Develop Reference

Marker is not moving along to path with proper rotation

I have to draw a marker and a path on map; and I want to move the marker to the path, along with rotating it. My marker is moving, but not along the path. Here is my code:
Marker animation method
public void animateMarker(final int position, final LatLng startPosition, final LatLng toPosition,
final boolean hideMarker) {
Location source = new Location(LocationManager.GPS_PROVIDER);
source.setLatitude(sourceLat);
source.setLongitude(sourceLon);
Location dest = new Location(LocationManager.GPS_PROVIDER);
dest.setLatitude(destLat);
dest.setLongitude(destLon);
final Marker marker = mMap.addMarker(new MarkerOptions()
.position(startPosition)
.title("My Car")
.anchor(0.5f,0.5f)
.snippet("Gurugram")
.rotation(new Location(source).bearingTo(dest))
.icon(BitmapDescriptorFactory.fromResource(R.drawable.ic_car)));
final Handler handler = new Handler();
final long start = SystemClock.uptimeMillis();
final long duration = 50000;
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)
* startPosition.longitude;
double lat = t * toPosition.latitude + (1 - t)
* startPosition.latitude;
marker.setPosition(new LatLng(lat, lng));
if(preLatLng==null){
preLatLng=new LatLng(lat,lng);
}
else{
float bearing = (float) bearingBetweenLocations(preLatLng,new LatLng(lat,lng));
rotateMarker(marker, bearing);
marker.setZIndex(bearing);
preLatLng=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);
}
}
}
});
}
Bearing Method
private double bearingBetweenLocations(LatLng latLng1,LatLng latLng2) {
double PI = 3.14159;
double lat1 = latLng1.latitude * PI / 180;
double long1 = latLng1.longitude * PI / 180;
double lat2 = latLng2.latitude * PI / 180;
double long2 = latLng2.longitude * PI / 180;
double dLon = (long2 - long1);
double y = Math.sin(dLon) * Math.cos(lat2);
double x = Math.cos(lat1) * Math.sin(lat2) - Math.sin(lat1)
* Math.cos(lat2) * Math.cos(dLon);
double brng = Math.atan2(y, x);
brng = Math.toDegrees(brng);
brng = (brng + 360) % 360;
return brng;
}
Marker Rotation method rotateMarker rotates the marker with a rotation value.
private boolean isMarkerRotating=false;
private void rotateMarker(final Marker marker, final float toRotation) {
if(!isMarkerRotating) {
final Handler handler = new Handler();
final long start = SystemClock.uptimeMillis();
final float startRotation = marker.getRotation();
final long duration = 2000;
final Interpolator interpolator = new LinearInterpolator();
handler.post(new Runnable() {
#Override
public void run() {
isMarkerRotating = true;
long elapsed = SystemClock.uptimeMillis() - start;
float t = interpolator.getInterpolation((float) elapsed / duration);
float rot = t * toRotation + (1 - t) * startRotation;
float bearing = -rot > 180 ? rot / 2 : rot;
marker.setRotation(bearing);
if (t < 1.0) {
// Post again 16ms later.
handler.postDelayed(this, 16);
} else {
isMarkerRotating = false;
}
}
});
}
}

How to move an image over the path between two location on map in android

I am working on a project in which I am showing two random location and the path between them.I have used this tutorial to accomplish.
Now i want to show the moving image from one location to another.I have already put markers on that two locations.and also I have saved the position in an arraylist.
I had found some similar posts but couldn't solve my issue.
Here is my code for moving the drawable:
mMap.setOnMarkerClickListener(new GoogleMap.OnMarkerClickListener() {
final Handler handler = new Handler();
int i = 0;
#Override
public boolean onMarkerClick(Marker marker) {
// System.out.println("Marker size:- " + MarkerPoints.size());
handler.post(new Runnable() {
#Override
public void run() {
BitmapDescriptor icon = BitmapDescriptorFactory.fromResource(R.drawable.truck_16);
while (i < MarkerPoints.size()) {
MarkerOptions markerOptions = new MarkerOptions().position(MarkerPoints.get(i))
.title("Current Location")
icon(icon);
System.out.println(MarkerPoints.get(i));
mMap.addMarker(markerOptions);
i++;
handler.postDelayed(this, 3000);
}
}
});
return true;
}
});

private double bearingBetweenLocations(LatLng latLng1, LatLng latLng2) {
final double PI = 3.14159;
final double lat1 = latLng1.latitude * PI / 180;
final double long1 = latLng1.longitude * PI / 180;
final double lat2 = latLng2.latitude * PI / 180;
final double long2 = latLng2.longitude * PI / 180;
final double dLon = (long2 - long1);
final double y = Math.sin(dLon) * Math.cos(lat2);
final double x = Math.cos(lat1) * Math.sin(lat2) - Math.sin(lat1)
* Math.cos(lat2) * Math.cos(dLon);
double brng = Math.atan2(y, x);
brng = Math.toDegrees(brng);
brng = (brng + 360) % 360;
return brng;
}

Suppose you have current and destination co-ordinates like below.
private LatLng CURRENT_LOC = new LatLng(23.013171, 72.522300);
private LatLng DESTINATION_LOC = new LatLng(23.013481, 72.522496);
After that add marker on google map
if (googleMap != null)
{
BitmapDescriptor icon = BitmapDescriptorFactory.fromResource(R.drawable.truck_16);
MarkerOptions current = new MarkerOptions().position(CURRENT_LOC).title("Current Point");
current_marker = googleMap.addMarker(current);
current_marker.setIcon(icon);
current_marker.setFlat(true);
MarkerOptions destination = new MarkerOptions().position(DESTINATION_LOC).title("Destination Point");
destination_marker = googleMap.addMarker(destination);
destination_marker.setFlat(true);
}
And move marker on click
#Override
public void onClick(View v)
{
switch (v.getId())
{
case R.id.btn_move:
float rotate = (float) bearingBetweenLocations(CURRENT_LOC, DESTINATION_LOC);
rotateMarker(rotate);
break;
}
}
below all are methods that move marker from current location to destnation
private double bearingBetweenLocations(LatLng latLng1,LatLng latLng2)
{
double PI = 3.14159;
double lat1 = latLng1.latitude * PI / 180;
double long1 = latLng1.longitude * PI / 180;
double lat2 = latLng2.latitude * PI / 180;
double long2 = latLng2.longitude * PI / 180;
double dLon = (long2 - long1);
double y = Math.sin(dLon) * Math.cos(lat2);
double x = Math.cos(lat1) * Math.sin(lat2) - Math.sin(lat1)
* Math.cos(lat2) * Math.cos(dLon);
double brng = Math.atan2(y, x);
brng = Math.toDegrees(brng);
brng = (brng + 360) % 360;
return brng;
}
public void rotateMarker(float rotate)
{
if (current_marker != null)
{
//final LatLngInterpolator latLngInterpolator = new LatLngInterpolator.LinearFixed();
ValueAnimator valueAnimator = new ValueAnimator();
//final LatLng startPosition = current_marker.getPosition();
final float startRotation = current_marker.getRotation();
final float angle = 180 - Math.abs(Math.abs(startRotation - rotate) - 180);
final float right = WhichWayToTurn(startRotation, rotate);
valueAnimator.addUpdateListener(new ValueAnimator.AnimatorUpdateListener()
{
#Override
public void onAnimationUpdate(ValueAnimator animation)
{
try
{
if (current_marker == null) // oops... destroying map during animation...
{
return;
}
float v = animation.getAnimatedFraction();
//newPosition = latLngInterpolator.interpolate(v, startPosition, toLatLng(location));
float rotation = startRotation + right * v * angle;
current_marker.setRotation(rotation);
//current_marker.setPosition(newPosition);
}
catch (Exception ex)
{
ex.printStackTrace();
}
}
});
valueAnimator.addListener(new AnimatorListenerAdapter()
{
#Override
public void onAnimationEnd(Animator animation)
{
//current_marker.setPosition(newPosition);
animateMarker(current_marker, DESTINATION_LOC, false);
}
});
valueAnimator.setFloatValues(0, 1);
valueAnimator.setDuration(1000);
valueAnimator.start();
}
}
public void animateMarker(final Marker marker, final LatLng toPosition, final boolean hideMarker)
{
final Handler handler = new Handler();
final long start = SystemClock.uptimeMillis();
Projection proj = googleMap.getProjection();
Point startPoint = proj.toScreenLocation(marker.getPosition());
final LatLng startLatLng = proj.fromScreenLocation(startPoint);
final long duration = 5000;
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);
}
}
}
});
}
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;
}
}
Hope this would help you.

Finally I found a way to accomplish this.May be this is not the best way but it solves the problem.I am posting this so in future if someone needs to do stuff like that,It can be helpful.
I have store all the points in an ArrayList called MarkerPoints that we get from the API and use it to draw the image on ever point.
Here is the code:
public class MyActivity extends FragmentActivity implements Runnable
{
private Thread thread = null;
volatile boolean isRunning;
private ArrayList<LatLng> MarkerPoints; //This arrayList contains all points that are on the route
int i = 0;
Marker marker;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_on_trip_maps);
isRunning = true;
}
#Override
public void run() {
while (isRunning) {
runOnUiThread(new Runnable() {
#Override
public void run() {
update();
}
});
control();
}
}
public void update() {
if (marker != null) {
marker.remove();
}
BitmapDescriptor icon = BitmapDescriptorFactory.fromResource(R.drawable.truck_16);
marker = mMap.addMarker(new MarkerOptions().position(MarkerPoints.get(i))
.title("Current Location")
.icon(icon));
System.out.println(MarkerPoints.get(i));
i++;
if (i > MarkerPoints.size() - 1) {
isRunning = false;
}
}
public void control() {
try {
thread.sleep(100);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
This will give the moving effect.

Rotate marker/car icon in google maps - Android

I am trying to crate a app like ola/uber. I want to move the icon and rotate when road turn left or right. I am using following code.
private void rotateMarker(final Marker marker, final float toRotation) {
if(!isMarkerRotating) {
final Handler handler = new Handler();
final long start = SystemClock.uptimeMillis();
final float startRotation = marker.getRotation();
final long duration = 1000;
final Interpolator interpolator = new LinearInterpolator();
handler.post(new Runnable() {
#Override
public void run() {
isMarkerRotating = true;
long elapsed = SystemClock.uptimeMillis() - start;
float t = interpolator.getInterpolation((float) elapsed / duration);
float rot = t * toRotation + (1 - t) * startRotation;
marker.setRotation(-rot > 180 ? rot / 2 : rot);
if (t < 1.0) {
// Post again 16ms later.
handler.postDelayed(this, 16);
} else {
isMarkerRotating = false;
}
}
});
}
}
To calculate bearing:
currentLocation = location;
if(previousLocaton!=null){
previousLocaton = tempLocation;
tempLocation = currentLocation;
Log.d("previousLocaton=====> ",""+previousLocaton);
Log.d("currentLocation=====> ",""+currentLocation);
bearing = previousLocaton.bearingTo(currentLocation) ;
}else{
previousLocaton = location;
tempLocation = location;
}
To set the bearing:
CameraPosition cameraPosition = new CameraPosition.Builder()
.target(latLng).zoom(14).bearing(bearing).build();
To rotate the marker I call roateMarker method in onLocationChanged changed method:
currLocationMarker = mMap.addMarker(markerOptions);
rotateMarker(currLocationMarker,bearing);
Now my icon is rotating. But google map also get rotating. I want rotate icon alone. I refer the following link for animate and move the marker. Link 1. Please let me any idea to solve my issue.

there is simple method available for marker
marker.rotation(float value)
Sets the rotation of the marker in degrees clockwise about the marker's anchor point. The axis of rotation is perpendicular to the marker. A rotation of 0 corresponds to the default position of the marker. When the marker is flat on the map, the default position is North aligned and the rotation is such that the marker always remains flat on the map. When the marker is a billboard, the default position is pointing up and the rotation is such that the marker is always facing the camera. The default value is 0.

To rotate only the marker set rotation to marker using setRotation(float) method.
static public void rotateMarker(final Marker marker, final float toRotation) {
final Handler handler = new Handler();
final long start = SystemClock.uptimeMillis();
final float startRotation = marker.getRotation();
final long duration = 1000;
final Interpolator interpolator = new LinearInterpolator();
L.d("Bearing: "+toRotation);
handler.post(new Runnable() {
#Override
public void run() {
long elapsed = SystemClock.uptimeMillis() - start;
float t = interpolator.getInterpolation((float) elapsed / duration);
float rot = t * toRotation + (1 - t) * startRotation;
marker.setRotation(-rot > 180 ? rot / 2 : rot);
if (t < 1.0) {
// Post again 10ms later.
handler.postDelayed(this, 10);
}
}
});
}

Try this :
public void animateMarker(final LatLng toPosition, final LatLng startLatLng,
final boolean hideMarker) {
final Handler handler = new Handler();
final long start = SystemClock.uptimeMillis();
Projection proj = map.getProjection();
Point startPoint = proj.toScreenLocation(d_marker.getPosition());
final LatLng startLatLng = proj.fromScreenLocation(startPoint);
// final CameraPosition newcameraPosition = null;
final Interpolator interpolator = new LinearInterpolator();
handler.post(new Runnable() {
#Override
public void run() {
Location prevLoc = new Location("service Provider");
prevLoc.setLatitude(startLatLng.latitude);
prevLoc.setLongitude(startLatLng.longitude);
Location newLoc = new Location("service Provider");
newLoc.setLatitude(toPosition.latitude);
newLoc.setLongitude(toPosition.longitude);
System.out.println("Locations ---- " + prevLoc + "-" + newLoc);
float bearing = prevLoc.bearingTo(newLoc);
long elapsed = SystemClock.uptimeMillis() - start;
float t = interpolator.getInterpolation((float) elapsed
/ 1000);
double lng = t * toPosition.longitude + (1 - t)
* startLatLng.longitude;
double lat = t * toPosition.latitude + (1 - t)
* startLatLng.latitude;
d_marker.setPosition(new LatLng(lat, lng));
d_marker.setRotation(bearing);
d_marker.setFlat(true);
// googleMap.moveCamera(CameraUpdateFactory.newCameraPosition(newcameraPosition));
if (t < 1.0) {
// Post again 16ms later.
handler.postDelayed(this, 16);
} else {
if (hideMarker) {
d_marker.setVisible(false);
} else {
d_marker.setVisible(true);
}
}
}
});
}

Try Below method:
public void animateMarker(final LatLng toPosition,
final boolean hideMarker) {
final Handler handler = new Handler();
final long start = SystemClock.uptimeMillis();
Projection proj = googleMap.getProjection();
Point startPoint = proj.toScreenLocation(cabMarker.getPosition());
final LatLng startLatLng = proj.fromScreenLocation(startPoint);
// final CameraPosition newcameraPosition = null;
final Interpolator interpolator = new LinearInterpolator();
handler.post(new Runnable() {
#Override
public void run() {
Location prevLoc = new Location("service Provider");
prevLoc.setLatitude(startLatLng.latitude);
prevLoc.setLongitude(startLatLng.longitude);
Location newLoc = new Location("service Provider");
newLoc.setLatitude(toPosition.latitude);
newLoc.setLongitude(toPosition.longitude);
System.out.println("Locations ---- " + prevLoc + "-" + newLoc);
float bearing = prevLoc.bearingTo(newLoc);
long elapsed = SystemClock.uptimeMillis() - start;
float t = interpolator.getInterpolation((float) elapsed
/ 1000);
double lng = t * toPosition.longitude + (1 - t)
* startLatLng.longitude;
double lat = t * toPosition.latitude + (1 - t)
* startLatLng.latitude;
cabMarker.setPosition(new LatLng(lat, lng));
cabMarker.setRotation(bearing);
// googleMap.moveCamera(CameraUpdateFactory.newCameraPosition(newcameraPosition));
if (t < 1.0) {
// Post again 16ms later.
handler.postDelayed(this, 16);
} else {
if (hideMarker) {
cabMarker.setVisible(false);
} else {
cabMarker.setVisible(true);
}
}
}
});
}

Marker move on map but sometimes it is revolving at 360 degree in android

I am facing an issue right now I am developing an Android app similar to Uber or lyft but the problem that I am facing is the car is moving on the map smoothly but sometimes it is revolving at 360 degree at one position, I need to stop that please help, here is my animation code.
private void animateMarkr(double laat, double lnng,Location prevLocation)
{
final LatLng toPosition=new LatLng(laat,lnng);
final Handler handler = new Handler();
final long start = SystemClock.uptimeMillis();
Projection proj = mGoogleMap.getProjection();
Point startPoint = proj.toScreenLocation(carMarker.getPosition());
final LatLng startLatLng = proj.fromScreenLocation(startPoint);
final long duration = 3000;
final boolean hideMarker=false;
final Interpolator interpolator = new LinearInterpolator();
handler.post(new Runnable() {
#Override
public void run() {
long elapsed = SystemClock.uptimeMillis() - start;
LatLng pre=carMarker.getPosition();
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;
// carMarker.setRotation(getBearing(pre,new LatLng(lat,lng)));
carMarker.setPosition(new LatLng(lat, lng));
if (t < 1.0) {
// Post again 16ms later.
handler.postDelayed(this, 20);
} else {
if (hideMarker) {
carMarker.setVisible(false);
} else {
carMarker.setVisible(true);
}
}
}
});
}
Here is my Rotation Code
private void rotateMarker(Location location,Location preLocation){
Location prevLocation = new Location(LocationManager.GPS_PROVIDER);
prevLocation.setLatitude(carMarker.getPosition().latitude);
prevLocation.setLongitude(carMarker.getPosition().longitude);
final float toRotation = prevLocation.bearingTo(location);
performRotaion(toRotation);
}
private void performRotaion(final float toRotation){
if(!isMarkerRotating) {
final Handler handler = new Handler();
final long start = SystemClock.uptimeMillis();
final float startRotation = carMarker.getRotation();
final float totalDegree=0;
final long duration = 1000;
final Interpolator interpolator = new LinearInterpolator();
handler.post(new Runnable() {
#Override
public void run() {
isMarkerRotating = true;
long elapsed = SystemClock.uptimeMillis() - start;
float t = interpolator.getInterpolation((float) elapsed / duration);
float rot = t toRotation + (1 - t) startRotation;
if(carMarker != null){
carMarker.setAnchor(0.5f, 0.5f);
// if(rot<0.0f && rot>-355.0f) {
carMarker.setRotation(-rot > 180 ? rot / 2 : rot);
carMarker.setFlat(true);
}
if (t < 1.0) {
handler.postDelayed(this, 16);
} else {
isMarkerRotating = false;
}
}
});
}
}
// method call
rotateMarker(location,previcsLocation);
animateMarkr(location.getLatitude(), location.getLongitude(),previcsLocation);
I have implemented the check to stop rotation if the degree is 360 also I have checked if the degree is more than 180 degree than divide the same and move the car on that angle. But nothing works

Before calling these functions
rotateMarker(location,previcsLocation);
animateMarkr(location.getLatitude(), location.getLongitude(),previcsLocation);
in your code. You'll have to add a check for the new (Latitude,Logitude) which comes through the server and marker's (Latitude,Logitude) if both values are same then you should avoid to call the above functions.
Only you have to add this condition in it.
LatLng new_location = new LatLng(data.getLatitude(), data.getLongitude());
//new_location is coming through the server
LatLng current_location = marker.getPosition();
//this is the marker's location
if (current_location != new_location) {
if (current_location.equals(new_location)) {
Log.d(TAG, "LatLng " + "---------current_location-" + current_location);
Log.d(TAG, "LatLng " + "---------new_location-" + new_location);
return;
}
rotateMarker(location,previcsLocation);
animateMarkr(location.getLatitude(), location.getLongitude(),previcsLocation);
}
It worked in my project.

Drop marker slowly from top of screen to location on android map V2

I am using android maps v2works fine I can add and remove markers onLong Touch on locations.
Problem:
I would like to drop the marker slowly into the touched location i.e. I want the user to see the marker floating from the top of the screen to the point where it is dropped(touched location).
Currently; the marker just appears on the touched location such that you have to lift you finger to see that it has been dropped. It would be nice to see it coming from the top of the screen.
Thanks.

You can achieve this with a code similar to this (untested):
final LatLng target = ...;
final long duration = 400;
final Handler handler = new Handler();
final long start = SystemClock.uptimeMillis();
Projection proj = map.getProjection();
Point startPoint = proj.toScreenLocation(target);
startPoint.y = 0;
final LatLng startLatLng = proj.fromScreenLocation(startPoint);
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 * target.longitude + (1 - t) * startLatLng.longitude;
double lat = t * target.latitude + (1 - t) * startLatLng.latitude;
marker.setPosition(new LatLng(lat, lng));
if (t < 1.0) {
// Post again 10ms later.
handler.postDelayed(this, 10);
} else {
// animation ended
}
}
});

I have combined the MaciejGórski's approach with the code from this gist. In addition, added a bounce effect.
public class MyBounceInterpolator implements android.view.animation.Interpolator {
double mAmplitude = 1;
double mFrequency = 10;
public MyBounceInterpolator(double amplitude, double frequency) {
mAmplitude = amplitude;
mFrequency = frequency;
}
public float getInterpolation(float time) {
double amplitude = mAmplitude;
if (amplitude == 0) { amplitude = 0.05; }
// The interpolation curve equation:
// -e^(-time / amplitude) * cos(frequency * time) + 1
//
// View the graph live: https://www.desmos.com/calculator/6gbvrm5i0s
return (float) (-1 * Math.pow(Math.E, -time/ mAmplitude) * Math.cos(mFrequency * time) + 1);
}
}
void dropMarker(final Marker marker, GoogleMap map) {
final LatLng finalPosition = new LatLng(marker.getPosition().latitude, marker.getPosition().longitude);
Projection projection = map.getProjection();
Point startPoint = projection.toScreenLocation(finalPosition);
startPoint.y = 0;
final LatLng startLatLng = projection.fromScreenLocation(startPoint);
final Interpolator interpolator = new MyBounceInterpolator(0.11, 4.6);
TypeEvaluator<LatLng> typeEvaluator = new TypeEvaluator<LatLng>() {
#Override
public LatLng evaluate(float fraction, LatLng startValue, LatLng endValue) {
float t = interpolator.getInterpolation(fraction);
double lng = t * finalPosition.longitude + (1 - t) * startLatLng.longitude;
double lat = t * finalPosition.latitude + (1 - t) * startLatLng.latitude;
return new LatLng(lat, lng);
}
};
Property<Marker, LatLng> property = Property.of(Marker.class, LatLng.class, "position");
ObjectAnimator animator = ObjectAnimator.ofObject(marker, property, typeEvaluator, finalPosition);
animator.setDuration(400);
animator.start();
}

It works great, but it seemed to me that sometimes the marker remained one step far from the target, so I added just one more line:
if (t < 1.0) {
// Post again 10ms later.
handler.postDelayed(this, 50);
} else {
// animation ended
marker.setPosition(target);
}
Hope it helps.

I've applied your way but have an issue that is the markers position on map is not correct. I think command below calculate is not correct. So after animation finished then final result is not same as original Lat,Lng.
double lng = t * target.longitude + (1 - t) * startLatLng.longitude;
double lat = t * target.latitude + (1 - t) * startLatLng.latitude;