Will this be an infinite scroller (repeating or no scrolling background image)? or, will it be a limited scroller with a repeating or no scrolling background image? or, will it be a scroller limited to the size of an image used for the background? Will it scroll horizontally, vertically, or both ways (universally)? Is it a gridded world or does it use pixel sized cells (what is the 'super' call statement in your world class constructor)? Will the actors be using a smooth moving engine or not? There are multiple scrolling engines that are available on the site; however, answering these question will help in determining which ones may be suitable in your case. You can then either use it directly in your project (if it is provided as a support class) or you can learn how to construct one yourself by looking over to understand the code and creating one yourself (or try to mimic the code in your project).

Please answer the questions I provided above. I am not familiar with android games.