Using the latest 6.3-dev without any patches and modifying some panel content (add/remove pane, change style...) I cannot save most of these changes.

If I select preview, an error occurs:
Fatal error: Call to undefined function panels_plugin_get_function() in /xxxxxxxx/sites/all/modules/panels/includes/display-edit.inc on line 678

Call Stack
#	Time	Memory	Function	Location
1	0.0002	126296	{main}( )	../index.php:0
2	0.2155	36027960	menu_execute_active_handler( )	../index.php:18
3	0.2375	39509168	call_user_func_array ( )	../menu.inc:348
4	0.2375	39509368	page_manager_edit_page_operation( )	../menu.inc:0
5	0.2422	39861632	page_manager_get_operation_content( )	../page_manager.admin.inc:399
6	0.2423	39861632	_page_manager_get_operation_content( )	../page_manager.admin.inc:777
7	0.2467	40606952	ctools_wizard_multistep_form( )	../page_manager.admin.inc:879
8	0.2521	41584408	ctools_build_form( )	../wizard.inc:94
9	0.2532	41663456	ctools_process_form( )	../form.inc:101
10	0.2635	42603568	form_execute_handlers( )	../form.inc:240
11	0.2635	42603568	panels_panel_context_edit_content_submit( )	../form.inc:769
12	0.2635	42603568	panels_edit_display_form_submit( )	../panel_context.inc:677
13	0.2636	42603904	panels_edit_display_settings_form_submit( )	../display-edit.inc:390

If I select Update, the Javascript disappears from the page, it switches to the nojs version, and the changes are reverted, eg. a removed pane is visible again.

Including plugins.inc in display-edit.inc did not successfully solve the issue. I cannot currently rule out the possibility that this error might be caused by other modules.

Comments

digi24’s picture

digi24 commented
Category: bug » support

After further testing, I have found out the following:
Using exactly the same code base on another configuration, panels etc. is working as expected.

On the defective system, any click on Update or Preview in the manage panel content tab, creates an error, irrespective whether I am creating a new panel or opening an existing configuration.

My question:
So, there is probably a problem with another module. Given the debug output above, I am kind of lost. I tried following the path back to ctools and dumping some variables, but I do not know what to look for.

Is there a suggested way to debug this issue?

merlinofchaos’s picture

merlinofchaos commented
Category: support » bug

It is possible you have a corner case that is simply failing to include a needed .inc file that is included when things happen a little differently. I'm away at Paris right now and cannot easily look at this, though, and it will be a couple of weeks before I have a chance, probably.

For now we're going to call this a bug report on the assumption that what we need is an include directive somewhere.

The actual call needed is probably panels_load_include('plugins') I think.

digi24’s picture

digi24 commented
Status: Active » Closed (fixed)

Thank you very much. Including plugins solved the error message, but did not solve the problem, other things appeared.

I have not found the exact cause yet, but I am close:
I did not keep in mind, although I knew better, that cck provides information to panels. The formatter (cck/includes/panels/content_types/content_field.inc) talks to other modules providing content fields. One or two of these modules in my case were not 100% ok, and basically caused the trouble.

Unfortunately I only received the error message, after playing with some includes at various places.

I will reopen when I find the exact cause.

Not to others, running into the same problem:
Check all modules that provide cck content fields.

mrfelton’s picture

mrfelton commented

Same problem for me. Disableing the tweetmeme module solved it for me. That module was also conflicting heavily with view... something todo with all the AHAH.

socialnicheguru’s picture

socialnicheguru commented

I get the same error and will try the solution outlined above- 'module hunt'

array(4) { ["type"]=> int(1) ["message"]=> string(55) "Call to undefined function panels_plugin_get_function()" ["file"]=> string(105) "/sites/all/modules/contrib/panels/includes/display-edit.inc" ["line"]=> int(762) }

cangeceiro’s picture

cangeceiro commented

I'm also experiencing this same error. I can confirm that disabling a custom module that adds its own panel panes stops the error, but I have 2 identical installations of the site, in one instance using panels 3.0 and do not get the error. On panels 3.2 I get the error. Currently I am debugging the custom module to see if anything has changed that just needs updating. but subscribing no less.

marcrobinsone’s picture

marcrobinsone commented

In my case, the Vertical Tabs and Form combo causes this error.

Simply disabling these modules gives me all the relief I need to edit my Panel pages.

Renee S’s picture

Renee S commented

@marcrobinsone: Form also interferes with Views - it tries to "Formify" every page with form elements, and the module doesn't discriminate between legit forms and other module input forms.

marcrobinsone’s picture

marcrobinsone commented

@renee: thanks for reconfirming this issue. Add Pathauto to the list.

I guess we should escalate this issue to the form module issue queue.

ronline’s picture

ronline commented

Not sure if the issue is caused by form . I'm having the same problem on my website without using http://drupal.org/project/form .

ronline’s picture

ronline commented
Version: 6.x-3.x-dev » 6.x-3.3
Status: Closed (fixed) » Active

Re openning the ticket.
Issue is showing in latest stable version 6.x-3.3.
The same error the same file :
Fatal error: Call to undefined function panels_plugin_get_function() in /home/htk/sd/eshop/www/sites/default/modules/panels/includes/display-edit.inc on line 764

merlinofchaos’s picture

merlinofchaos commented

Without some ability to reproduce this condition, which you have not provided, there is not a lot I can do.

marcrobinsone’s picture

marcrobinsone commented

@lamachine_fr:

Occasionally I encounter this error with modules that help (via UI) expose, alter, or edit the rendered form markup (such as form_alter, validation_api, and some more I now forgot). Some of these helper modules not just victimize Views or Panels, but other modules as well.

Unfortunately I haven't checked the watchdog logs as much as I'd like... Maybe there's an error log that might help you identify this occurrence on your end?

crutch’s picture

crutch commented

Not sure if related to this particular thread but I ended here when discovering what my issue was.

Experiencing odd behavior with disappearing panel content or double-adding of content when clicking update and save.

What changed?: Recently and unknowingly altered the way I saved panel changes by clicking the button "Update and Save" provided by ctools.

Solution: Follow the two step process of "Update" button first and then "Save".

I've never used "Preview" button because I normally click update, save and then view node to preview.

marcrobinsone’s picture

marcrobinsone commented

@crutch, I have to agree with you about the "Preview" button. I've also found it unhealthy, which is why I never use it. The most irking "strangeness" I had with the preview feature is that it deleted all my panel panes and gave me all sorts of errors when altering Panel pages. Recently, this doesn't happen probably due to an update to Panels/Ctools/Views (or possibly a module I installed that hooks with Panels).

Quite remarkably in my case, preview in Panel Nodes is much faster than preview in Panel Pages.

This may be because Panel Nodes leverage the Drupal node object, unlike Panels which uses its own way of dealing with content.

merlinofchaos’s picture

merlinofchaos commented
Status: Active » Postponed (maintainer needs more info)

About the time this bug report was filed, the Update and Save button was known to be buggy. As near as I can tell from discussion, this always happens due to other modules. Maybe there is something we can/should do about this, but I need concrete reproduction instructions to do it.

ronline’s picture

ronline commented
Title: Error when Updating/previewing panel content » Work around to save the panel

As mentioned by you@comment-3227604 and marcrobinsone@comment-2697364 the issue is in Update, Update and Save and Update and Preview buttons. The original “Save” button works fine the prob is that doesn't show up. I couldn't get work the cruch@comment-2694128 solution coz Update button gives me a WSOD.

My work around to display the working “Save” button:
Edit the panel and add an item.
Refresh the page with F5 button.
You'll see the message “You have unsaved changes to this page”. Working “Save” button is just under the message.
You press the “Save” and you are done, page will be saved.

hokuspokus’s picture

hokuspokus commented

+1 for the other modules interfering. I had the same problem with ckeditor combined with panel editing, removing panels from it's control using ckeditor visibility in the module controls allowed me to save edited panels again normally. Have to see if the latest update to ckeditor fixes this later.

pumpkinkid’s picture

pumpkinkid commented

From the Form Project Page...

In Drupal 6, Form module breaks Views configuration forms and likely other modules' forms.

This is a known issue with form caching/rebuilding in D6 and most likely, it cannot be resolved until D7. You may use this module for one-time form configurations, but make sure you DO NOT report bugs for other modules without making sure that you also encounter the bug after DISABLING Form module.

I have a feeling just enabling Form on D6 is enough to reproduce this issue...

pumpkinkid’s picture

pumpkinkid commented

By the way... it may be valuable to note that my workaround includes clearing the Drupal Cache before saving as mentioned on #17

Letharion’s picture

Letharion commented
Status: Postponed (maintainer needs more info) » Closed (cannot reproduce)

Because the issue queue has a great number of open issues, and there are few volunteers to tend them, I must prune old issues that are left untouched for a long time.
This issue has been marked "Postponed, needs info" for a long period, and is therefore closed. If this issue is still relevant to you, please feel free to re-open it.

iTiZZiMO’s picture

iTiZZiMO commented

Hello Everyone,

i get the same error:

"Fatal error: Call to undefined function panels_plugin_get_function() in sites/all/modules/panels/includes/display-edit.inc on line 305" when i add a variant to a page and try to save it.