Translation works with global variables, you just need to wait until the proper hook to call the translation functions. I haven’t looked at the code or documentation, but just by experimenting, the translations are loaded sometime before the after_setup_theme hook, but after the other hooks that fire before that.
That means that if you try to translate something on the plugins_loaded hook, you’re not going to get a translated result back.
As an example, in the following plugin, the first time $dash is “translated” in the main plugin file, it won’t be. It will always print “Dashboard” no matter what. Same thing on the plugins_loaded hook.
The fun part is in the after_setup_theme hook where the global $dash prints in English, but the newly translated text prints (in my case) “Escritorio”.
On the init hook, the global $dash prints the translated text. I added a callback to a closure to make sure that it was displaying the global $dash variable, and it was.
/**
* Plugin Name: StackExchange Sample
*/
namespace StackExchange\WordPress;
$dash = __( 'Dashboard ' );
printf( '<p>Main plugin file: %1$s</p>', $dash ); // Dashboard
class plugin {
public function plugins_loaded() {
\add_action( 'after_setup_theme', [ $this, 'after_setup_theme' ] );
\add_action( 'init', [ $this, 'init' ] );
echo '<h2>plugins_loaded</h2>';
global $dash;
printf( '<p>Global: %1$s</p>', $dash ); // Dashboard
$dash = __( 'Dashboard' );
printf( '<p>Local: %1$s</p>', $dash ); // Dashboard
}
public function after_setup_theme() {
echo '<h2>after_setup_theme</h2>';
global $dash;
printf( '<p>Global: %1$s</p>', $dash ); // Dashboard
$dash = __( 'Dashboard' );
printf( '<p>Local: %1$s</p>', $dash ); // Escritorio
}
public function init() {
echo '<h2>init</h2>';
global $dash;
printf( '<p>Global: %1$s</p>', $dash ); // Escritorio
$dash = __( 'Dashboard' );
printf( '<p>Local: %1$s</p>', $dash ); // Escritorio
}
}
\add_action( 'plugins_loaded', [ new plugin(), 'plugins_loaded' ] );
\add_action( 'init', function() {
global $dash;
printf( '<p>Global: %1$s</p>', $dash ); // Escritorio
}, 20 );
In summation: global variables with translated text do work, make sure you wait until after the after_setup_theme hook to translate your text, and don’t use global variables because it’ll just cause problems.