google 片段中的地图未使用融合位置移动到当前位置 api

Question

我想在地图上显示当前位置，我的地图是片段的，我在非 activity class 中使用融合位置提供程序，但是当地图已加载，只有当我按下我的位置按钮时它才会给我当前位置，但我希望在加载地图时它应该显示我的当前位置而不是世界地图。

locationprovide.java

public class LocationProvider implements
        GoogleApiClient.ConnectionCallbacks,
        GoogleApiClient.OnConnectionFailedListener,
        LocationListener {


    public interface LocationCallback {
        public void handleNewLocation(Location location);
    }



    public static final String TAG = LocationProvider.class.getSimpleName();

    /*
     * Define a request code to send to Google Play services
     * This code is returned in Activity.onActivityResult
     */
    private final static int CONNECTION_FAILURE_RESOLUTION_REQUEST = 9000;

    private LocationCallback mLocationCallback;
    private Context mContext;
    private GoogleApiClient mGoogleApiClient;
    private LocationRequest mLocationRequest;

    public LocationProvider(Context context,LocationCallback locationCallback) {
        mGoogleApiClient = new GoogleApiClient.Builder(context)
                .addConnectionCallbacks(this)
                .addOnConnectionFailedListener(this)
                .addApi(LocationServices.API)
                .build();
        mContext = context;
        mLocationCallback = locationCallback;

        mLocationRequest = new LocationRequest();
        mLocationRequest.setInterval(1000);
        mLocationRequest.setFastestInterval(1000);
        mLocationRequest.setPriority(LocationRequest.PRIORITY_BALANCED_POWER_ACCURACY);



    }

    public void connect() {
        mGoogleApiClient.connect();
    }

    public void disconnect() {
        if (mGoogleApiClient.isConnected()) {
            LocationServices.FusedLocationApi.removeLocationUpdates(mGoogleApiClient, this);
            mGoogleApiClient.disconnect();
        }
    }

    @Override
    public void onConnected(Bundle bundle) {
        Log.i(TAG, "Location services connected.");


        if (ActivityCompat.checkSelfPermission(mContext, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED &&
                ActivityCompat.checkSelfPermission(mContext, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
            // TODO: Consider calling
            //    ActivityCompat#requestPermissions
            // here to request the missing permissions, and then overriding
            //   public void onRequestPermissionsResult(int requestCode, String[] permissions,
            //                                          int[] grantResults)
            // to handle the case where the user grants the permission. See the documentation
            // for ActivityCompat#requestPermissions for more details.
            return;
        }
        Location location = LocationServices.FusedLocationApi.getLastLocation(mGoogleApiClient);
        if (location == null) {
            LocationServices.FusedLocationApi.requestLocationUpdates(mGoogleApiClient, mLocationRequest, this);
        }
        else {
            mLocationCallback.handleNewLocation(location);
        }
    }

    @Override
    public void onConnectionSuspended(int i) {

    }

    @Override
    public void onConnectionFailed(ConnectionResult connectionResult) {
        /*
         * Google Play services can resolve some errors it detects.
         * If the error has a resolution, try sending an Intent to
         * start a Google Play services activity that can resolve
         * error.
         */
        if (connectionResult.hasResolution() && mContext instanceof Activity) {
            try {
                Activity activity = (Activity)mContext;
                // Start an Activity that tries to resolve the error
                connectionResult.startResolutionForResult(activity, CONNECTION_FAILURE_RESOLUTION_REQUEST);
            /*
             * Thrown if Google Play services canceled the original
             * PendingIntent
             */
            } catch (IntentSender.SendIntentException e) {
                // Log the error
                e.printStackTrace();
            }
        } else {
            /*
             * If no resolution is available, display a dialog to the
             * user with the error.
             */
            Log.i(TAG, "Location services connection failed with code " + connectionResult.getErrorCode());
        }
    }

    @Override
    public void onLocationChanged(Location location) {
        mLocationCallback.handleNewLocation(location);
    }
}

片段

public class ChildMapFragment extends Fragment implements OnMapReadyCallback,LocationProvider.LocationCallback  {

    private LocationProvider mLocationProvider;
    private GoogleMap mMap;
    Location mLastLocation;
    Marker mCurrLocationMarker;
    LocationRequest mLocationRequest;
    Context mContext;
    String sid,cid;

    @Override
    public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {

        View view= inflater.inflate(R.layout.fragment_child_map, container, false);

        SupportMapFragment mapFragment = (SupportMapFragment)this.getChildFragmentManager().findFragmentById(R.id.map);
        mapFragment.getMapAsync(this);

        if (android.os.Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
            checkLocationPermission();
        }else{
            mLocationProvider = new LocationProvider(mContext,this);


        }
        if (mLocationProvider!=null)
            mLocationProvider.connect();
        return view;

    }

    @Override
    public void onViewCreated(View view, @Nullable Bundle savedInstanceState) {
        super.onViewCreated(view, savedInstanceState);
        if (mLocationProvider!=null)
            mLocationProvider.connect();
    }

    @Override
    public void onMapReady(GoogleMap googleMap) {
        mMap = googleMap;

        //Initialize Google Play Services
        if (android.os.Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
            if (ContextCompat.checkSelfPermission(mContext,
                    Manifest.permission.ACCESS_FINE_LOCATION)
                    == PackageManager.PERMISSION_GRANTED) {

                mLocationProvider = new LocationProvider(mContext,this);

                mMap.setMyLocationEnabled(true);
            }
        }
        else {

            mLocationProvider = new LocationProvider(mContext,this);

            mMap.setMyLocationEnabled(true);
        }
    }

    @Override
    public void handleNewLocation(Location location) {
        mLastLocation = location;
        if (mCurrLocationMarker != null) {
            mCurrLocationMarker.remove();
        }

        //Place current location marker
        LatLng latLng = new LatLng(location.getLatitude(), location.getLongitude());
        MarkerOptions markerOptions = new MarkerOptions();
        markerOptions.position(latLng);
        markerOptions.title("Current Position");
        markerOptions.icon(BitmapDescriptorFactory.defaultMarker(BitmapDescriptorFactory.HUE_MAGENTA));
        mCurrLocationMarker = mMap.addMarker(markerOptions);

        //move map camera
        mMap.moveCamera(CameraUpdateFactory.newLatLng(latLng));
        mMap.animateCamera(CameraUpdateFactory.zoomTo(11));


    }

    @Override
    public void onDestroyView() {
        super.onDestroyView();
        mMap.clear();
    }

    @Override
    public void onResume() {
        super.onResume();
        if (mLocationProvider!=null)
        mLocationProvider.connect();
    }

    @Override
    public void onPause() {
        super.onPause();
        if (mLocationProvider!=null)
        mLocationProvider.disconnect();
    }

    @Override
    public void onAttach(Context context) {
        super.onAttach(context);
        mContext=context;

    }

    public static final int MY_PERMISSIONS_REQUEST_LOCATION = 99;
    public boolean checkLocationPermission(){
        if (ContextCompat.checkSelfPermission(mContext,
                Manifest.permission.ACCESS_FINE_LOCATION)
                != PackageManager.PERMISSION_GRANTED) {

            // Asking user if explanation is needed
            if (ActivityCompat.shouldShowRequestPermissionRationale((Activity) mContext,
                    Manifest.permission.ACCESS_FINE_LOCATION)) {

                // Show an explanation to the user *asynchronously* -- don't block
                // this thread waiting for the user's response! After the user
                // sees the explanation, try again to request the permission.

                //Prompt the user once explanation has been shown
                ActivityCompat.requestPermissions((Activity) mContext,
                        new String[]{Manifest.permission.ACCESS_FINE_LOCATION},
                        MY_PERMISSIONS_REQUEST_LOCATION);


            } else {
                // No explanation needed, we can request the permission.
                ActivityCompat.requestPermissions((Activity) mContext,
                        new String[]{Manifest.permission.ACCESS_FINE_LOCATION},
                        MY_PERMISSIONS_REQUEST_LOCATION);
            }
            return false;
        } else {
            return true;
        }
    }

    @Override
    public void onRequestPermissionsResult(int requestCode,
                                           @NonNull String permissions[], @NonNull int[] grantResults) {
        switch (requestCode) {
            case MY_PERMISSIONS_REQUEST_LOCATION: {
                // If request is cancelled, the result arrays are empty.
                if (grantResults.length > 0
                        && grantResults[0] == PackageManager.PERMISSION_GRANTED) {

                    // permission was granted. Do the
                    // contacts-related task you need to do.
                    if (ContextCompat.checkSelfPermission(mContext,
                            Manifest.permission.ACCESS_FINE_LOCATION)
                            == PackageManager.PERMISSION_GRANTED) {

                            mLocationProvider = new LocationProvider(mContext,this);

                        mMap.setMyLocationEnabled(true);
                    }

                } else {

                    // Permission denied, Disable the functionality that depends on this permission.
                    Toast.makeText(mContext, "permission denied", Toast.LENGTH_LONG).show();
                }
                return;
            }       
        }
    }   
}

Answer 1

把代码放在下面

if (mLocationProvider!=null){
     mLocationProvider.connect();
}

您使用的地方

mLocationProvider = new LocationProvider(mContext,this);