android - The difference of using MotionEvent.getAction() method -


what difference between 2 approaches below? 

 int action1 = event.getaction() & motionevent.action_mask;   int action2 = event.getaction();

the action_mask used separate actual action , pointer identifier (e.g. first finger touched, second finger touched, etc.) first 8 bits of value returned in getaction() actual action part, , when bitwise-and action mask (= 11111111 = 255 = 0xff), left action , none of pointer information.

keep in mind here & used arithmetic operator (bitwise) , not logical operator (single & valid logical operator in java, &&).`


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