Android Maps API v2:放大当前位置和标记

Question

我有一个包含在应用程序中的地图.我需要地图放大标记和用户位置,但保持标记居中.放大效果很好,但当然不会将标记置于地图上.

@Override
public void onLocationChanged(Location location) {
    if (mListener != null) {
        mListener.onLocationChanged(location);

        LatLngBounds bounds = new LatLngBounds.Builder()
        .include(new LatLng(location.getLatitude(),location.getLongitude()))
        .include((new LatLng(52.3563, 4.8790)))
        .build();

        mMap.animateCamera(CameraUpdateFactory.newLatLngBounds(bounds, 35));


    }
}

将两者保持在界限内但保持标记居中的最佳方法是什么？我似乎无法在官方文档中找到解决方案.

Answer 1

我会调用两个函数,一个用于居中标记,另一个用于放大地图,直到您当前的位置仍然可见.

我缩放到15级缩放点的解决方案:

myMap.moveCamera(CameraUpdateFactory.newLatLngZoom(latLngToCenter, 1));

缩放直到所有标记仍然可见(更改代码以适合标记和您的位置):

public void fitZoomAndPositionToMapByMarkers() {

    int minLat = Integer.MAX_VALUE;
    int maxLat = Integer.MIN_VALUE;
    int minLon = Integer.MAX_VALUE;
    int maxLon = Integer.MIN_VALUE;

    List<MyMapMarker> markersShownOnMap = getMarkersToShow();

    for (MyMapMarker item : markersShownOnMap) {

        int lat = (int) (item.getLatitude() * 1E6);
        int lon = (int) (item.getLongitude() * 1E6);

        maxLat = Math.max(lat, maxLat);
        minLat = Math.min(lat, minLat);
        maxLon = Math.max(lon, maxLon);
        minLon = Math.min(lon, minLon);
    }

    double latitudeToGo = (maxLat + minLat) / 1E6 / 2;
    double longitudeToGo = (maxLon + minLon) / 1E6 / 2;
    LatLng toCenter = new LatLng(latitudeToGo, longitudeToGo);

    centerCameraToProperPosition(toCenter);

    LatLng southWestLatLon = new LatLng(minLat / 1E6, minLon / 1E6);
    LatLng northEastLatLon = new LatLng(maxLat / 1E6, maxLon / 1E6);

    zoomInUntilAllMarkersAreStillVisible(southWestLatLon, northEastLatLon);
}

希望这可以帮助!

private void zoomInUntilAllMarkersAreStillVisible(final LatLng southWestLatLon, final     LatLng northEastLatLon) {

    myMap.setOnCameraChangeListener(new OnCameraChangeListener() {

        @Override
        public void onCameraChange(CameraPosition arg0) {

            myMap.moveCamera(CameraUpdateFactory.newLatLngBounds(new LatLngBounds(southWestLatLon, northEastLatLon), 50));
            myMap.setOnCameraChangeListener(null);

        }
    });

}