启用 GPS 后使用以下代码获取当前位置;
public class MainActivity extends AppCompatActivity implements LocationListener,
GoogleApiClient.ConnectionCallbacks,
GoogleApiClient.OnConnectionFailedListener, OnMapReadyCallback {
final String TAG = "GPS";
GoogleMap googleMap;
Marker mCurrLocationMarker;
private long UPDATE_INTERVAL = 2 * 1000; /* 10 secs */
private long FASTEST_INTERVAL = 2000; /* 2 sec */
static final int MY_PERMISSIONS_REQUEST_ACCESS_FINE_LOCATION = 1;
private static final int GPS_CHECK = 112;
GoogleApiClient gac;
LocationRequest locationRequest;
TextView tvLatitude, tvLongitude, tvTime;
LocationManager locationManager;
Button capture;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
tvLatitude = (TextView) findViewById(R.id.tvLatitude);
tvLongitude = (TextView) findViewById(R.id.tvLongitude);
tvTime = (TextView) findViewById(R.id.tvTime);
capture = (Button) findViewById(R.id.capture);
isGooglePlayServicesAvailable();
// if (!isLocationEnabled())
// showAlert();
locationManager = (LocationManager) getSystemService(LOCATION_SERVICE);
if (!locationManager.isProviderEnabled(LocationManager.GPS_PROVIDER)) {
showAlert();
}
locationRequest = new LocationRequest();
locationRequest.setInterval(UPDATE_INTERVAL);
locationRequest.setFastestInterval(FASTEST_INTERVAL);
locationRequest.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY);
gac = new GoogleApiClient.Builder(this)
.addConnectionCallbacks(this)
.addOnConnectionFailedListener(this)
.addApi(LocationServices.API)
.build();
SupportMapFragment mapFragment = (SupportMapFragment)
getSupportFragmentManager()
.findFragmentById(R.id.map);
mapFragment.getMapAsync(this);
}
@Override
protected void onStart() {
gac.connect();
super.onStart();
}
@Override
protected void onStop() {
gac.disconnect();
super.onStop();
}
@Override
public void onLocationChanged(Location location) {
if (location != null) {
updateUI(location);
}
}
@Override
public void onConnected(@Nullable Bundle bundle) {
if (ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION)
!= PackageManager.PERMISSION_GRANTED
&& ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_COARSE_LOCATION)
!= PackageManager.PERMISSION_GRANTED) {
ActivityCompat.requestPermissions(MainActivity.this,
new String[]{Manifest.permission.ACCESS_FINE_LOCATION},
MY_PERMISSIONS_REQUEST_ACCESS_FINE_LOCATION);
return;
}
Log.d(TAG, "onConnected");
Location ll = LocationServices.FusedLocationApi.getLastLocation(gac);
Log.d(TAG, "LastLocation: " + (ll == null ? "NO LastLocation" : ll.toString()));
updateUI(ll);
LocationServices.FusedLocationApi.requestLocationUpdates(gac, locationRequest, this);
}
@Override
public void onRequestPermissionsResult(
int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
switch (requestCode) {
case MY_PERMISSIONS_REQUEST_ACCESS_FINE_LOCATION: {
// If request is cancelled, the result arrays are empty.
if (grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
Toast.makeText(MainActivity.this, "Permission was granted!", Toast.LENGTH_LONG).show();
try {
LocationServices.FusedLocationApi.requestLocationUpdates(
gac, locationRequest, this);
} catch (SecurityException e) {
Toast.makeText(MainActivity.this, "SecurityException:\n" + e.toString(), Toast.LENGTH_LONG).show();
}
} else {
Toast.makeText(MainActivity.this, "Permission denied!", Toast.LENGTH_LONG).show();
}
return;
}
}
}
@Override
public void onConnectionSuspended(int i) {
}
@Override
public void onConnectionFailed(@NonNull ConnectionResult connectionResult) {
Toast.makeText(MainActivity.this, "onConnectionFailed: \n" + connectionResult.toString(),
Toast.LENGTH_LONG).show();
Log.d("DDD", connectionResult.toString());
}
private void updateUI(Location loc) {
Log.d(TAG, "updateUI");
try {
tvLatitude.setText(Double.toString(loc.getLatitude()));
tvLongitude.setText(Double.toString(loc.getLongitude()));
tvTime.setText(DateFormat.getTimeInstance().format(loc.getTime()));
double lattitude = loc.getLatitude();
double longitude = loc.getLongitude();
//Place current location marker
LatLng latLng = new LatLng(lattitude, longitude);
if(mCurrLocationMarker!=null){
mCurrLocationMarker.setPosition(latLng);
}else{
mCurrLocationMarker = googleMap.addMarker(new MarkerOptions()
.position(latLng)
.icon(BitmapDescriptorFactory.defaultMarker(BitmapDescriptorFactory.HUE_RED))
.title("I am here"));
}
googleMap.animateCamera(CameraUpdateFactory.newLatLngZoom(latLng, 18));
googleMap.getUiSettings().setZoomControlsEnabled(true);
}
catch (Exception e)
{
}
}
private boolean isLocationEnabled() {
LocationManager locationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
return locationManager.isProviderEnabled(LocationManager.GPS_PROVIDER) ||
locationManager.isProviderEnabled(LocationManager.NETWORK_PROVIDER);
}
private boolean isGooglePlayServicesAvailable() {
final int PLAY_SERVICES_RESOLUTION_REQUEST = 9000;
GoogleApiAvailability apiAvailability = GoogleApiAvailability.getInstance();
int resultCode = apiAvailability.isGooglePlayServicesAvailable(this);
if (resultCode != ConnectionResult.SUCCESS) {
if (apiAvailability.isUserResolvableError(resultCode)) {
apiAvailability.getErrorDialog(this, resultCode, PLAY_SERVICES_RESOLUTION_REQUEST)
.show();
} else {
Log.d(TAG, "This device is not supported.");
finish();
}
return false;
}
Log.d(TAG, "This device is supported.");
return true;
}
private void showAlert() {
final AlertDialog.Builder dialog = new AlertDialog.Builder(this);
dialog.setTitle("Enable Location")
.setMessage("Your Locations Settings is set to 'Off'.\nPlease Enable Location to " +
"use this app")
.setPositiveButton("Location Settings", new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface paramDialogInterface, int paramInt) {
startActivityForResult(new Intent(Settings.ACTION_LOCATION_SOURCE_SETTINGS), GPS_CHECK);
}
})
.setNegativeButton("Cancel", new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface paramDialogInterface, int paramInt) {
}
});
dialog.show();
}
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if (requestCode == GPS_CHECK) {
if (!locationManager.isProviderEnabled(LocationManager.GPS_PROVIDER)) {
capture.setVisibility(View.GONE);
Toast.makeText(getApplicationContext(), "Please turn on gps...", Toast.LENGTH_SHORT).show();
Log.e("BBBBBBBBBBBBBBB", "");
}
else
{
gac.connect();
googleMap.setOnMyLocationButtonClickListener(new GoogleMap.OnMyLocationButtonClickListener() {
@Override
public boolean onMyLocationButtonClick()
{
try
{
Location myLocation = googleMap.getMyLocation();
onLocationChanged(myLocation);
}
catch (Exception e)
{
Log.getStackTraceString(e);
}
return false;
}
});
}
}
}
@Override
public void onMapReady(GoogleMap map) {
googleMap = map;
map.setMapType(GoogleMap.MAP_TYPE_NORMAL);
if (ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(this, 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;
}
map.setMyLocationEnabled(true);
map.setTrafficEnabled(true);
map.setIndoorEnabled(true);
map.setBuildingsEnabled(true);
map.getUiSettings().setZoomControlsEnabled(true);
}
}