How to fix Uncaught TypeError: Cannot read property 'prototype' of undefined?

javascript jquery backbone.js

107,365

Solution 1

I fixed this bug. The problem was that I created Collection and then the Model. Collections use user model, as working unit, but when I defined this Collection, I did not define Model.

So, if you want to avoid this bug, firstly define a Model and only then define the Collection.

Solution 2

Backbone Js has dependency with underscore.js and jQuery, try reordering the resources. This worked for me:

<head>
    <title>Backbone</title>

    <!-- Scripts Load Here-->       
    <script type="text/javascript" src="js/jquery-1.11.0.min.js"></script>
    <script type="text/javascript" src="js/underscore.js"></script>
    <script type="text/javascript" src="js/backbone.js"></script>
</head>

Solution 3

In my case, the following imports are incorrect: (react)

// remove
import e from 'express';

Solution 4

In my case , imports were incorrect

import { urlencoded } from "express";
When I removed this statement , it worked for me. Check imports of the files you are working with , wheteher something unnecessary imported

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107,365

Author by

Oleksandr H

Updated on July 09, 2022

Comments

Oleksandr H almost 2 years

I have a little problem. I'm using backbone.js. I wrote this code like in example:

<script>
$(document).ready(function () {
    window.App = {
        Views: {},
        Models: {},
        Collections: {}
    }

    App.Collections.Users = Backbone.Collection.extend({
         model: App.Models.User,
         url: 'service'
    });
    App.Models.User = Backbone.Model.extend({});

    App.Views.App = Backbone.View.extend({
         initialize: function() {
             console.log( this.collection.toJSON() );
         }
    });

});
</script>

Than I started server and in browser console type this:

var x =new App.Collections.Users();
x.fetch()

And this follows to error: Uncaught TypeError: Cannot read property 'prototype' of undefined. But data is present in response. Details in picture. How to fix this? Thanks for you answers. enter image description here

enter image description here

kidnan1991 over 9 years

I see this is a correct one. due to the library import order
Sander over 9 years

This was the problem for my case as well, thanks! I am using Gulp, so if anyone's using that please check the sequence of loading.
zeros-and-ones about 9 years

Yeah I renamed the model was collection was referencing, causing this error.
ProblemsOfSumit almost 9 years

god bless StackOverflow. That error message would've never lead me to that conlusion. I'm also a victim of gulps minifying.
Guillaume Renoult over 8 years

Thanks, I had the same issue as well. I created the collection model in initialize method instead of defining it as property model of the collection.
scones about 8 years

Happened even when both were in ready blocks. Had to force a load order.
PapaHotelPapa almost 8 years

If anyone needs it, that would make your code: App.Collections.Users = Backbone.Collection.extend({ initialize: function() { user = new App.Models.User(); }, url: 'service' }); ***Only the section relevant to the change shown.
Syntaxsizer about 7 years

I had similar issue that backbone.min complaining about reading property of undefined i suspected it was a collection issue, it was import order problem lol, Thanks guys