Move markers in google map v2 android

I am doing map clustering in Android Google maps v2. I just want to animate the marker from one geopoint to another. Is there a way to move a marker in Google maps v2?


Solution 1:

There's one example of moving marker in google map v2 demo app .. in the sample of the play library!!

I have looked into that!! here the code for moving an marker : -- >

    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);
                    }
                }
            }
        });
    }

Hope it help every one!!

Solution 2:

Proper way with ValueAnimator :

double[] startValues = new double[]{marker.getPosition().latitude, marker.getPosition().longitude};
double[] endValues = new double[]{destLatLng.latitude, destLatLng.longitude};
ValueAnimator latLngAnimator = ValueAnimator.ofObject(new DoubleArrayEvaluator(), startValues, endValues);
latLngAnimator.setDuration(600);
latLngAnimator.setInterpolator(new DecelerateInterpolator());
latLngAnimator.addUpdateListener(new ValueAnimator.AnimatorUpdateListener() {
    @Override
    public void onAnimationUpdate(ValueAnimator animation) {
        double[] animatedValue = (double[]) animation.getAnimatedValue();
        marker.setPosition(new LatLng(animatedValue[0], animatedValue[1]));
    }
});
latLngAnimator.start();

DoubleArrayEvaluator does not exist in android.animation package, there is my implementation :

import android.animation.TypeEvaluator;

/**
 * Inspired from {@link android.animation.FloatArrayEvaluator}
 * <p/>
 * This evaluator can be used to perform type interpolation between <code>double[]</code> values.
 * Each index into the array is treated as a separate value to interpolate. For example,
 * evaluating <code>{100, 200}</code> and <code>{300, 400}</code> will interpolate the value at
 * the first index between 100 and 300 and the value at the second index value between 200 and 400.
 */
public class DoubleArrayEvaluator implements TypeEvaluator<double[]> {

    private double[] mArray;

    /**
     * Create a DoubleArrayEvaluator that does not reuse the animated value. Care must be taken
     * when using this option because on every evaluation a new <code>double[]</code> will be
     * allocated.
     *
     * @see #DoubleArrayEvaluator(double[])
     */
    public DoubleArrayEvaluator() {
    }

    /**
     * Create a DoubleArrayEvaluator that reuses <code>reuseArray</code> for every evaluate() call.
     * Caution must be taken to ensure that the value returned from
     * {@link android.animation.ValueAnimator#getAnimatedValue()} is not cached, modified, or
     * used across threads. The value will be modified on each <code>evaluate()</code> call.
     *
     * @param reuseArray The array to modify and return from <code>evaluate</code>.
     */
    public DoubleArrayEvaluator(double[] reuseArray) {
        mArray = reuseArray;
    }

    /**
     * Interpolates the value at each index by the fraction. If
     * {@link #DoubleArrayEvaluator(double[])} was used to construct this object,
     * <code>reuseArray</code> will be returned, otherwise a new <code>double[]</code>
     * will be returned.
     *
     * @param fraction   The fraction from the starting to the ending values
     * @param startValue The start value.
     * @param endValue   The end value.
     * @return A <code>double[]</code> where each element is an interpolation between
     * the same index in startValue and endValue.
     */
    @Override
    public double[] evaluate(float fraction, double[] startValue, double[] endValue) {
        double[] array = mArray;
        if (array == null) {
            array = new double[startValue.length];
        }

        for (int i = 0; i < array.length; i++) {
            double start = startValue[i];
            double end = endValue[i];
            array[i] = start + (fraction * (end - start));
        }
        return array;
    }
}