Image animation on Android -

i want image on android screen appear smaller when user touches down on , original size when user releases it. want animation smooth , want utilize minimum computing resources. how can best implemented?

try code

          @override             public boolean ontouch(view v, motionevent event) {                 switch (event.getaction()) {                  case motionevent.action_down:                    // here when touch                 break;                  case motionevent.action_up:                    // here when touch release                      break;                 }                  return true;             } 

for animation try animation-source_code