Mohamed Abdelaziz wrote: Hello All,

I've found this issue while I'm editing some K2 items, after upgrading to Joomla 3.6.4
After some debugging on my personal website, I fixed this issue by hacking the file /administrator/components/com_k2/views/item/view.html.php
I replaced this statement:

FilterOutput::objectHTMLSafe($item, ENT_QUOTES, array(
			'video',
			'params',
			'plugins'
		));

With this one:

FilterOutput::objectHTMLSafe($item, ENT_QUOTES, array(
			'video',
			'params',
			'plugins',
                        'metadata'
		));

You can give it a try, may be it fix your issue.

Thank you, This resolved the issue for me as well. Joomla 3.6.5 / K2 v2.6.9

Cleaning the metadata is the only thing that worked for me - quick DIY post here:
goo.gl/vmaf80

-Alan

Nice one Alan.

I tried running your query like this [note my database prefix is 'jml3_']

SELECT * FROM `jml3_k2_items` SET `metadata` = 'robots=author=' WHERE `metadata` = '{"robots":"","author":"","rights":"","xreference":""}'

but I got the following message:

#1064 - You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the right syntax to use near 'SET `metadata` = 'robots=author=' WHERE `metadata` = '{"robots":"","author":"","' at line 1


I tried this query as suggested by someone else on the first page of this forum:

UPDATE `jml3_k2_items` SET `metadata` = ''

This one went through but in the SQL query page, but in Joomla in K2, the error message when opening any item didn't dissapear.

Finally, I tried changing the view.html.php file as suggested by Mohamed Abdelaziz on the first page, and that did work in removing the error message in K2 and allowing me to see my items. However, I fear that perhaps I might not be able to use metadata in my K2 items anymore by carrying out his solution. So I was wondering Concerto Designs LLC if you know why I'm getting this error message in the SQL query page when running your query with the correct database prefix?

Thanks!

My solution:
Step 1: Edit "(JOOMLA_PATH)/libraries/vendor/joomla/registry/src/Registry.php"
Step 2:
In line 366 replace:
$obj = $handler->stringToObject($data, $options);
to
$obj_count = json_decode($data);
if(count($obj_count) > 0) {
$obj = $handler->stringToObject($data, $options);
} else {
$obj = $obj_count;
}

And everything is back to normal!

Keep in mind that this is a core hack, which will be lost when you update.

Geo Ce wrote: My solution:
Step 1: Edit "(JOOMLA_PATH)/libraries/vendor/joomla/registry/src/Registry.php"
Step 2:
In line 366 replace:
$obj = $handler->stringToObject($data, $options);
to
$obj_count = json_decode($data);
if(count($obj_count) > 0) {
$obj = $handler->stringToObject($data, $options);
} else {
$obj = $obj_count;
}

And everything is back to normal!

Thank you Geo Ce... it managed to overcome my problem

Thank you very much
greetings from me , I hope you succeed

With K2 2.8 the error with the decoding still exists. Why does no fix has been integrated in the newest version?

This is not directly related to K2.
Some items might have been saved or imported incorrectly.
We cannot alter existing items.

This is not directly related to K2.
Some items might have been saved or imported incorrectly.
We cannot alter existing items.

Using Joomla 3.75, PHP7.0 and new install of K2 v2.8, after importing Joomla Content.

When accessing the imported content results in 0 Error decoding JSON data: syntax Error.
Note: The error did not occur until after the installation of K2.

One explanation of the issue is:
The Issue
Joomla stores rules and parameters in the database in JSON format. Previously, if that data was invalid JSON it would silently fail and the site would continue working.

In the 3.6.3 update, the validation of the syntax was improved, so issues that would previously go unnoticed now result in an error page with the aforementioned error message.
Known Causes

JBLibrary plugin - Causes errors on the frontend of the site, fixed in version 2.1.7
Jupgrade - Sites migrated from Joomla 1.5 using this extension.
Many other 3rd party extensions and core extensions have been mentioned.

How to Fix

Sites that have been migrated using Jupgrade may have empty parameter fields set as {""} which should either be {} or {"":""} to be valid syntax. This may be the same with other 3rd party extensions added to any site.

This is the easiest issue to fix and can be done with a simple search and replace on the database.
reference:
www.robertwent.com/blog/fixing-json-data-errors-after-updating-to-joomla-3-6-3/