Following this tutorial, I am trying to create a custom Meta Box on my theme by adding following codes to the function.php file:
add_meta_box( 'my-meta-box-id', 'My First Meta Box', 'cd_meta_box_cb', 'post', 'normal', 'high' );
add_action( 'add_meta_boxes', 'cd_meta_box_add' );
function cd_meta_box_add()
{
add_meta_box( 'my-meta-box-id', 'My First Meta Box', 'cd_meta_box_cb', 'post', 'normal', 'high' );
}
function cd_meta_box_cb()
{
echo 'What you put here, show's up in the meta box';
}
but I am getting following error :
( ! ) Fatal error: Call to undefined function add_meta_box() in C:wampwwwTMPresswp-contentthemestwentytwelvecpt.php on line 94
Call Stack
# Time Memory Function Location
1 0.0012 865440 {main}( ) ..edit.php:0
2 0.0018 982824 require_once( 'C:wampwwwTMPresswp-adminadmin.php' ) ..edit.php:10
3 0.0021 1008744 require_once( 'C:wampwwwTMPresswp-load.php' ) ..admin.php:30
4 0.0023 1026872 require_once( 'C:wampwwwTMPresswp-config.php' ) ..wp-load.php:29
5 0.0029 1158248 require_once( 'C:wampwwwTMPresswp-settings.php' ) ..wp-config.php:90
6 0.3251 32951888 include( 'C:wampwwwTMPresswp-contentthemestwentytwelvefunctions.php' ) ..wp-settings.php:291
7 0.3255 32979176 include_once( 'C:wampwwwTMPresswp-contentthemestwentytwelvecpt.php' ) ..functions.php:2
Can you please let me know why this is happening? is there any better way to add a meta box containing a field and dropdown select box? I know there are some plugins out there for doing this but I really like to learn it on my own.
Try this
ps: you have some extra problematic lines, at the top of your code, that I removed, namely:
Update:
To add the metabox to your custom post type edit page, replace
'post'with'your-custom-post-type'in this line: