trazar - Cómo animar marcador en el mapa de Android api V2?

tipos de mapas android studio

Question

Quiero implementar una transición suave para emular el marcador de automóvil que se mueve en el mapa.

¿Es posible animar marcador en el mapa de Android api v2?

Answer 1

Acabo de implementar una versión, prueba esto

public class MarkerAnimation {
static GoogleMap map;
ArrayList<LatLng> _trips = new ArrayList<>() ;
Marker _marker;
LatLngInterpolator _latLngInterpolator = new LatLngInterpolator.Spherical();
public void animateLine(ArrayList<LatLng> Trips,GoogleMap map,Marker marker,Context current){
_trips.addAll(Trips);
_marker = marker;
animateMarker();
}
public void animateMarker() {
TypeEvaluator<LatLng> typeEvaluator = new TypeEvaluator<LatLng>() {
@Override
public LatLng evaluate(float fraction, LatLng startValue, LatLng endValue) {
return _latLngInterpolator.interpolate(fraction, startValue, endValue);
}
};
Property<Marker, LatLng> property = Property.of(Marker.class, LatLng.class, "position");
ObjectAnimator animator = ObjectAnimator.ofObject(_marker, property, typeEvaluator, _trips.get(0));
//ObjectAnimator animator = ObjectAnimator.o(view, "alpha", 0.0f);
animator.addListener(new Animator.AnimatorListener() {
@Override
public void onAnimationCancel(Animator animation) {
// animDrawable.stop();
}
@Override
public void onAnimationRepeat(Animator animation) {
// animDrawable.stop();
}
@Override
public void onAnimationStart(Animator animation) {
// animDrawable.stop();
}
@Override
public void onAnimationEnd(Animator animation) {
// animDrawable.stop();
if (_trips.size() > 1) {
_trips.remove(0);
animateMarker();
}
}
});
animator.setDuration(300);
animator.start();
}

La clase LatLngInterpolator está escrita previamente por chicos de Google, que puedes usar de la siguiente manera:

public interface LatLngInterpolator {
public LatLng interpolate(float fraction, LatLng a, LatLng b);
public class Spherical implements LatLngInterpolator {
@Override
public LatLng interpolate(float fraction, LatLng from, LatLng to) {
// http://en.wikipedia.org/wiki/Slerp
double fromLat = toRadians(from.latitude);
double fromLng = toRadians(from.longitude);
double toLat = toRadians(to.latitude);
double toLng = toRadians(to.longitude);
double cosFromLat = cos(fromLat);
double cosToLat = cos(toLat);
// Computes Spherical interpolation coefficients.
double angle = computeAngleBetween(fromLat, fromLng, toLat, toLng);
double sinAngle = sin(angle);
if (sinAngle < 1E-6) {
return from;
}
double a = sin((1 - fraction) * angle) / sinAngle;
double b = sin(fraction * angle) / sinAngle;
// Converts from polar to vector and interpolate.
double x = a * cosFromLat * cos(fromLng) + b * cosToLat * cos(toLng);
double y = a * cosFromLat * sin(fromLng) + b * cosToLat * sin(toLng);
double z = a * sin(fromLat) + b * sin(toLat);
// Converts interpolated vector back to polar.
double lat = atan2(z, sqrt(x * x + y * y));
double lng = atan2(y, x);
return new LatLng(toDegrees(lat), toDegrees(lng));
}
private double computeAngleBetween(double fromLat, double fromLng, double toLat, double toLng) {
// Haversine''s formula
double dLat = fromLat - toLat;
double dLng = fromLng - toLng;
return 2 * asin(sqrt(pow(sin(dLat / 2), 2) +
cos(fromLat) * cos(toLat) * pow(sin(dLng / 2), 2)));
}
}
}

A continuación, crea una instancia de un objeto de la clase MarkerAnimation y llama al método de esta manera:

 MarkerAnimation.animateLine(TripPoints,map,MovingMarker,context);

Answer 2

Ninguna de las versiones provistas me funcionó, así que implementé mi solución personalizada. Proporciona ambos - ubicación y animación de rotación.

/**
* Method to animate marker to destination location
* @param destination destination location (must contain bearing attribute, to ensure
* marker rotation will work correctly)
* @param marker marker to be animated
*/
public static void animateMarker(Location destination, Marker marker) {
if (marker != null) {
LatLng startPosition = marker.getPosition();
LatLng endPosition = new LatLng(destination.getLatitude(), destination.getLongitude());
float startRotation = marker.getRotation();
LatLngInterpolator latLngInterpolator = new LatLngInterpolator.LinearFixed();
ValueAnimator valueAnimator = ValueAnimator.ofFloat(0, 1);
valueAnimator.setDuration(1000); // duration 1 second
valueAnimator.setInterpolator(new LinearInterpolator());
valueAnimator.addUpdateListener(new ValueAnimator.AnimatorUpdateListener() {
@Override public void onAnimationUpdate(ValueAnimator animation) {
try {
float v = animation.getAnimatedFraction();
LatLng newPosition = latLngInterpolator.interpolate(v, startPosition, endPosition);
marker.setPosition(newPosition);
marker.setRotation(computeRotation(v, startRotation, destination.getBearing()));
} catch (Exception ex) {
// I don''t care atm..
}
}
});
valueAnimator.start();
}
}

Cálculo de rotación para una fracción de animación específica. El marcador se gira en una dirección que está más cerca de la rotación de inicio a fin:

private static float computeRotation(float fraction, float start, float end) {
float normalizeEnd = end - start; // rotate start to 0
float normalizedEndAbs = (normalizeEnd + 360) % 360;
float direction = (normalizedEndAbs > 180) ? -1 : 1; // -1 = anticlockwise, 1 = clockwise
float rotation;
if (direction > 0) {
rotation = normalizedEndAbs;
} else {
rotation = normalizedEndAbs - 360;
}
float result = fraction * rotation + start;
return (result + 360) % 360;
}

Y finalmente, LatLngInterpolator de Google:

private interface LatLngInterpolator {
LatLng interpolate(float fraction, LatLng a, LatLng b);
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);
}
}
}

Answer 3

Pruebe el siguiente código para animar el marcador en Google Map V2. Debe usar la clase Interpolator para aplicar la animación en el Marker y manejarla en el Handler para la animación de la siguiente manera:

 public void animateMarker(final Marker marker, final LatLng toPosition,
final boolean hideMarker) {
final Handler handler = new Handler();
final long start = SystemClock.uptimeMillis();
Projection proj = mGoogleMapObject.getProjection();
Point startPoint = proj.toScreenLocation(marker.getPosition());
final LatLng startLatLng = proj.fromScreenLocation(startPoint);
final long duration = 500;
final Interpolator interpolator = new LinearInterpolator();
handler.post(new Runnable() {
@Override
public void run() {
long elapsed = SystemClock.uptimeMillis() - start;
float t = interpolator.getInterpolation((float) elapsed
/ duration);
double lng = t * toPosition.longitude + (1 - t)
* startLatLng.longitude;
double lat = t * toPosition.latitude + (1 - t)
* startLatLng.latitude;
marker.setPosition(new LatLng(lat, lng));
if (t < 1.0) {
// Post again 16ms later.
handler.postDelayed(this, 16);
} else {
if (hideMarker) {
marker.setVisible(false);
} else {
marker.setVisible(true);
}
}
}
});
}