Media Uploader Wordpress

uploader.js

jQuery(document).ready(function(){
var _rtp_media = true,
    _orig_send_attachment = wp.media.editor.send.attachment;

    jQuery('.rtp-media-uploader').click(function () {

        var button = jQuery(this),
        textbox_id = jQuery(this).attr('data-id');

        _rtp_media = true;
        
        wp.media.editor.send.attachment = function (props, attachment) {
        if ( _rtp_media && ( attachment.mime === 'application/pdf' ) ) {
            jQuery( '#'+ textbox_id ).val( attachment.id );
                button.next().show();
        } else {
            alert('Please select a valid PDF file');
                return false;
            }
        }
        wp.media.editor.open(button);
        return false;
    });

    jQuery('.add_media').on('click', function(){
        _rtp_media = false;
    });
});