Last Updated: 24 Feb 2021 10:04 by ADMIN
Release R1 2021 SP1
Created on: 07 Feb 2019 10:07
Type: Bug Report
An error '$.throttle is not a function' is thrown in Angular report viewer with enabled continuous scrolling

On attempt to display reports in Print Preview in Angular applications, an error is thrown if continuous scrolling is enabled.

Possible workaround: Disable continuous scrolling by setting the pageMode option to 'SINGLE_PAGE'.

Posted on: 03 Feb 2021 15:29


This issue has been reported to appear again, and this item has been reopened.

When the ReportViewer is initialized, a plugin uses the JQuery namespace to attach two method, throttle and debounce. It seems like in some cases JQuery is initialized multiple times and the two methods are no longer available in the JQuery namespace, resulting in this error.

A potential workaround is to move these two methods into their own namespace and update the references. In the current version of AngularViewer, the telerikReportViewer.js file inside the dependency folder can be modified to do this by changing the following lines:

[16]:   var $ = window.Cowboy || (window.Cowboy = {}), jq_throttle;
[1178]:   that.$pageContainer.scroll(Cowboy.throttle(250, function() { 
[1189]:   that.$pageContainer.scroll(Cowboy.debounce(250, function() {

This uses the namespace 'Cowboy', suggested as a backup in the plugin, instead of Jquery's.

Regards, Mads Progress Telerik

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Posted on: 14 Feb 2019 13:07
Hello Tony and Bilal,

This fix is included in our new Internal Build version
Please upgrade and let us know how it goes.

Best Regards,
Progress Telerik
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Posted on: 13 Feb 2019 23:31
I am also seeing this issue. I have uploaded the error.
Attached Files: