Animate the rotation of the Marker in google map v2

Question

i am using google maps v2. i have a marker on map, this marker changes rotation every while. I want to animate the rotation of my maker to rotate smoothly. Can anyone help please

Answer 1

That's mine implementation of smooth marker movement with maker image rotation (when it's set to FLAT [important]). The marker is moved to the requested location smoothly plus it's rotated to the requested degree with a proper direction. For example, when moving from 5deg to 355deg it moves anticlockwise, when 355deg to 5deg it moves clockwise.

public void animateMarker(final Location location)
{
    if (myMarkerLOC != null) {
        final LatLngInterpolator latLngInterpolator = new LatLngInterpolator.LinearFixed();
        ValueAnimator valueAnimator = new ValueAnimator();
        final LatLng startPosition = myMarkerLOC.getPosition();
        final float startRotation = myMarkerLOC.getRotation();
        final float angle = 180 - Math.abs(Math.abs(startRotation - location.getBearing()) - 180);
        final float right = WhichWayToTurn(startRotation, location.getBearing());
        valueAnimator.addUpdateListener(new ValueAnimator.AnimatorUpdateListener()
        {
            @Override
            public void onAnimationUpdate(ValueAnimator animation)
            {
                try {
                    if (myMarkerLOC == null) // oops... destroying map during animation...
                    {
                        return;
                    }
                    float v = animation.getAnimatedFraction();
                    LatLng newPosition = latLngInterpolator.interpolate(v, startPosition, PositionUtil.toLatLng(location));
                    float rotation = startRotation + right * v * angle;
                    myMarkerLOC.setRotation((float) rotation);
                    myMarkerLOC.setPosition(newPosition);
                } catch (Exception ex) {
                    // I don't care atm..
                }
            }
        });
        valueAnimator.setFloatValues(0, 1);
        valueAnimator.setDuration(300);
        valueAnimator.start();
    }
}
private float WhichWayToTurn(float currentDirection, float targetDirection)
{
    float diff = targetDirection - currentDirection;
    if (Math.abs(diff) == 0)
    {
        return 0;
    }
    if(diff > 180)
    {
        return -1;
    }
    else
    {
        return 1;
    }
}
public interface LatLngInterpolator 
{
    public LatLng interpolate(float fraction, LatLng a, LatLng b);

    public class Linear implements LatLngInterpolator 
    {
        @Override
        public LatLng interpolate(float fraction, LatLng a, LatLng b) 
        {
            double lat = (b.latitude - a.latitude) * fraction + a.latitude;
            double lng = (b.longitude - a.longitude) * fraction + a.longitude;
            return new LatLng(lat, lng);
        }
    }
    public class LinearFixed implements LatLngInterpolator 
    {
        @Override
        public LatLng interpolate(float fraction, LatLng a, LatLng b) {
            double lat = (b.latitude - a.latitude) * fraction + a.latitude;
            double lngDelta = b.longitude - a.longitude;
            // Take the shortest path across the 180th meridian.
            if (Math.abs(lngDelta) > 180) {
                lngDelta -= Math.signum(lngDelta) * 360;
            }
            double lng = lngDelta * fraction + a.longitude;
            return new LatLng(lat, lng);
        }
    }
}

Missing implementation of "toLatLong" method:

 public static LatLng toLatLng(final Location location)
 {
    return new LatLng(location.getLatitude(), location.getLongitude());
 }

I hope that helps.