Changes for select_advanced:

- change folder name to `select2` only
- make it a child field of `select` so we can forget about how it save/get data
- make `placeholder` work

inc/fields/select-advanced.php

@@ -2,9 +2,12 @@
 // Prevent loading this file directly
 defined( 'ABSPATH' ) || exit;
 
+// Make sure "select" field is loaded
+require_once RWMB_FIELDS_DIR . 'select.php';
+
 if ( !class_exists( 'RWMB_Select_Advanced_Field' ) )
 {
-	class RWMB_Select_Advanced_Field
+	class RWMB_Select_Advanced_Field extends RWMB_Select_Field
 	{
 		/**
 		 * Enqueue scripts and styles
@@ -13,10 +16,11 @@ class RWMB_Select_Advanced_Field
 		 */
 		static function admin_enqueue_scripts()
 		{
-			wp_enqueue_style( 'select2', RWMB_CSS_URL . 'select2-css/select2.css', array(), '3.2' );
+			wp_enqueue_style( 'select2', RWMB_CSS_URL . 'select2/select2.css', array(), '3.2' );
 			wp_enqueue_style( 'rwmb-select-advanced', RWMB_CSS_URL . 'select-advanced.css', array(), RWMB_VER );
-			wp_register_script( 'select2',  RWMB_JS_URL . 'select2-js/select2.js', array(), '3.2', true );
-			wp_enqueue_script( 'select_advanced',  RWMB_JS_URL . 'select-advanced.js', array('select2'), RWMB_VER, true );
+
+			wp_register_script( 'select2', RWMB_JS_URL . 'select2/select2.min.js', array(), '3.2', true );
+			wp_enqueue_script( 'rwmb-select-advanced', RWMB_JS_URL . 'select-advanced.js', array( 'select2' ), RWMB_VER, true );
 		}
 
 		/**
@@ -31,12 +35,15 @@ static function admin_enqueue_scripts()
 		static function html( $html, $meta, $field )
 		{
 			$html = sprintf(
-				'<select class="rwmb-select-advanced" name="%s" id="%s"%s data-options ="%s">',
+				'<select class="rwmb-select-advanced" name="%s" id="%s"%s data-options="%s">',
 				$field['field_name'],
 				$field['id'],
 				$field['multiple'] ? ' multiple="multiple"' : '',
-				esc_attr( json_encode( $field['js_options'] ))
+				esc_attr( json_encode( $field['js_options'] ) )
 			);
+			if ( !empty( $field['js_options']['placeholder'] ) )
+				$html .= '<option></option>';
+
 			$option = '<option value="%s" %s>%s</option>';
 
 			foreach ( $field['options'] as $value => $label )
@@ -53,59 +60,6 @@ static function html( $html, $meta, $field )
 			return $html;
 		}
 
-		/**
-		 * Get meta value
-		 * If field is cloneable, value is saved as a single entry in DB
-		 * Otherwise value is saved as multiple entries (for backward compatibility)
-		 *
-		 * @see "save" method for better understanding
-		 *
-		 * TODO: A good way to ALWAYS save values in single entry in DB, while maintaining backward compatibility
-		 *
-		 * @param $meta
-		 * @param $post_id
-		 * @param $saved
-		 * @param $field
-		 *
-		 * @return array
-		 */
-		static function meta( $meta, $post_id, $saved, $field )
-		{
-			$single = $field['clone'] || !$field['multiple'];
-			$meta = get_post_meta( $post_id, $field['id'], $single );
-			$meta = ( !$saved && '' === $meta || array() === $meta ) ? $field['std'] : $meta;
-
-			$meta = array_map( 'esc_attr', (array) $meta );
-
-			return $meta;
-		}
-
-		/**
-		 * Save meta value
-		 * If field is cloneable, value is saved as a single entry in DB
-		 * Otherwise value is saved as multiple entries (for backward compatibility)
-		 *
-		 * TODO: A good way to ALWAYS save values in single entry in DB, while maintaining backward compatibility
-		 *
-		 * @param $new
-		 * @param $old
-		 * @param $post_id
-		 * @param $field
-		 */
-		static function save( $new, $old, $post_id, $field )
-		{
-			if ( !$field['clone'] )
-			{
-				RW_Meta_Box::save( $new, $old, $post_id, $field );
-				return;
-			}
-
-			if ( empty( $new ) )
-				delete_post_meta( $post_id, $field['id'] );
-			else
-				update_post_meta( $post_id, $field['id'], $new );
-		}
-
 		/**
 		 * Normalize parameters for field
 		 *
@@ -115,19 +69,18 @@ static function save( $new, $old, $post_id, $field )
 		 */
 		static function normalize_field( $field )
 		{
+			$field = parent::normalize_field( $field );
+
 			$field = wp_parse_args( $field, array(
 				'js_options' => array(),
 			) );
 
 			$field['js_options'] = wp_parse_args( $field['js_options'], array(
-				'allowClear' => true,
-				'width' => 'resolve',
-				'placeholder' => "Select a Value"
+				'allowClear'  => true,
+				'width'       => 'resolve',
+				'placeholder' => __( 'Select a value', 'rwmb' )
 			) );
-
-			$field['field_name'] = $field['id'];
-			if ( !$field['clone'] && $field['multiple'] )
-				$field['field_name'] .= '[]';
+
 			return $field;
 		}
 	}

js/select-advanced.js

@@ -1,20 +1,20 @@
 /**
- * Update date picker element
+ * Update select2
  * Used for static & dynamic added elements (when clone)
  */
 function rwmb_update_select_advanced()
 {
 	var $ = jQuery;
 
-	$( '.rwmb-select-advanced' ).each( function()
+	$( '.rwmb-select-advanced' ).each( function ()
 	{
 		var $this = $( this ),
 			options = $this.data( 'options' );
-		$this.select2(options);
+		$this.select2( options );
 	} );
 }
 
-jQuery( document ).ready( function()
+jQuery( document ).ready( function ()
 {
 	rwmb_update_select_advanced();
 } );