Develop Reference

Uncaught Type Error: View is not a constructor

I have Uncaught Type Error : UserRegisterView is not a constructor.I dont understand this error.I looked all code but i dont find it.
Sorry of my bad english.Please help me
Thanks for answer
UPDATED
UserRegisterView is here
var UserRegisterView = Backbone.View.extend({
model: User,
el: '#form',
events: {
'click input[id="infoWeek"]': 'infoWeek',
'click input[id="infoMonth"]': 'infoMonth'
},
infoWeek: function() {
this.$el.find("#dayOfMonth").hide();
this.render();
},
infoMonth: function() {
this.$el.find("#dayOfWeek").hide();
this.render();
}
});
var AddUserView = Backbone.View.extend({
el: $(".page"),
events: {
'click #saveUser': 'saveUser'
},
saveUser: function() {
var user = new User();
user.set({
username: $("#username").val(),
lastName: $("#lastName").val(),
regNumber: $("#regNumber").val(),
password: $("#password").val(),
departmentName: $("#departmentName").val(),
email: $("#email").val(),
role: $("#role").val()
});
user.save();
if (document.getElementById('isOpen').checked) {
user.set("isOpen", $("#isOpen").val("1"));
user.save();
} else {
user.set("isOpen", $("#isOpen").val("0"));
user.save();
}
if (document.getElementById('dayOfWeek').checked) {
user.set("dayOfWeek", $("#dayOfWeek").val());
user.save();
} else if (document.getElementById('dayOfMonth').checked) {
user.set("dayOfMonth", $("#dayOfMonth").val());
user.save();
}
$("#username").val("");
$("#firstName").val("");
$("#lastName").val("");
$("#regNumber").val("");
$("#password").val("");
$("#deparmentName").val("");
$("#email").val("");
$("#isOpen").val("");
$("#dayOfWeek").val("");
$("#dayOfMonth").val("");
},
render: function() {
var that = this;
var template = Handlebars.compile(UserRegister);
var myHtml = template(that.model.toJSON());
that.$el.html(myHtml);
return this;
}
});
return {
AddUserView: AddUserView,
UserRegisterView: UserRegisterView
};
});
router user func.
define([
'jquery',
'underscore',
'backbone',
'handlebars',
'spin',
'app/models/LoginModel',
'app/views/LoginView',
'app/views/UserRegisterView'
], function($,
_,
Backbone,
Handlebars,
Spinner,
Login,
LoginView,
UserRegisterView
) {
var Router = Backbone.Router.extend({
routes: {
'search': 'search',
'login': 'login',
'travels': 'travels',
'user': 'user',
'menu': 'menu',
'': 'home'
},
user: function() {
disposeView(new UserRegisterView().render());
}
dispose.view on util.js
function disposeView(view) {
Backbone.View.prototype.close = function() {
this.unbind();
this.undelegateEvents();
};
/* Şu anki viewi yok et */
if (this.currentView !== undefined) {
this.currentView.close();
}
/* Yeni view oluştur. */
this.currentView = view;
this.currentView.delegateEvents();
return this.currentView;
}

What's happening
Your UserRegisterView module returns an object which contains two constructors.
return {
AddUserView: AddUserView,
UserRegisterView: UserRegisterView
};
When using this module, what you're getting is the object above.
define([
// ...
'app/views/UserRegisterView'
], function(
// ...
UserRegisterView // value of the return in the module
) {
So you're kind of misleading yourself by calling it UserRegisterView as it's not the constructor, but the object containing the constructor.
To get a new UserRegisterView view instance with the current way your module is setup, you'd need to call it like so:
var userView = new UserRegisterView.UserRegisterView();
Or to create a AddUserView instance:
var addView = new UserRegisterView.AddUserView();
Solutions
Split up the module, one for each view constructor.
Change the name so at least it's not misleading (like UserViewsModule)
Other improvements
That being said, there are other improvements that could be made to your Backbone code.
var UserRegisterView = Backbone.View.extend({
// that's useless (if not used) and not a view property.
// model: User,
// don't use `el` like that, especially when using the view as a shared Constructor
el: '#form',
events: {
'click input[id="infoWeek"]': 'onInfoWeekClick',
'click input[id="infoMonth"]': 'onInfoMonthClick'
},
initialize: function() {
// Cache jQuery object of the view's element
this.$dayOfMonth = this.$("#dayOfMonth");
this.$dayOfMonth = this.$("#dayOfMonth");
// also use the shortcut function instead of `this.$el.find()`
}
onInfoWeekClick: function(e) {
this.$dayOfMonth.hide();
// calling render here is useless unless your using it as a parent
// view, where the child view overrides the render function.
},
onInfoMonthClick: function(e) {
this.$dayOfMonth.hide();
}
});
The disposeView function could be simplified:
function disposeView(view) {
var current = this.currentView;
if (current) current.close();
current = this.currentView = view;
current.delegateEvents();
return current;
}
Don't change the default Backbone view prototype each time the function is called. Instead, add the function once.
_.extend(Backbone.View.prototype, {
close: function() {
this.unbind();
this.undelegateEvents();
},
// any other function you want to add can go here.
});
In another answer, I go into details on how to extend Backbone's core classes with requirejs transparently.
You're already using jQuery, so don't use JavaScript DOM API document.getElementById('isOpen') interspersed with jQuery selectors $('#isOpen').
I made some improvements to the following view. Take the time to create yourself some utility functions (like reset and getValues) to simplify the flow of the code and encapsulate the complexity.
var AddUserView = Backbone.View.extend({
el: $(".page"),
events: {
'click #saveUser': 'saveUser'
},
// compile the template once while creating the view class
template: Handlebars.compile(UserRegister),
// get the selector string out of the code and place them in one place
// easy to change and maintain.
fields: {
username: "#username",
firstName: "#firstName",
lastName: "#lastName",
regNumber: "#regNumber",
password: "#password",
deparmentName: "#deparmentName",
email: "#email",
isOpen: "#isOpen",
dayOfWeek: "#dayOfWeek",
dayOfMonth: "#dayOfMonth",
},
render: function() {
this.$el.html(this.template(this.model.toJSON()));
// cache jQuery object of every field once after a render
this.field = _.reduce(this.fields, function(fields, selector, key) {
fields['$' + key] = this.$(selector);
return fields;
}, {}, this);
return this;
},
reset: function() {
// reset all the fields once without repeating code.
_.each(this.field, function($field) {
$field.val("");
});
return this;
},
getValues: function(keys) {
// get the value of multiple fields returned in a nice object
// ready to be sent to a Backbone model.
return _.reduce(keys, function(data, key) {
data[key] = this.field[key].val();
return data;
}, {}, this);
},
saveUser: function() {
var field = this.field,
user = new User(this.getValues([
'username',
'lastName',
'regNumber',
'password',
'departmentName',
'email',
'role',
]));
user.set({ isOpen: field.$isOpen.is(':checked') });
if (field.$dayOfWeek.is(':checked')) {
user.set("dayOfWeek", field.$dayOfWeek.val());
} else if (field.$dayOfMonth.is(':checked')) {
user.set("dayOfMonth", field.$dayOfMonth.val());
}
user.save();
this.reset();
},
});
In the following snippet, you're putting the context (this) into a local variable. I see that a lot and I could say that 90% of the times I see it on Stack Overflow questions, it makes no sense. It clearly screams copy-pasted.
render: function() {
var that = this;
// ...
that.$el.html(myHtml);
return this;
}
Please tell me you see that you're putting this into that, then using that throughout the function, then you still return this?!
Putting the context into a local variable is useful when the object is needed in a dynamically created callback.
render: function() {
var that = this; // this is available here
setTimeout(function() {
// here this is not available.
that.handleCallback();
}, 10);
// here we are in the same context as the first line.
return this;
}

Backbone create a new view instance every request page

In my App i have created a View. this View is composed of a Template like a little Form. The Form has an button and in my View i create an click event to handle this button to create a new instance of another View passing the Form data to this View and put the data on html element. The problem is: if i enter in home route or in product 3 times and send a Form data, will appears 3 same Form datas.
Form view
window.userFormView = Backbone.View.extend({
el:$("#principal"),
events : {
'click .userButton' : 'newUser'
},
initialize:function(){
this.template = _.template($("#userFormView").html());
},
newUser : function(ev) {
ev.preventDefault();
//criamos uma nova instancia do model
window.user_view = new userViewes({model: users});
var u = { nome : $("#iName").val() ,sobrenome : $("#iLName").val() };
var user = new userModel(u);
users.add(user);
console.log(users);
return false;
},
render: function() {
this.$el.html("");
this.$el.html(this.template);
}
});
Form Template View
<script type="text/template" id="userFormView">
<form action="" id="form-new-user" class="formulario">
<span class="label">Name?</span><input type="text" id="iName" class="input">
<span class="label">Last Name?</span><input type="text" id="iLName" class="input">
<button class="userButton">Send</button>
<hr>
</form>
</script>
and my route are like this:
window.AppRouter = Backbone.Router.extend({
//
// Definindo rotas
//
routes: {
'home': 'index',
'product': 'productsList',
'foo1': 'doNothing1',
'foo2': 'doNothing2'
},
index: function () {
window.users = new userCollections();
window.userForm = new userFormView();
},
productsList : function() {
window.pCollection = new productCollections();
window.produtoForm = new produtoFormView();
},
doNothing1: function () {
console.log('doNothing1()');
},
doNothing2: function () {
console.log('doNothing2()');
}
});
window.router = new AppRouter();
Backbone.history.start();
userViewes view
window.userViewes = Backbone.View.extend({
// model: users,
el: $("#userContainer"),
initialize: function(){
this.model.on("add", this.render, this);
this.model.on("remove", this.render, this);
},
render: function() {
var self = this;
self.$el.html("");
this.model.each(function(user, indice) {
self.$el.append((new userView({model: user })).render().$el);
});
return this;
}
});
and finally userView:
window.userView = Backbone.View.extend({
//model: new userModel(),
tagName : 'div',
class : "userName",
events :{
'click .editar' : 'editar',
'click .remover' : 'remover',
'blur .sobrenome': 'fechar',
'keypress .sobrenome' : 'onEnterUpdate',
},
editar : function(ev) {
ev.preventDefault();
this.$('.sobrenome').attr('contenteditable', true).focus();
},
fechar : function(ev) {
var sobrenome = $(".sobrenome").text();
this.model.set("sobrenome", sobrenome);
$(".sobrenome").val();
this.$(".sobrenome").removeAttr("contenteditable");
},
onEnterUpdate : function(ev) {
var self = this;
if(ev.keyCode == 13) {
self.fechar();
_.delay(function(){
self.$(".sobrenome").blur();
}, 100);
}
},
remover : function(ev) {
ev.preventDefault();
window.users.remove(this.model);
},
initialize: function(){
this.template = _.template($("#userTemplate").html());
},
render : function() {
this.$el.html(this.template(this.model.toJSON()));
return this;
}
});

When your view is using el option, make sure you clean up the existing view before you make a new one.
As it is, every time you switch between routes (without a full page refresh) a new instance pointing to same element is created which causes more and more event handlers to be bound to the el element which is in DOM, and the views stay in memory because of the binding. Try something like:
index: function () {
window.users = window.users || new userCollections();
if(window.userForm){
// clean up is important
window.userForm.remove();
}
window.userForm = new userFormView();
},
And of course, instead of repeating similar code in all routes, have a variable like this.currentView that points to the active view, and a common function that does necessary clean up
P.S: Adding properties to window object is a bad practice. Create your own name space or use the Router instance instead of window

I have found the answer. i implemented singleton pattern to get only one instance of the object. follow the code:
var single = (function(){
function createInstance() {
window.userForm = new userFormView();
window.users = new userCollections();
}
function users() {
return window.users;
}
function userForm() {
return window.userForm;
}
return {
init : function() {
if(!window.users && !window.userForm) {
createInstance();
}else{
this.render();
}
},
render: function() {
window.userForm.render();
}
}
}());
single.init();

Backbone: not correct view after redirect

I am new to Backbone and have an issue from almous beginning wondering how to overcome issue with unexpected behavior of a main view.
1. I launch page and it looks okey.
2. I click button that lead me to different view and shows me it well.
3. I click "back" button and I see a blank page, but in DOM I can find some elements from previous view, but not visible.
Here is a piece of my router code (I hope this pieces will be enough):
home: function () {
if (!app.leftMenuView) {
app.leftMenuView = new app.views.LeftMenuView({
el: $("#left_menu")
});
} else {
app.leftMenuView.delegateEvents();
}
if (!app.homeView) {
app.homeView = new app.views.HomeView({
el: $("#main_container")
});
} else {
app.homeView.delegateEvents();
}
if (!app.topMenuView) {
app.topMenuView = new app.views.topMenuView({
el: $("#top_menu")
});
} else {
app.topMenuView.delegateEvents();
}
},
search: function () {
app.searchView = new app.views.SearchView({
el: $("body")
});
},
A piece of main html file:
<body>
<div id="search-div"></div>
...
</body>
HomeView:
app.views.HomeView = Backbone.View.extend({
initialize: function () {
this.render()
},
render: function () {
var self = this;
$.get('/template/home.html', function (data) {
self.$el.html(_.template(data)({}));
});
return this;
},
});
A SearchView:
app.views.SearchView = Backbone.View.extend({
events: {
"click #left-arrow-icon": "toMainPage"
},
initialize: function () {
this.render();
},
render: function () {
var self = this;
$.get('/template/searchView.html', function (data) {
self.$el.html(_.template(data));
});
return this;
},
toMainPage: function () {
Backbone.history.history.back();
},
});

In the example provided, the search view, if rendered, will destroy the main html file content since the element provided is directly the body. In any case, if you go to search view, your home page will have been destroyed or will not be able to render anymore.
I would suggest an improved layout management :
separate elements per views
show/hide of root elements based on routes

Backbone: how to get and display just one model data in a view via router

I have created a very basic backbone app, to understand how it works.
In the router, I just wanna display just 1 model, i.e. a user, not the whole collection, by passing an id in the url, how to do that?
For example, I'd like to do someapp.com/app/#user/2, and this would display just user no2 details.
Please see my work in jsfiddle
// router
var ViewsRouter = Backbone.Router.extend({
routes: {
'': 'viewOne',
'one': 'viewOne',
'two': 'viewTwo',
'user/:id': 'user'
},
viewOne: function() {
var view = new TheViewOne({ model: new TheModel });
},
viewTwo: function() {
var view = new UserView({ model: new TheModel });
},
user: function(id) {
// how to get just 1 user with the corresponding id passed as argument
// and display it???
}
});
Many thanks.

https://github.com/coding-idiot/BackboneCRUD
I've written a complete Backbone CRUD with no backend stuff for beginners. Below is the part where we get the user from the collection and show/render it.
View
var UserEditView = Backbone.View.extend({
render: function(options) {
if (options && options.id) {
var template = _.template($("#user-edit-template").html(), {
user: userCollection.get(options.id)
});
this.$el.html(template);
} else {
var template = _.template($("#user-edit-template").html(), {
user: null
});
// console.log(template);
this.$el.html(template);
}
return this;
},
Router
router.on('route:editUser', function(id) {
console.log("Show edit user view : " + id);
var userEditView = new UserEditView({
el: '.content'
});
userEditView.render({
id: id
});
});
Update
Particularly, sticking to your code, the router will look something like this :
user: function(id) {
var view = new UserView({ model: userCollection.get(id) });
}

Prevent tab contents from loading multiple times (backbone.js)

I have a few tabs on my page, whose contents (consisting of many SetView contained by SetListView) are loaded using Backbone.js whenever its tabs is being clicked on.
Problem:: When the user switches from a tab to a previously loaded/viewed tabbed, the contents load again and append to the previously loaded content in SetListView. I can get it to clear the previously loaded contents before loading it again, but it seems to be less than optimal to keep loading the same content.
Is it possible to make Backbone.js store existing content for a tab and not load it multiple times when switching back to the same tab?
Views
// Views
var SetListView = Backbone.View.extend({
el: '#set_list',
initialize: function() {
this.collection.bind('reset', this.render, this);
},
render: function() {
this.collection.each(function(set, index) {
$(this.el).append( new SetView({ model: set }).render().el );
}, this);
return this;
}
});
var SetView = Backbone.View.extend({
tagName: 'div',
className: 'photo_box',
template: _.template( $('#tpl_SetView').html() ),
initialize: function() {
this.model.on('destroy', this.close, this);
},
render: function() {
$(this.el).html( this.template( this.model.toJSON() ) );
return this;
},
close: function() {
this.unbind();
this.remove();
}
});
Router
// Router
var AppRouter = Backbone.Router.extend({
routes: {
'': 'sets',
'sets': 'sets'
},
viewing_user_id: $('#viewing_user_id').val(),
sets: function() {
this.showTab('sets');
this.setList = new SetCollection();
this.setListView = new SetListView({ collection: this.setList });
var self = this;
this.setList.fetch({
data: {user_id: self.viewing_user_id},
processData: true
});
},
showTab: function(tab) {
// Show/hide tab contents
$('.tab-content').children().not('#tab_pane_' + tab).hide();
$('.tab-content').children('#tab_pane_' + tab).fadeIn('fast');
// Activate/deactivate tabs
$('#tab_' + tab).addClass('active');
$('#tab_' + tab).siblings().removeClass('active');
}
});

Backbone has not any in-house system to difference between when you want to re-fetch the content or re-using the already fetched one. You have to decide when do each of this actions.
A modification of your example code to achieve this can be:
var AppRouter = Backbone.Router.extend({
// ... more router code
sets: function() {
if( !this.setList ) this.initializeSets();
this.showTab('sets');
},
initializeSets: function(){
this.setList = new SetCollection();
this.setListView = new SetListView({ collection: this.setList });
var self = this;
this.setList.fetch({
data: {user_id: self.viewing_user_id},
processData: true
});
},
});
So you only call initializeSets() if they are not already initialized. Of course will be more elegant and clean ways to ask if the sets have been initialized but this is up to you.