id	summary	reporter	owner	description	type	status	priority	milestone	component	version	severity	resolution	keywords	cc
19691	Cannot modify admin messages for /wp-admin/edit.php	mikeschinkel		"The admin console messages output on line `264` of WordPress 3.3's file `/wp-admin/edit.php` are not filterable. This causes problems when added row actions need to HTTP GET from to WordPress to modify a post and then display an appropriate message complete with a revert link ''(like the ""Trash"" link does.)''

An example use-case could be for a custom post type used for both quotes and invoices where a row action might be ''""Convert Quote to Invoice""'' where you'd want a message and link displayed at the top of the admin after similar to this:

- ''Quote #{$post_id} converted to Invoice. __Revert__''

Currently the only way to accomplish this is to pick hooks before and after the messages are output and use PHP's output buffering;  clearly not a ''""best practice""'' approach.

In order to address this I'm proposing an '''`'admin_messages'`''' filter hook to run just before the messages are output:

{{{
$messages = apply_filters( 'admin_messages', $messages );
}}}

However, since messages are output in numerous locations in the WordPress admin it seemed best to add the hook in every location where messages are output, which is what my patch does.  Thus a hook can look at `$pagenow` or `get_current_screen()` to decide it is needs to do anything.

Also while searching for places in the admin code that echo messages I found `$messages` are sometimes an array of HTML where the entire array is echoed and other times the $messages are an array with an index passed via `$_GET` and only one message will be displayed. For those cases I created another hook '''`'admin_message'`''' ''(note that this hook name is singular)'':

{{{
$message = apply_filters( 'admin_message', $message, $messages, $_GET['message'] );
}}}

I really only found a specific need for `/wp-admin/edit.php` today, but it seemed that it would be better for consistency if all messages were made hook filterable. That's why I created a larger patch when all my use-case needs is one new line.  

Looking forward to your feedback.
"	enhancement	new	normal	Awaiting Review	Administration	3.3	normal		dev-feedback has-patch 2nd-opinion	naomicbush mike@… mikeschinkel@…