I was actually looking for Mover Class. But I found in the direction you gave me is SmoothMover. Are they the same?
Not quite. The SmoothMover class gives the actor apparent movement that is not limited by the hardware (you cannot move between pixels; but if you track location coordinates more precisely, you can gain more control of the location of the actor). I do not think greenfoot has a Mover class in itself, but it does also come with an Animal class which has a speed field and a 'move' method. What would be best, in your case, depends on what functionality you are looking for in your actor. If interested in ideas, ask with details.
Thanks so much for your effort danpost. I watched this video on youtube and the tutor actually went to a greenfoot website to copy a Mover Class and pasted on his scenario but I cannot find that particular url. Please watch the video: https://www.youtube.com/watch?v=w7qSSPIKdFU and advice me.
Okay, the video had shown me the class documentation. It consists of 5 methods -- 2 of which are now included in the Actor class ('atWorldEdge()' and 'turn(int)'). The other 'turn()' method is just the same as 'turn(90)'. The last two methods are 'move()' and 'move(double)' where the first just calls the second using the 'double WALKING_SPEED' field. Since the coordinate location of the actor is not stored as double values, it does not effectively give the actor smooth movement. Also, if you had not noticed, the video was uploaded 6+ years ago -- using one of the earlier versions of greenfoot (probably greenfoot v2.0.1).
So, in my opinion, with what is given above, you are probably better not to use the class at all. Like I stated before:
What would be best, in your case, depends on what functionality you are looking for in your actor. If interested in ideas, ask with details.