Adding a column in the media list page (no action yet)

wp-pdf-helper.php

@@ -1,21 +1,54 @@
 <?php
 /*
+ * vim: set ai sw=4 smarttab expandtab: tabstop=8 softtabstop=0
+ *
  * Plugin Name: WP PDF Helper
  * Description: Helps to print pages and posts as PDF  
  */
 
 // If this file is called directly, abort.
 if ( ! defined( 'WPINC' ) ) {
-	die;
+    die;
+}
+
+
+add_filter('manage_media_columns', 'add_media_column', 50, 2);
+function add_media_column($columns, $detached) {
+#    error_log('PHP: $columns: '.print_r($columns, true), 0);
+    $keys = array_keys($columns);
+    $columns_updated = [];
+    foreach ($keys as $key) {
+        $columns_updated[$key] = $columns[$key];
+        if ($key == 'parent') {
+            $columns_updated['wp-pdf-helper'] = 'Print';
+        }
+    }
+#    $actions['download'] = '<a href="' . wp_get_attachment_url($post->ID) . '">Download</a>';
+    return $columns_updated;
+}
+
+add_action('manage_media_custom_column', 'manage_custom_columns', 10, 2);
+
+function manage_custom_columns ($column_key, $post_id) {
+    if ($column_key == 'wp-pdf-helper') {
+        $checked = (get_post_meta($post_id, 'wpdfh.print', true) == '') ? '' : 'checked'; 
+        echo "<input type='checkbox' name='Print' value='always' $checked />";
+        error_log("PHP: \$column_key: $column_key, \$post_id: $post_id, \$is_printable: $is_printable.", 0);
+    }
+}
+
+add_action('admin_enqueue_scripts', 'wpdfh_enqueue_admin_scripts');
+function wpdfh_enqueue_admin_scripts() {
+    wp_enqueue_style( 'wpdfh-admin', plugin_dir_url( __FILE__ ) . 'assets/wp-pdf-helper-admin.css'  );
 }
 
 if ( ! array_key_exists('print', $_GET)) {
-	return;
+    return;
 }
 
-add_action('wp_enqueue_scripts', 'wpdfh_enqueue_scripts');
-function wpdfh_enqueue_scripts() {
-	wp_enqueue_style( 'wpdfh', plugin_dir_url( __FILE__ ) . 'assets/wp-pdf-helper.css'  );
+add_action('wp_enqueue_scripts', 'wpdfh_enqueue_print_scripts');
+function wpdfh_enqueue_print_scripts() {
+    wp_enqueue_style( 'wpdfh-print', plugin_dir_url( __FILE__ ) . 'assets/wp-pdf-helper-print.css'  );
 }
 
 #error_log("PHP: parse_url($url, PHP_URL_QUERY): ".print_r(parse_url($url, PHP_URL_QUERY), true), 0);
@@ -24,10 +57,10 @@ function wpdfh_enqueue_scripts() {
 add_filter( 'wpagpx_shortcode_parameters', 'filter_shortcode_parameters' );
 
 function filter_shortcode_parameters($parameters) {
-        $parameters['mheight'] = '200px';
-	$parameters['gheight'] = '150px';
-	$parameters['download'] = 'false';
-	$parameters['attachments'] = 'false';
-	return $parameters;
+    $parameters['mheight'] = '200px';
+    $parameters['gheight'] = '150px';
+    $parameters['download'] = 'false';
+    $parameters['attachments'] = 'false';
+    return $parameters;
 }