Register a menu - Error Header

Question

Could someone have the same error when im trying to register a menu?

function.php

function register_my_menu() {
  register_nav_menu('header-menu',__( 'Header Menu' ));
}
add_action( 'init', 'register_my_menu' );

error

function register_my_menu() { register_nav_menu('header-menu',__( 'Header Menu' )); } add_action( 'init', 'register_my_menu' ); Warning: Cannot modify header information - headers already sent by (output started at /home/milibyte/public_html/wp-content/themes/test/functions.php:4) in /home/milibyte/public_html/wp-admin/includes/misc.php on line 1126

GitHub

Regards!

Answer 1

<?php
function register_my_menu() {
    register_nav_menu( 'header-menu',__( 'Header Menu' ) );
}
add_action( 'after_setup_theme', 'register_my_menu' );

Answer 2

The error may display itself when there are:

• Blank lines at the top or bottom of a document
• Too many spaces before, in between or after the beginning PHP tags
• There are too many unneeded spaces or blank lines in a specific part of a document

Just to debug, try to do something like this.

function register_my_menu() { 
     //do nothing 
} 
add_action( 'init', 'register_my_menu' );

If you Google that issue you will get amazed by how many people have that just because of extra spaces or wrong things on the functions.php.

Answer 3

I believe you are running your action too soon.

Don't run it at 'init', use 'after_setup_theme' instead.

add_action( 'after_setup_theme', 'register_my_menu' );