WP Admin List Tables hooks

test-list-tables.php

<?php
//////////////////
// Screens
//////////////////


// Posts
foreach ( array(
	'posts', 'pages', 'recipe_posts',
	'edit-post', 'edit-page', 'edit-recipe', 
) as $screen_id ) {
	add_filter( "manage_{$screen_id}_columns", 'register_test_column' );
	add_action( "manage_{$screen_id}_custom_column", 'display_test_column', 10, 2 );
}

// Media
foreach ( array(
	'media', 'upload'
) as $screen_id ) {
	add_filter( "manage_{$screen_id}_columns", 'register_test_column' );
	add_action( "manage_{$screen_id}_custom_column", 'display_test_column', 10, 2 );
}

// Terms
foreach ( array(
	'category', 'post_tag', 'color'
) as $taxonomy ) {
	add_filter( "manage_edit-{$taxonomy}_columns", 'register_test_column' );
	add_filter( "manage_{$taxonomy}_custom_column", 'render_test_column', 10, 3 );
}

// Comments
foreach ( array(
	'comments'
) as $screen_id ) {
	add_filter( "manage_edit-{$screen_id}_columns", 'register_test_column' );
	add_action( "manage_{$screen_id}_custom_column", 'display_test_column', 10, 2 );
}

// Users
foreach ( array(
	'users', 'users-network'
) as $screen_id ) {
	add_filter( "manage_{$screen_id}_columns", 'register_test_column' );
	add_filter( "manage_{$screen_id}_custom_column", 'render_test_column', 10, 3 );
}

// Plugins
foreach ( array(
	'plugins', 'plugins-network',
) as $screen_id ) {
	add_filter( "manage_{$screen_id}_columns", 'register_test_column' );
	add_action( "manage_{$screen_id}_custom_column", 'display_test_column', 10, 2 );
}

// Themes
foreach ( array(
	'themes', 'themes-network',
) as $screen_id ) {
	add_filter( "manage_{$screen_id}_columns", 'register_test_column' );
	add_action( "manage_{$screen_id}_custom_column", 'display_test_column', 10, 2 );
}

// Links
add_filter( "manage_link-manager_columns", 'register_test_column' );
add_action( "manage_link_custom_column", 'display_test_column', 10, 2 );


//////////////////
// Callbacks
//////////////////


function register_test_column( $columns ) {
	debug(current_filter());

	$columns['test'] = 'Test';

	return $columns;
}

function display_test_column( $column, $item_id ) {
	if ( 'test' != $column )
		return;

	debug(current_filter(), $item_id);
}

function render_test_column( $out, $column, $item_id ) {
	if ( 'test' != $column )
		return '';

	ob_start();
	debug(current_filter(), $item_id);
	return ob_get_clean();
}


//////////////////
// Setup
//////////////////


if ( !function_exists('debug') ) :
function debug() {
	$args = func_get_args();
	echo "<pre>\n";
	foreach ( $args as $arg ) {
		if ( is_object($arg) || is_array($arg) )
			print_r($arg);
		else
			var_dump($arg);
	}
	echo "</pre>\n";
}
endif;

function register_color_tax() {
	register_taxonomy( 'color', 'recipe', array('label' => 'Color') );
}
add_action( 'init', 'register_color_tax' );

function register_recipe_ptype() {
	register_post_type( 'recipe', array( 'public' => true ) );
}
add_action( 'init', 'register_recipe_ptype' );