1. Johnny is a talented actor, and his acting skills have been recognized by the audience and the industry. Director Yi Tian may think that Johnny's image and style are very suitable for his role in movies or TV series, so he invited him to cooperate.
Johnny has a good reputation and extensive contacts in the entertainment circle, which may bring more resources and opportunities for the works directed by Yi Tian.
3. Director Yi Tian may be impressed by Johnny's previous cooperation and think that they have good tacit understanding and cooperation experience, so he hopes to cooperate again.
To sum up, director Tianyi has been looking for Johnny to cooperate, perhaps because Johnny's acting, image and style meet the requirements of his works, or because they have good cooperation experience and tacit understanding.