Wong Kar-Wai grew and made his main films in Hong-Kong, which was not part of China (AKA People's Republic of China). I believe most of his actors spoke Cantone

Wong Kar-Wai grew and made his main films in Hong-Kong, which was not part of China (AKA People's Republic of China). I believe most of his actors spoke Cantonese, not Mandarin. Since these languages are mutually unintelligible, it's of little use to the OP which was learning the latter.