a url.
go: function() {
return this.navigate(_.toArray(arguments).join("/"), true);
},
reset: function() {
// Reset collections to initial state.
if (this.homepage.length) {
this.homepage.reset();
}
// Reset active model.
app.active = false;
}
});
return Router;
}
);
And my homepage.js module:
define([
"app"
],
function(app){
"use strict";
var Homepage = app.module();
Homepage.Model = Backbone.Model.extend({
defaults: function(){
return {
homepage: {}
};
}
});
Homepage.Collection = Backbone.Collection.extend({
model: Homepage.Model,
cache: true,
url: '/app/json/test.json',
initialize: function(models, options){
if (options) {
this.homepage = options.homepage;
}
}
});
Homepage.Views.Index = Backbone.View.extend({
template: "homepage",
el: '#mainContent',
render: function(){
var tmpl = _.template(this.template);
$(this.el).html(tmpl(this.model.toJSON()));
return this;
},
initialize: function(){
this.listenTo(this.options.homepage, {
"reset": function(){
this.render();
},
"fetch": function() {
$(this.el).html("Loading...");
}
});
}
});
return Homepage;
});
Thanks in advance for the help!
Update: After much googling (you should see how many tabs I have open), I think I made a little bit of headway, but still no luck. I updated my router to have the following:
app.useLayout("main-frame").setViews({
".homepage": new Homepage.Views.Index()
}).render();
I made a number of modifications to my homepage.js module to now look like this:
define([
"app",
["localStorage"]
],
function(app){
"use strict";
var Homepage = app.module();
Homepage.Model = Backbone.Model.extend({
defaults: function(){
return {
homepage: {}
};
}
});
Homepage.Collection = Backbone.Collection.extend({
//localStorage: new Backbone.LocalStorage("Homepage.Collection"),
refreshFromServer: function() {
return Backbone.ajaxSync('read', this).done( function(data){
console.log(data);
//save the data somehow?
});
},
model: Homepage.Model,
cache: true,
url: '/app/json/test.json',
initialize: function(options){
if (options) {
this.homepage = options.homepage;
}else{
//this.refreshFromServer();
}
}
});
Homepage.Views.Index = Backbone.View.extend({
template: "homepage",
el: '#mainContent',
initialize: function(){
var self = this;
this.collection = new Homepage.Collection();
this.collection.fetch().done( function(){
self.render();
});
},
render: function(){
var data = this.collection;
if (typeof(data) === "undefined") {
$(this.el).html("Loading...");
} else {
$(this.el).html(_.template(this.template, data.toJSON()));
}
return this;
}
});
return Homepage;
});
As you can see, I have localStorage code but commented out for now because I just want to get everything working first. The ultimate goal is to have an initial call that loads data from a JSON file, then continues afterwards using localStorage. The app will later submit data after the user does a number of interactions with my app.
I am getting the main view to load, though the homepage module isn't populating the #mainContent container in the main view.
I did all of the googling that I could but frustrated that it's just not sinking in for me. Thanks again for looking at this and any feedback is appreciated!
I think your class hierarchy is a bit wonky here. Your instance of Homepage.Collection is actually assigning a homepage property out of options, for instance. Then you pass an instance of Homepage.Collection into Homepage.Views.Index as the homepage option... It's a bit hard to follow.
That said, it seems to me your problem is simply that you aren't supply a model option when you construct your Homepage.Views.Index:
new Homepage.Views.Index(collections)
collections doesn't have a model property, and thus I don't see how this.model.toJSON() later on in the view can have a model to access. Basically, you seem to want Homepage.Views.Index to handle a collection of models, not just one. So you probably need a loop in your render function that goes over this.collection (and you should change your construction of the view to have a collection option instead of homepage option).
If I'm missing something here or I'm unclear it's because of this data model oddness I mentioned earlier. Feel free to clarify how you've got it reasoned out and we can try again :)
This example code you have is a little bit confusing to me, but I think the problem lies in the following two lines of code:
".homepage": new Homepage.Views.Index(collections)
$(this.el).html(tmpl(this.model.toJSON()));
It looks like you pass a collection to the view, but in the view you use this.model, hence the error "this.model is undefined", since it is indeed undefined.
If you aren't in any rush, may I suggest that you start over. It seems you are trying too much too quickly. I see that you have backbone, requirejs (or some other module loader), and the boilerplate, which is a lot to take in for someone new to backbone. Trust me, I know, because I am relatively new, too. Maybe start with some hello world stuff and slowly work your way up. Otherwise, hacking your way through bits of code from various projects can get confusing.

Accessing collection in multiple views - Backbone + RequireJS

I am working on my first RequireJS/Backbone app and I've hit a wall. There's a lot of code smell here, and I know I'm just missing on the pattern.
I have a route that shows all promotions, and one that shows a specific promotion (by Id):
showPromotions: function () {
var promotionsView = new PromotionsView();
},
editPromotion: function (promotionId) {
vent.trigger('promotion:show', promotionId);
}
In my promotions view initializer, I new up my PromotionsCollection & fetch. I also subscribe to the reset event on the collection. This calls addAll which ultimately builds a ul of all Promotions & appends it to a container div in the DOM.
define([
'jquery',
'underscore',
'backbone',
'app/vent',
'models/promotion/PromotionModel',
'views/promotions/Promotion',
'collections/promotions/PromotionsCollection',
'text!templates/promotions/promotionsListTemplate.html',
'views/promotions/Edit'
], function ($, _, Backbone, vent, PromotionModel, PromotionView, PromotionsCollection, promotionsListTemplate, PromotionEditView) {
var Promotions = Backbone.View.extend({
//el: ".main",
tagName: 'ul',
initialize: function () {
this.collection = new PromotionsCollection();
this.collection.on('reset', this.addAll, this);
this.collection.fetch();
},
render: function () {
$("#page").html(promotionsListTemplate);
return this;
},
addAll: function () {
//$("#page").html(promotionsListTemplate);
this.$el.empty().append('<li class="hide hero-unit NoCampaignsFound"><p>No campaigns found</p></li>');
this.collection.each(this.addOne, this);
this.render();
$("div.promotionsList").append(this.$el);
},
addOne: function (promotion) {
var promotionView = new PromotionView({ model: promotion });
this.$el.append(promotionView.render().el);
}
});
return Promotions;
});
Each promotion in the list has an edit button with a href of #promotion/edit/{id}. If I navigate first to the list page, and click edit, it works just fine. However, I cannot navigate straight to the edit page. I understand this is because I'm populating my collection in the initialize method on my View. I could have a "if collection.length == 0, fetch" type of call, but I prefer a design that doesn't have to perform this kind of check. My questions:
How do I make sure my collection is populated regardless of which route I took?
I'm calling render inside of my addAll method to pull in my template. I could certainly move that code in to addAll, but overall this code smells too. Should I have a "parent view" that's responsible for rendering the template itself, and instantiates my list/edit views as needed?
Thanks!
Here's one take. Just remember that there is more than one way to do this. In fact, this may not be the best one, but I do this myself, so maybe someone else can help us both!
First off though, you have a lot of imports in this js file. It's much easier to manage over time as you add/remove things if you import them like this:
define(function( require ){
// requirejs - too many includes to pass in the array
var $ = require('jquery'),
_ = require('underscore'),
Backbone = require('backbone'),
Ns = require('namespace'),
Auth = require('views/auth/Auth'),
SideNav = require('views/sidenav/SideNav'),
CustomerModel = require('models/customer/customer');
// blah blah blah...});
That's just a style suggestion though, your call. As for the collection business, something like this:
Forms.CustomerEdit = Backbone.View.extend({
template: _.template( CustomerEditTemplate ),
initialize: function( config ){
var view = this;
view.model.on('change',view.render,view);
},
deferredRender: function ( ) {
var view = this;
// needsRefresh decides if this model needs to be fetched.
// implement on the model itself when you extend from the backbone
// base model.
if ( view.model.needsRefresh() ) {
view.model.fetch();
} else {
view.render();
}
},
render:function () {
var view = this;
view.$el.html( view.template({rows:view.model.toJSON()}) );
return this;
}
});
CustomerEdit = Backbone.View.extend({
tagName: "div",
attributes: {"id":"customerEdit",
"data-role":"page"},
template: _.template( CustomerEditTemplate, {} ),
initialize: function( config ){
var view = this;
// config._id is passed in from the router, as you have done, aka promotionId
view._id = config._id;
// build basic dom structure
view.$el.append( view.template );
view._id = config._id;
// Customer.Foo.Bar would be an initialized collection that this view has
// access to. In this case, it might be a global or even a "private"
// object that is available in a closure
view.model = ( Customer.Foo.Bar ) ? Customer.Foo.Bar.get(view._id) : new CustomerModel({_id:view._id});
view.subViews = {sidenav:new Views.SideNav({parent:view}),
auth:new Views.Auth(),
editCustomer: new Forms.CustomerEdit({parent:view,
el:view.$('#editCustomer'),
model:view.model})
};
},
render:function () {
var view = this;
// render stuff as usual
view.$('div[data-role="sidetray"]').html( view.subViews.sidenav.render().el );
view.$('#security').html( view.subViews.auth.render().el );
// magic here. this subview will return quickly or fetch and return later
// either way, since you passed it an 'el' during init, it will update the dom
// independent of this (parent) view render call.
view.subViews.editCustomer.deferredRender();
return this;
}
Again, this is just one way and might be terribly wrong, but it's how I do it and it seems to work great. I usually put a "loading" message in the dom where the subview eventually renders with replacement html.

Backbone.js event after view.render() is finished

Does anyone know which event is fired after a view is rendered in backbone.js?
I ran into this post which seems interesting
var myView = Backbone.View.extend({
initialize: function(options) {
_.bindAll(this, 'beforeRender', 'render', 'afterRender');
var _this = this;
this.render = _.wrap(this.render, function(render) {
_this.beforeRender();
render();
_this.afterRender();
return _this;
});
},
beforeRender: function() {
console.log('beforeRender');
},
render: function() {
return this;
},
afterRender: function() {
console.log('afterRender');
}
});
Or you can do the following, which is what Backbone code is supposed to look like (Observer pattern, aka pub/sub). This is the way to go:
var myView = Backbone.View.extend({
initialize: function() {
this.on('render', this.afterRender);
this.render();
},
render: function () {
this.trigger('render');
},
afterRender: function () {
}
});
Edit: this.on('render', 'afterRender'); will not work - because Backbone.Events.on accepts only functions. The .on('event', 'methodName'); magic is made possible by Backbone.View.delegateEvents and as such is only available with DOM events.
As far as I know - none is fired. Render function is empty in source code.
The default implementation of render is a no-op
I would recommend just triggering it manually when necessary.
If you happen to be using Marionette, Marionette adds show and render events on views. See this StackOverflow question for an example.
On a side note, Marionette adds a lot of other useful features that you might be interested in.
I realise this question is fairly old but I wanted a solution that allowed the same custom function to be called after every call to render, so came up with the following...
First, override the default Backbone render function:
var render = Backbone.View.prototype.render;
Backbone.View.prototype.render = function() {
this.customRender();
afterPageRender();
render();
};
The above code calls customRender on the view, then a generic custom function (afterPageRender), then the original Backbone render function.
Then in my views, I replaced all instances of render functions with customRender:
initialize: function() {
this.listenTo(this.model, 'sync', this.render);
this.model.fetch();
},
customRender: function() {
// ... do what you usually do in render()
}
Instead of adding the eventhandler manually to render on intialization you can also add the event to the 'events' section of your view. See http://backbonejs.org/#View-delegateEvents
e.g.
events: {
'render': 'afterRender'
}
afterRender: function(e){
alert("render complete")
},
constructor: function(){
Backbone.View.call(this, arguments);
var oldRender = this.render
this.render = function(){
oldRender.call(this)
// this.model.trigger('xxxxxxxxx')
}
}
like this http://jsfiddle.net/8hQyB/

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