I want to hide the parent theme in admin

Question

Could someone maybe explain to me how you can hide a parent theme in admin. I have been searching on the internet how to do this, but I can't seem to make it work. What is the correct code for it, and where do you put it?

I found this, but I don't understand it enough to make it work:

function kill_theme_wpse_188906($themes) {
  unset($themes['twentyten']);
  return $themes;
}
add_filter('wp_prepare_themes_for_js','kill_theme_wpse_188906');

kill_theme_wpse_188906 is that the parent theme name in this example? And code needs to be inserted in the functions.php of the child theme right?

I am sorry if this is a dumb question, but I am a bit stuck.

Answer 1

You should write the name of the theme as in the folder /wp-content/themes

For example, for hiding the default theme Twenty Fifteen you should write like this

function kill_themes($themes) {
  unset($themes['twentyfifteen']);
  return $themes;
}
add_filter('wp_prepare_themes_for_js','kill_themes');