Android在这里SDK移动标记

Question

I need to be able to show moving cars using Here maps android sdk. Is it possible in the current version? I tried to remove and add map marker object in a render like loop logic as the following;

// this is a render like loop which is called in each 1 secs
public void update(Map map, float deltaTime) {

    float displacement = mCars.get(0).getVelocity() * deltaTime;
    float delta = displacement / ((float) Math.sqrt(2));

    MapMarker mapMarker = new MapMarker();
    Image image = new Image();
    image.setBitmap(mCars.get(0).getIcon().toBitmap());
    mapMarker.setCoordinate(mCars.get(0).getCoordinate());
    mapMarker.setIcon(image);

    // remove old coordinate
    map.removeMapObject(mapMarker);

    mCars.get(0).addDelta(delta);
    mapMarker.setCoordinate(mCars.get(0).getCoordinate());

    map.addMapObject(mapMarker);
}

The removeMapObject() doesn't seem to be working. Any ideas to have a moving map object ?

Answer 1

The problem here was to create each marker and remove them and re-add them. The render loop would be the following;

// this is a render like loop which is called in each 1 secs
public void update(Map map, float deltaTime) {

    Timber.d("Before coordinate: %f %f", mCars.get(0).getCoordinate().getLatitude(), mCars.get(0).getCoordinate().getLongitude());

    map.removeMapObject(mCars.get(0).getMarker());

    mCars.get(0).addDelta(deltaTime);

    map.addMapObject(mCars.get(0).getMarker());

    Timber.d("Update call, delta time: %f", deltaTime);
}

The addDelta() call should update the marker coordinate and its own coordinate;

public void addDelta(float deltaTime) {

    if (mDestination.equals(mCoordinate)) {
        return;
    }

    double deltaLatitude = mDestination.getLatitude() - mCoordinate.getLatitude();
    double deltaLongitude = mDestination.getLongitude() - mCoordinate.getLongitude();

    double lat = getCoordinate().getLatitude() + (0.01 * deltaLatitude);
    double lng = getCoordinate().getLongitude() + (0.01 * deltaLongitude);

    mCoordinate.setLatitude(lat);
    mCoordinate.setLongitude(lng);

    updateMarker();
}

And lastly, updateMarker implementation is the following;

public void updateMarker() {
    mMarker = new MapMarker();
    Image image = new Image();
    image.setBitmap(mIcon.toBitmap());
    mMarker.setCoordinate(mCoordinate);
    mMarker.setIcon(image);
}