Show Meta Box if a specific page template is used (jQuery)

Using this code you can show WordPress meta box for a specific template selected.

To do this add this code in to your themes function.php file

<?php
add_action( 'admin_head-post.php', 'metabox_switcher' ); 
add_action( 'admin_head-post-new.php', 'metabox_switcher' ); 

function metabox_switcher( $post ){ 

        #Locate the ID of your metabox with Developer tools 
        $metabox_selector_id = 'about-banner-image-meta'; 
        echo ' 
            <style type="text/css"> 
                /* Hide your metabox so there is no latency flash of your metabox before being hidden */ 
                #'.$metabox_selector_id.'{display:none;} 
            </style> 
            <script type="text/javascript"> 
                jQuery(document).ready(function($){ 

                    //You can find this in the value of the Page Template dropdown 
                    var templateName = 'template-about.php'; 

                    //Page template in the publishing options 
                    var currentTemplate = $('#page_template'); 

                    //Identify your metabox 
                    var metabox = $('#'.$metabox_selector_id.''); 

                    //On DOM ready, check if your page template is selected 
                    if(currentTemplate.val() === templateName){ 
                        metabox.show(); 
                    } 

                    //Bind a change event to make sure we show or hide the metabox based on user selection of a template 
                    currentTemplate.change(function(e){ 
                        if(currentTemplate.val() === templateName){ 
                            metabox.show(); 
                        } 
                        else{ 
                            //You should clear out all metabox values here; 
                            metabox.hide(); 
                        } 
                    }); 
                }); 
            </script> 
        '; 
}
?>