# Failed to mount: '4.1' Error

asked 2011-03-06 04:08:40 +0800

deepak09
3 1

"Failed to mount: '4.1' is null or not an object" error comes when i load a zul, this error is frequent in zk version 5.0.6.
Can you help me with this....

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answered 2011-03-06 07:17:54 +0800

perfomance
51

I am facing the same issue it will be great if someone can provide the solution for it.Is it any of the bug introduced by 5.0.6?

answered 2011-03-08 20:26:30 +0800

ashishd
1972 6

Hi deepak09 & performance
could anyone of you provide a smaple that would reproduce this issue? Also if possible try using the latest freshly to see if the error is still occurring. What ZK editions are you using CE/PE or EE? Is this error specific to any browser or it is consistent for all browsers?

answered 2011-03-31 20:04:39 +0800

darius
279 3

We're getting a similar error, that says "Failed to mount: 'length' is null or not an object"
It is tough to reproduce this as a simple ZUL, since it involves a few Java classes calling each other and referencing each other.

My question is: Is there some way to track down the approximate area (e.g. the particular component) causing the error, so that we can debug it faster?

answered 2011-04-03 01:11:39 +0800

perfomance
51

Hi,
While debugging i found that this error comes when component is not mounted and something is trying to access that component.
But one good think about this error :) was majority of times it does not stop the flow of the application or site.So one way around
is to catch the error and don''t do anything :)Not a proper solution but a way around for critical situation for emergency.in zk.jar mount.js,mount.src contains the function in which catch block is having code for failed to mount error.if we comment that line then message for error won't come.
if anybody got proper solution please share it

answered 2011-04-07 11:27:07 +0800

twiegand
1807 3

We are starting to see this in ZK 5.0.6 EE as well now. Just now I got this: "Failed to mount: this.$n() is undefined" Unfortunately, I cannot seem to spot a pattern to reproduce it. Also, it seems random in whether or not it stops the flow of our application(s). The sad part of this is that I cannot upgrade my production customers to 5.0.6 while this is going on. It seems we'll have to rewrite some code - we were trying to take advantage of new 5.0.6 functionality. Now I simply can't afford to take the risk. If someone finds a fix, I'd sure appreciate the insight. answered 2011-04-07 21:25:20 +0800 ashishd 1972 6 Please post this bug to the tracker with a sample code to reproduce this issue and also mention your environment details such as web server,browsers and their version, ZK version/editions etc. answered 2011-04-08 12:13:01 +0800 twiegand 1807 3 @ashishd, If I can find a way to reproduce the error with any regularity, I will be happy to post a bug in the tracker. answered 2011-06-17 07:57:50 +0800 darius 279 3 In our case, we found that the problem is related to the unofficial Selectbox component (http://blog.zkoss.org/index.php/2010/12/21/a-lightweight-dropdown-list-selectbox/) It only happens when this component is empty. I think it might be when some code mistakenly tries to set the selectedIndex while it is empty. answered 2012-06-08 09:56:25 +0800 ommpavan 231 I have a combo box with different values .I wrote a on Select event for this. In on Select event i am filling two list boxes using item render .When i am changing combo box values .I am getting the same error : "Failed to mount: this.$n() is undefined" .After tracing my code i am getting on filling list box values .Code is Executing with out any error but This error message is coming .The confusion is I am not always getting error by doing same action .Unable to find in which condition it is coming .Please let me know why error message coming and fix for this

answered 2012-06-08 10:14:37 +0800

ashishd
1972 6

hi ommpavan,
Any sample to reproduce?

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Asked: 2011-03-06 04:08:40 +0800

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Last updated: Jun 08 '12

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