Unable to get property '_events' of undefined or null reference

12 posts, 0 answers
  1. John
    John avatar
    31 posts
    Member since:
    May 2014

    Posted 02 May 2014 Link to this post

    Hello Again,

    I am facing another issue. Again, there is a mix of controls. The problem is that c is null and an exception is thrown. I am using IE 10 to test by the way. Let me know if you require any additional information and I will post it.

    Thanks,
    John.

    ,_removeHandler:function(c,d,e){var a=null;
    var b=c._events[d]||[];
    for(var f=0,g=b.length;
    f<g;
    f++){if(b[f].handler===e){a=b[f].browserHandler;
    break;
    }}if($telerik.useDetachEvent(c)){c.detachEvent("on"+d,a);
    }else{if(c.removeEventListener){c.removeEventListener(d,a,false);
    }}b.splice(f,1);
  2. John
    John avatar
    31 posts
    Member since:
    May 2014

    Posted 02 May 2014 Link to this post

    We are using version 2014.1.403.45 of Telerik by the way!
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  4. Vessy
    Admin
    Vessy avatar
    1382 posts

    Posted 07 May 2014 Link to this post

    Hello John,

    I am afraid that the provided information was not enough for us to determine what is causing the issue. Could you, please, provide more details on the exact scenario?
    • Are there any custom JavaScript functions on the page where the error occurs?
    • Which controls are used in the page where the error occurs? Can you remove them one by one and isolate the exact one causing the error?
    • Is the error thrown on page load or there are any steps that need to be made in order to reproduce it?
    • Can you prepare a simple page reproducing the issue so we could investigate the problematic markup at hand? You may find useful information on the subject in this blog post: Isolating a problem in a sample project

    Looking forward to hearing from you,
    Vessy
    Telerik
     

    Check out the Telerik Platform - the only platform that combines a rich set of UI tools with powerful cloud services to develop web, hybrid and native mobile apps.

     
  5. John
    John avatar
    31 posts
    Member since:
    May 2014

    Posted 08 May 2014 in reply to Vessy Link to this post

    Hi Vessy,

    Thanks for your reply. I will try to isolate the issue as you have suggested. If I can, I will prepare a sample page. I will get back to you ASAP.

    Cheers,
    John.
  6. John
    John avatar
    31 posts
    Member since:
    May 2014

    Posted 08 May 2014 in reply to John Link to this post

    Hello again Vessy,

    I have done some more investigation here. I will try to give you some contextual information. We have a page with a popup control and a RadGrid. The popup is hidden until a button on the page is clicked. The popup control contains some Rad controls. Anyway, the problem may be reproduced reliably as follows.

    1. Click the button to make the popup appear.
    2. Click cancel to close the popup.
    3. Now click on the RadGrid. The exception is then thrown.

    Step 3 will cause the current page to redirect to another page. It seems that when the browser is forced to navigate away from the current page then the exception is thrown.

    I have found that the exception is only thrown when the popup has been displayed. So, I thought that it was caused by one of the Rad controls on the popup potentially. However, I have commented all the controls on the popup out and the exception is still being thrown if I follow steps 1 to 3 above.

    I have attached the Java Script stack trace as an image. Maybe that will be some use to you.

    Let me know what else I can provide. Actually, would it help if I provided all the markup for the page? If so, I would like to do so privately if possible. 

    Cheers,
    John.

  7. John
    John avatar
    31 posts
    Member since:
    May 2014

    Posted 08 May 2014 in reply to John Link to this post

    Here is the stack trace.
  8. Vessy
    Admin
    Vessy avatar
    1382 posts

    Posted 12 May 2014 Link to this post

    Hi John,

    Thank you for the provided explanations. Unfortunately they were not enough for us to reproduce and debug the issue on our side. We will need to examine the problematic markup at hand in order to be able to provide any further assistance.

    You can open a formal support ticket (where all provided information is private) and send us a simple fully runnable project we can reproduce the issue with.

    Looking forward to hearing from you,
    Vessy
    Telerik
     

    Check out the Telerik Platform - the only platform that combines a rich set of UI tools with powerful cloud services to develop web, hybrid and native mobile apps.

     
  9. John
    John avatar
    31 posts
    Member since:
    May 2014

    Posted 13 May 2014 in reply to Vessy Link to this post

    Hi Vessy,

    I will try assemble a minimal project and that reproduces the issue as soon as I can. Then I will open a support ticket.

    Cheers,
    John.
  10. Vessy
    Admin
    Vessy avatar
    1382 posts

    Posted 13 May 2014 Link to this post

    Hi John,

    Please take the needed time for isolating the issue and write back to us once you are done, so we could continue with the case investigation.

    Looking forward to hearing from you,
    Vessy
    Telerik
     

    Check out the Telerik Platform - the only platform that combines a rich set of UI tools with powerful cloud services to develop web, hybrid and native mobile apps.

     
  11. Tom
    Tom avatar
    1 posts
    Member since:
    Sep 2014

    Posted 23 Sep 2014 in reply to John Link to this post

    John, Were you able to get the issue of "Unable to get property 'length' of undefined or null reference" resolved?  We are experiencing the same problem. It appears to occur only when using IE and it appears to be a problem in the Telerik/Kendo javascript code.
  12. Tele
    Tele avatar
    5 posts
    Member since:
    Apr 2011

    Posted 27 Oct 2014 in reply to John Link to this post

    Same problem here :
    0x800a138f - JavaScript runtime error: Unable to get property 'length' of undefined or null reference

    for(u=null,t=this._events[i],n=0,e=t.length;n<e;n++) if(t[n].handler===r){u=t[n].browserHandler;break}this.removeEventListener?this.removeEventListener(i,u,!1)

    i="resize",
    t=this._events[i] // undefined
    t.length // JavaScript runtime error: 

    StackTrace is
    > Anonymous function [Telerik.Web.UI.WebResource.axd] Line 3 Script
      e.prototype.each [Telerik.Web.UI.WebResource.axd] Line 3 Script
      f._removeHandler [Telerik.Web.UI.WebResource.axd] Line 3 Script
      f.removeHandler [Telerik.Web.UI.WebResource.axd] Line 3 Script
      b.RadWindow.prototype._registerWindowResizeHandler [Telerik.Web.UI.WebResource.axd] Line 11605 Script
      b.RadWindow.prototype.disposeUI [Telerik.Web.UI.WebResource.axd] Line 11789 Script
      b.RadWindow.prototype.dispose [Telerik.Web.UI.WebResource.axd] Line 11781 Script
      f.prototype.dispose [Telerik.Web.UI.WebResource.axd] Line 3 Script
      f.prototype._unloadHandler [Telerik.Web.UI.WebResource.axd] Line 3 Script
      Anonymous function [Telerik.Web.UI.WebResource.axd] Line 3 Script
      n [Telerik.Web.UI.WebResource.axd] Line 3 Script














  13. Vessy
    Admin
    Vessy avatar
    1382 posts

    Posted 30 Oct 2014 Link to this post

    Hi Tele,

    I am afraid that as previously discussed with John we are not able to reproduce the problem on our side and, unfortunately the provided stack trace is not enough to determine what is causing the issue. It will be really helpful if you manage to isolate the exact configuration bringing the issue on your side and send it so we can examine it on our side.

    Regards,
    Vessy
    Telerik
     

    Check out the Telerik Platform - the only platform that combines a rich set of UI tools with powerful cloud services to develop web, hybrid and native mobile apps.

     
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