javaandroidtimeelapsed

Measure elapsed time between two MotionEvents in Android


I'm new in Android programming so I am asking for your help in my problem. I am trying to measure in seconds/milliseconds the amount of time between a MouseEvent.ACTION_DOWN and MouseEvent.ACTION_UP.

@Override
public boolean onTouchEvent(MotionEvent event) {
    long start=0;
    if (event.getAction() == MotionEvent.ACTION_DOWN) {
        // manage down press
        start=System.nanoTime();//START
        System.out.println("START");
    }
    else if (event.getAction() == MotionEvent.ACTION_MOVE) {
        // manage move
        System.out.println(event.getRawX()+","+event.getRawY());
    }
    else {
        // manage up
        long finish=System.nanoTime()//FINISH
        long seconds = (finish-start) / 1000000000;//for seconds
        Toast.makeText(this, "FINISH, duration: "+seconds, Toast.LENGTH_SHORT).show();
        System.out.println("FINISH, duration: "+seconds);
    }
    return true;
}




Logcat:
03-19 04:04:27.140: I/System.out(4348): START
03-19 04:04:27.160: I/System.out(4348): 517.0,280.0
03-19 04:04:27.190: I/System.out(4348): 517.0,280.0
03-19 04:04:27.200: I/System.out(4348): 517.0,280.0
03-19 04:04:27.220: I/System.out(4348): 517.0,280.0
03-19 04:04:27.250: I/System.out(4348): 517.0,280.0
03-19 04:04:27.260: I/System.out(4348): 517.0,280.0
03-19 04:04:27.300: I/System.out(4348): 517.0,280.0
03-19 04:04:27.310: I/System.out(4348): 517.0,280.0
03-19 04:04:27.330: I/System.out(4348): FINISH, duration: 16545

My problem consist in fact that seconds variable doesn't show what I want, I even don't know if its measuring correctly.For the above example duration was 16545 (???!?!?) but it should have been between 1-3 seconds.What shall I do to measure correctly in seconds or milliseconds the time between two MotionEvents or what am I wrong in my example ? Thank you !


Solution

  • long startTime;
    public boolean onTouchEvent(MotionEvent event) {
    
        if (event.getAction() == MotionEvent.ACTION_DOWN) 
            startTime = System.nanoTime();    
    
        else if (event.getAction() == MotionEvent.ACTION_UP) {
            long elapseTime = System.nanoTime() - startTime;
            //do whatever u want with elapseTime now, its in nanoseconds
        }
    }