display_id_add_columns.php

<?php
add_filter( 'manage_posts_columns', 'ws_cutom_columns_head', 20 );
add_action( 'manage_posts_custom_column',  'ws_cutom_columns_content', 10, 2 );
 
    function ws_cutom_columns_head( $columns ) {
 
        $columns['ws_post_id'] = 'ID';
 
        return $columns;
 
    }
 
    function ws_cutom_columns_content( $column_name, $id ) {
 
        if ( 'ws_post_id' == $column_name ) {
 
            echo $id;
 
        }
 
    } 
?>

display_id_add_hooks.php

<?php
// post types
    $post_types = get_post_types( array( 
            'public'    => true
        ) );
        foreach( $post_types as $post_type ) {
            add_action( 'manage_' . $post_type . '_posts_custom_column', array( $this, 'ws_cutom_columns_content' ), 10, 2 );
            add_filter( 'manage_' . $post_type . '_posts_columns', array( $this, 'ws_cutom_columns_head' ), 20 );        
        }
 
        //comments
        add_action( 'manage_comments_custom_column', array( $this, 'ws_cutom_columns_content' ), 10, 2 );
        add_filter( 'manage_edit-comments_columns', array( $this, 'ws_cutom_columns_head' ), 20 );
 
        // media
        add_action( 'manage_media_custom_column', array( $this, 'ws_cutom_columns_content' ), 10, 2 );
        add_filter( 'manage_media_columns', array( $this, 'ws_cutom_columns_head' ), 20 );
         
        //taxonomies
        $taxonomies = get_taxonomies();
 
        foreach ( $taxonomies as $taxonomy ) {
            add_action( 'manage_' . $taxonomy . '_custom_column', array( $this, 'alt_ws_cutom_columns_content' ), 10, 3 );
            add_filter( 'manage_edit-' . $taxonomy . '_columns', array( $this, 'ws_cutom_columns_head' ), 20 );         
        }
 
        //users     
        add_action( 'manage_users_custom_column', array( $this, 'alt_ws_cutom_columns_content' ), 10, 3 );
        add_filter( 'manage_users_columns', array( $this, 'ws_cutom_columns_head' ), 20 );
?>

display_id_column_width.php

<?php
add_action( 'admin_head', 'ws_add_css' );
function ws_add_css( $page ) {
        ?>
 
        <style type="text/css">
            #ws_post_id {
                width: 74px;
            }
        </style>
 
    <?php }?>

display_id_final.php

<?php
// post types
    $post_types = get_post_types( array( 
            'public'    => true
        ) );
        foreach( $post_types as $post_type ) {
            add_action( 'manage_' . $post_type . '_posts_custom_column', array( $this, 'ws_cutom_columns_content' ), 10, 2 );
            add_filter( 'manage_' . $post_type . '_posts_columns', array( $this, 'ws_cutom_columns_head' ), 20 );        
        }
 
        //comments
        add_action( 'manage_comments_custom_column', array( $this, 'ws_cutom_columns_content' ), 10, 2 );
        add_filter( 'manage_edit-comments_columns', array( $this, 'ws_cutom_columns_head' ), 20 );
 
        // media
        add_action( 'manage_media_custom_column', array( $this, 'ws_cutom_columns_content' ), 10, 2 );
        add_filter( 'manage_media_columns', array( $this, 'ws_cutom_columns_head' ), 20 );
         
        //taxonomies
        $taxonomies = get_taxonomies();
 
        foreach ( $taxonomies as $taxonomy ) {
            add_action( 'manage_' . $taxonomy . '_custom_column', array( $this, 'alt_ws_cutom_columns_content' ), 10, 3 );
            add_filter( 'manage_edit-' . $taxonomy . '_columns', array( $this, 'ws_cutom_columns_head' ), 20 );         
        }
 
        //users     
        add_action( 'manage_users_custom_column', array( $this, 'alt_ws_cutom_columns_content' ), 10, 3 );
        add_filter( 'manage_users_columns', array( $this, 'ws_cutom_columns_head' ), 20 );
 
 function ws_cutom_columns_head( $columns ) {
        $checkbox = array_slice( $columns , 0, 1 );
        $columns = array_slice( $columns , 1 );
 
        $new['ws_post_id'] = 'ID';
 
        $columns = array_merge( $checkbox, $new, $columns );
 
        return $columns;
    }
 
    function ws_cutom_columns_content( $column_name, $id ) {
 
        if ( 'ws_post_id' == $column_name ) {
 
            echo $id;
 
        }
 
function alt_ws_cutom_columns_content( $value, $column_name, $id ) {
 
        if ( 'ws_post_id' == $column_name ) {
 
            $value = $id;
 
        }
        return $value;
 
    }
 
add_action( 'admin_head', 'ws_add_css' );
function ws_add_css( $page ) {
        ?>
 
        <style type="text/css">
            #ws_post_id {
                width: 74px;
            }
        </style>
 
    <?php }
?>

display_id_to_front.php

<?php
function ws_cutom_columns_head( $columns ) {
        $checkbox = array_slice( $columns , 0, 1 );
        $columns = array_slice( $columns , 1 );
 
        $new['ws_post_id'] = 'ID';
 
        $columns = array_merge( $checkbox, $new, $columns );
 
        return $columns;
    }
?>