Make Slingshot Animated

Great Idea, but we need a better way. now it looks slow and unnatural.
EDIT: i think if we would use this:

// at the top
const int FPS = 35;
        private int DURATION;
        private int RUN_LENGTH; // total number of frames
        private int current_frame = 1;

//in the page_left
if (current_position < 0) {

                //copied from the old slingshot's effect on category switching.
                this.DURATION = 150; // just copied from the old one, not sure if it's right.
                Timeout.add (((int)(1000/this.FPS)), () => {

                    if (this.current_frame >= this.RUN_LENGTH) {
        current_frame = 1;
     return false; // stop animation
                    }

                    view_manager.move (grid_view, current_position + val, 0);
                    this.current_frame++;
                    return true;

                });
            }

        }

it would give a nicer effect. I'm not sure if it works and it still needs much tweaking. I couldn't try it cause i have some building problems (i can change whatever i want in the code, but there is no difference). it would be nice if animations like slide, zoom etc. would be in granite! ~timschoen123