how to change the color RatingBar depending on the number of stars?

RatingBar ratingBar = (RatingBar) findViewById(R.id.ratingBar);
LayerDrawable stars = (LayerDrawable) ratingBar.getProgressDrawable();
stars.getDrawable(2).setColorFilter(Color.YELLOW, PorterDuff.Mode.SRC_ATOP);

OR

LayerDrawable stars = (LayerDrawable) ratingBar.getProgressDrawable();
        stars.getDrawable(2).setColorFilter(getResources().getColor(R.color.starFullySelected), PorterDuff.Mode.SRC_ATOP);
        stars.getDrawable(1).setColorFilter(getResources().getColor(R.color.starPartiallySelected), PorterDuff.Mode.SRC_ATOP);
        stars.getDrawable(0).setColorFilter(getResources().getColor(R.color.starNotSelected), PorterDuff.Mode.SRC_ATOP);

You can do this on

ratingBar.setOnRatingBarChangeListener(new OnRatingBarChangeListener(){

        @Override
        public void onRatingChanged(RatingBar ratingBar, float rating,
                boolean fromUser) {
            // This event is fired when rating is changed   
        }    
    }); 

From your code

 @Override
 public View getItemView(int section, int position, View convertView, ViewGroup parent) {
     LinearLayout layout;
     if (convertView == null) {
         LayoutInflater inflator = (LayoutInflater) parent.getContext().getSystemService(Context.LAYOUT_INFLATER_SERVICE);
         layout = (LinearLayout) inflator.inflate(R.layout.item_survey, null);
     } else {
         layout = (LinearLayout) convertView;
     }
     ((TextView) layout.findViewById(R.id.questionSurvey)).setText(surveyBeans.get(section).get(position).getQuestion());

     RatingBar ratingBar = ((RatingBar) layout.findViewById(R.id.ratingBar));
     ratingBar.setProgress(Integer.parseInt(surveyBeans.get(section).get(position).getRate()));

     if (ratingBar.getRating() == 2f) {
         //change color of two stars
     } else if (ratingBar.getRating() == 3f) {
         //change color of three stars
     }

     LayerDrawable stars = (LayerDrawable) ratingBar.getProgressDrawable();
     stars.getDrawable(2).setColorFilter(Color.YELLOW, PorterDuff.Mode.SRC_ATOP);
     stars.getDrawable(1).setColorFilter(Color.RED, PorterDuff.Mode.SRC_ATOP);
     ((TextView) layout.findViewById(R.id.commentSurvey)).setText(surveyBeans.get(section).get(position).getComment());

     return layout;
 }