To create a message box for display in the admin panel, use either of the two following methods:
echo $this->info_message_box()->_( 'This is an info message box.' ); echo $this->error_message_box()->_( 'This is an %s message box.', 'error' );
After creating the message box, use the _() method to give it content and then return it to be echoed.
The _() method will translate the text and then try to run it through sprintf.