java - How can I flick an object so it moves indefinitely with velocity depending on force of flick? -

i have circle on graph, , want able flick , have move indefinitely , wrap around screen goes. circle, or ball how coded it, view. right have circle can touch , drage, via code:

          //creates view ball            framelayout flview = (framelayout) v;            flview.setpaddingrelative(0, padding, 0, 0);             //creates new ball            ball = new ball(findviewbyid(r.id.main_view).getcontext(), x, y, 10,padding);              switch(event.getaction()){                     case motionevent.action_move:                            flview.removeallviews();                     flview.addview(ball);                      break;                   case motionevent.action_down:                             flview.removeallviews();                     flview.addview(ball);                      break;              }      

here's i'd do. i'd measure startposition (x,y) of ball, , time user first taps screen, ball, whatever. user moves finger across screen i'd calculate velocity given ball's current (x,y) , time. i'd calculate pixels / ms moving. once pick figure keep adding x,y velocity ball's position, , mod screen size it'll wrap.

// don't keep adding , removing ball view.   // add once on startup, can move ball's  // position when user clicks on screen. flview.addview(ball);  switch(event.getaction()){             case motionevent.action_move:                 ball.x = event.x;                 ball.y = event.y;                 int lastpositionx = ball.x                 int lastpositiony = ball.y                 long lasttime = system.currenttimemillis();                 ball.velocity.x = (lastpositionx - startpositionx) / (lasttime - starttime);                 ball.velocity.y = (lastpositiony - startpositiony) / (lasttime - starttime);                 break;             case motionevent.action_down:                        ball.x = event.x;                 ball.y = event.y;                 ball.velocity.x = 0.0;                 ball.velocity.y = 0.0;                 startpositionx = ball.x;                 startpositiony = ball.y;                 long starttime = system.currenttimemillis();                 break;        }  

i'm not sure code provided does, move section listener looks bad removed code think looked wrong. moves ball person touched. after you'll have figure out how animate scene. have this:

ball.x = (ball.velocity.x + ball.x) % screensize; ball.y = (ball.velocity.y + ball.y) % screensize;