Customizable Media Uploader in WordPress admin area

function misha_include_myuploadscript() {
	/*
	 * I recommend to add additional conditions just to not to load the scipts on each page
	 * like:
	 * if ( !in_array('post-new.php','post.php') ) return;
	 */
	if ( ! did_action( 'wp_enqueue_media' ) ) {
		wp_enqueue_media();
	}
 
 	wp_enqueue_script( 'myuploadscript', get_stylesheet_directory_uri() . '/customscript.js', array('jquery'), null, false );
}
 
add_action( 'admin_enqueue_scripts', 'misha_include_myuploadscript' );

/*
 * @param string $name Name of option or name of post custom field.
 * @param string $value Optional Attachment ID
 * @return string HTML of the Upload Button
 */
function misha_image_uploader_field( $name, $value = '') {
	$image = ' button">Upload image';
	$image_size = 'full'; // it would be better to use thumbnail size here (150x150 or so)
	$display = 'none'; // display state ot the "Remove image" button
 
	if( $image_attributes = wp_get_attachment_image_src( $value, $image_size ) ) {
 
		// $image_attributes[0] - image URL
		// $image_attributes[1] - image width
		// $image_attributes[2] - image height
 
		$image = '"><img src="' . $image_attributes[0] . '" style="max-width:95%;display:block;" />';
		$display = 'inline-block';
 
	} 
 
	return '
	<div>
		<a href="#" class="misha_upload_image_button' . $image . '</a>
		<input type="hidden" name="' . $name . '" id="' . $name . '" value="' . $value . '" />
		<a href="#" class="misha_remove_image_button" style="display:inline-block;display:' . $display . '">Remove image</a>
	</div>';
}

/*
 * Add a meta box
 */
add_action( 'admin_menu', 'misha_meta_box_add' );
 
function misha_meta_box_add() {
	add_meta_box('mishadiv', // meta box ID
		'More settings', // meta box title
		'misha_print_box', // callback function that prints the meta box HTML 
		'post', // post type where to add it
		'normal', // priority
		'high' ); // position
}
 
/*
 * Meta Box HTML
 */
function misha_print_box( $post ) {
	$meta_key = 'second_featured_img';
	echo misha_image_uploader_field( $meta_key, get_post_meta($post->ID, $meta_key, true) );
}
 
/*
 * Save Meta Box data
 */
add_action('save_post', 'misha_save');
 
function misha_save( $post_id ) {
	if ( defined('DOING_AUTOSAVE') && DOING_AUTOSAVE ) 
		return $post_id;
 
	$meta_key = 'second_featured_img';
 
	update_post_meta( $post_id, $meta_key, $_POST[$meta_key] );
 
	// if you would like to attach the uploaded image to this post, uncomment the line:
	// wp_update_post( array( 'ID' => $_POST[$meta_key], 'post_parent' => $post_id ) );
 
	return $post_id;
}

add_action('admin_menu', 'misha_add_options_page');
 
function misha_add_options_page() {
	$page_slug = 'uplsettings';
	$option_name = 'header_img';
 
	if ( isset( $_GET['page'] ) && $_GET['page'] == $page_slug ) {
		if ( isset( $_REQUEST['action'] ) && 'save' == $_REQUEST['action'] ) {
			update_option( $option_name, $_REQUEST[ $option_name ] );
			header('Location: '. site_url() .'/wp-admin/options-general.php?page=' . $page_slug . '&saved=true');
			die;
		}
	}
	add_submenu_page('options-general.php','More settings','More settings (title)', 'edit_posts', $page_slug, 'misha_print_options_page');
}
 
function misha_print_options_page() {
 
	$option_name = 'header_img';
 
	if ( isset( $_REQUEST['saved'] ) ){
		echo '<div class="updated"><p>Saved.</p></div>';
	}
	echo '<div class="wrap"><form method="post">'
	. misha_image_uploader_field( $option_name, get_option( $option_name ) )
	. '<p class="submit">
		<input name="save" type="submit" class="button-primary" value="Save changes" />
		<input type="hidden" name="action" value="save" />
		</p></form></div>';
}

new trueMetaBox( array(
		'id'	=>	'misha', // metabox ID, this is also used as custom field prefix
		'name'	=>	'Metabox with the image upload button', // title
		'post_type'	=> array('page'), // post types here
		'priority'	=> 'high', // low | high | default
		'capability'=>	'edit_posts', // capabilities the user should have to edit this metabox
		'args'	=>	array(
 
			array(
				'id'		=> 'img',
				'label'		=> 'Image',
				'description'	=> 'The upload button description should be here.',
				'type'		=> 'image'
			)
 
		)
	)
);

new trueOptionspage( array(
	'slug'		=> 'general',
	'sections' 	=> array(
 		array(
			'id'	=> 'default',
			'fields'=> array(
				array(
					'id'		=> 'img1',
					'label'		=> 'Custom image in setting',
					'description'	=> 'Your custom description is here.',
					'type'		=> 'image'
				)
 			)
		) 
	)
));