public enum Font {
    REGULAR("Roboto-Regular"),
    MEDIUM("Roboto-Medium"),
    LIGHT("Roboto-Light"),
    PT_SANS_BOLD("PTS75F");

    private String filename;

    Font(String filename) {
        this.filename = filename;
    }

    public String getFilename() {
        return filename;
    }
}

//AND:
public class Typefaces {
    // <...>

    public static Typeface getByFont(Font font) {
        return getByName(MainApplication.getInstance(), font.getFilename());
    }
}

//USE:
playGame.setTypeface(Typefaces.getByFont(Font.REGULAR));