Recognising a screen size change

This is called responsive design and has nothing to do with WordPress, it is an extension rule to media queries (@media) in CSS3. CSS is a browser/client side language which can determine window sizes and browser types, this is what is used to determine how a website should look at a specific window size or … Read more

get_current_screen() inside add_action(‘admin_menu’)

I don’t know exactly what you are trying to accomplish but you seem to be dealing with meta boxes. If so there are a number of meta box specific hooks. do_action(‘add_meta_boxes’, $post_type, $post); do_action(‘add_meta_boxes_’ . $post_type, $post); do_action(‘do_meta_boxes’, $post_type, ‘normal’, $post); do_action(‘do_meta_boxes’, $post_type, ‘advanced’, $post); do_action(‘do_meta_boxes’, $post_type, ‘side’, $post); http://core.trac.wordpress.org/browser/tags/3.5.1/wp-admin/edit-form-advanced.php#L165 As well as the admin_head* … Read more

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