MapActivity.java 文件源码

/**
 * Creates a callback for receiving location events.
 */
private void createLocationCallback() {
    mLocationCallback = new LocationCallback() {
        @Override
        public void onLocationResult(final LocationResult locationResult) {
            super.onLocationResult(locationResult);

            if (mRequestingLocationUpdates) {

                Log.i(TAG, "update event");
                Location oldLocation = mCurrentLocation;

                mCurrentLocation = locationResult.getLastLocation();

                if (initialPosition == null) {
                    initialPosition = mCurrentLocation;

                    map.moveCamera(CameraUpdateFactory.newLatLngZoom(
                            new LatLng(initialPosition.getLatitude(),
                                    initialPosition.getLongitude()), DEFAULT_ZOOM));

                    Log.d("INITIAL_POSITION", initialPosition.getLatitude() + " " +
                            initialPosition.getLongitude());

                    createAndDrawPath();
                }

                mLastUpdateTime = DateFormat.getTimeInstance().format(new Date());
                updateUI(oldLocation);
            }

        }
    };
}