"Backendless is not defined"

General
1

Hi,

I just started migrating my app to Backendless 4.x. Everything seems to be working on most of my team’s computers, but we’re suddenly unable to pull up the website on 1 machine. Both Chrome & Safari are throwing errors.

Chrome:

Your data cannot be processed. Please refresh the page. Error message: Uncaught ReferenceError: Backendless is not defined

Safari

Your data cannot be processed. Please refresh the page. Error message: ReferenceError: Can't find variable: Backendless

Does anyone know what the problem is here? We haven’t changed a single character of code.

Thanks,
Casey

2

Hi Casey,

How do you reference the Backendless library/js in your code?

Regards,
Mark

3

Mark,

In the head of our index.php file, we reference it via a simple script tag:

<<script src="http://api.backendless.com/sdk/js/v3/backendless.min.js"></script>

Above that, we have another script that reads:

document.addEventListener("DOMContentLoaded", function(event) {
Backendless.initApp(.....
4

Casey,

Version 4 of the Backendless backend requires that you use version 4 of the library. Here’s the doc:
https://backendless.com/docs/js/doc.html#setup

Regards,
Mark

5

Ah yes. But the site is still running on v3 of Backendless, so that library should still work.

And, it does on everything except that one machine

6

If you call Backendless.initApp before the js is loaded, it would explain the error.

7

Huh. Any idea why it wasn’t a problem before?

8

I am not sure, but the sequence certainly makes sense (load library first, then start using it).

9

Agreed. And now it seems to be working.

Thanks Mark!