我正在尝试使用Latitude从设备中获取Longitude和FusedLocationApi。如果该位置已关闭，我要求用户通过dialog开启位置服务。一旦我启用了位置服务，我就会收到Longitude和Latitude。但有时它返回Location为null。以下是使用Latitude获取Longitude和FusedLocationApi的代码。 当用户必须使用对话框
private void getLatLong() {
mGoogleApiClient = new GoogleApiClient.Builder(this)
// The next two lines tell the new client that “this” current class will handle connection stuff
.addConnectionCallbacks(this)
.addOnConnectionFailedListener(this)
//fourth line adds the LocationServices API endpoint from GooglePlayServices
.addApi(LocationServices.API)
.build();
}
@Override
protected void onPause() {
super.onPause();
overridePendingTransition(0, 0);
//Disconnect from API onPause()
if (mGoogleApiClient.isConnected()) {
LocationServices.FusedLocationApi.removeLocationUpdates(mGoogleApiClient, this);
mGoogleApiClient.disconnect();
}
}
@Override
public void onResume() {
super.onResume();
//Now lets connect to the API
mGoogleApiClient.connect();
}
@Override
public void onConnected(@Nullable Bundle bundle) {
if (mGoogleApiClient.isConnected()) {
Log.e("GoogleApiClient", "Connected");
settingsRequest();
}
}
private void settingsRequest() {
mLocationRequest = LocationRequest.create()
.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY)
.setInterval(10 * 1000) // 10 seconds, in milliseconds
.setFastestInterval(1000); // 1 second, in milliseconds
LocationSettingsRequest.Builder builder = new LocationSettingsRequest.Builder().addLocationRequest(mLocationRequest);
builder.setAlwaysShow(true); //this is the key ingredient
PendingResult<LocationSettingsResult> result = LocationServices.SettingsApi.checkLocationSettings(mGoogleApiClient, builder.build());
result.setResultCallback(new ResultCallback<LocationSettingsResult>() {
@Override
public void onResult(LocationSettingsResult result) {
final Status status = result.getStatus();
Log.e("StatusCode", status.getStatusCode() + "");
switch (status.getStatusCode()) {
case LocationSettingsStatusCodes.SUCCESS:
Log.e("GoogleAfterLocation", mGoogleApiClient.isConnected() + "");
if (mGoogleApiClient.isConnected()) {
// check if the device has OS Marshmellow or greater than
if (Build.VERSION.SDK_INT > Build.VERSION_CODES.LOLLIPOP_MR1) {
if (ActivityCompat.checkSelfPermission(RegistrationActivity.this, android.Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(RegistrationActivity.this, android.Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
ActivityCompat.requestPermissions(RegistrationActivity.this, new String[]{android.Manifest.permission.ACCESS_FINE_LOCATION}, ACCESS_FINE_LOCATION_CODE);
} else {
// get Location
Location location = LocationServices.FusedLocationApi.getLastLocation(mGoogleApiClient);
Log.e("Location", location + "");
if (location == null) {
LocationServices.FusedLocationApi.requestLocationUpdates(mGoogleApiClient, mLocationRequest, RegistrationActivity.this);
Alerter.create(RegistrationActivity.this)
.setTitle(R.string.warning)
.setDuration(2000)
.setBackgroundColor(R.color.dot_dark_screen1)
.setText("Please turn on the Location from settings and start the application")
.show();
} else {
//If everything went fine lets get latitude and longitude
currentLatitude = location.getLatitude();
currentLongitude = location.getLongitude();
if (currentLatitude != -0.0 && currentLongitude != -0.0) {
//Get Weather Data
//getWeatherData(currentLatitude, currentLongitude);
Log.e("PermissionGranted", currentLatitude + " " + currentLongitude);
} else {
Alerter.create(RegistrationActivity.this)
.setTitle(R.string.warning)
.setText("Please Check internet connectivity")
.setDuration(1500)
.setBackgroundColor(R.color.dot_dark_screen1)
.show();
}
// Toast.makeText(this, currentLatitude + " WORKS " + currentLongitude + "", Toast.LENGTH_LONG).show();
}
}
} else {
// get Location
Location location = LocationServices.FusedLocationApi.getLastLocation(mGoogleApiClient);
if (location == null) {
LocationServices.FusedLocationApi.requestLocationUpdates(mGoogleApiClient, mLocationRequest, RegistrationActivity.this);
} else {
//If everything went fine lets get latitude and longitude
currentLatitude = location.getLatitude();
currentLongitude = location.getLongitude();
if (currentLatitude != -0.0 && currentLongitude != -0.0) {
//Get Weather Data
//getWeatherData(currentLatitude, currentLongitude);
Log.e("Lollipop", currentLatitude + " " + currentLongitude);
} else {
Alerter.create(RegistrationActivity.this)
.setTitle(R.string.warning)
.setText("Please Check internet connectivity")
.setDuration(1500)
.setBackgroundColor(R.color.dot_dark_screen1)
.show();
}
// Toast.makeText(this, currentLatitude + " WORKS " + currentLongitude + "", Toast.LENGTH_LONG).show();
}
}
}
break;
case LocationSettingsStatusCodes.RESOLUTION_REQUIRED:
// Location settings are not satisfied. But could be fixed by showing the user
// a dialog.
try {
// Show the dialog by calling startResolutionForResult(),
// and check the result in onActivityResult().
status.startResolutionForResult(RegistrationActivity.this, REQUEST_RESOLVE_ERROR);
} catch (IntentSender.SendIntentException e) {
// Ignore the error.
}
break;
case LocationSettingsStatusCodes.SETTINGS_CHANGE_UNAVAILABLE:
// Location settings are not satisfied. However, we have no way to fix the
// settings so we won't show the dialog.
break;
}
}
});
}
// This method is called only on devices having installed Android version >= M (Marshmellow)
// This method is just to show the user options for allow or deny location services at runtime
@Override
public void onRequestPermissionsResult(int requestCode, String permissions[], int[] grantResults) {
switch (requestCode) {
case 3310: {
if (grantResults.length > 0) {
for (int i = 0, len = permissions.length; i < len; i++) {
if (grantResults[i] == PackageManager.PERMISSION_DENIED) {
// Show the user a dialog why you need location
} else if (grantResults[i] == PackageManager.PERMISSION_GRANTED) {
// get Location
getLatLong();
} else {
finish();
}
}
}
return;
}
}
}
@Override
public void onActivityResult(int requestCode, int resultCode, Intent data) {
Log.e("RequestCode", requestCode + "");
if (requestCode == REQUEST_RESOLVE_ERROR) {
mResolvingError = false;
switch (resultCode) {
case Activity.RESULT_OK:
Log.e("LocationDialog", "Turned On");
// get location method
if (ActivityCompat.checkSelfPermission(RegistrationActivity.this, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(RegistrationActivity.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;
}
Location location = LocationServices.FusedLocationApi.getLastLocation(mGoogleApiClient);
if (location == null) {
LocationServices.FusedLocationApi.requestLocationUpdates(mGoogleApiClient, mLocationRequest, RegistrationActivity.this);
} else {
//If everything went fine lets get latitude and longitude
currentLatitude = location.getLatitude();
currentLongitude = location.getLongitude();
if (currentLatitude != -0.0 && currentLongitude != -0.0) {
//Get Weather Data
//getWeatherData(currentLatitude, currentLongitude);
} else {
Alerter.create(RegistrationActivity.this)
.setTitle(R.string.warning)
.setText("Please Check internet connectivity")
.setDuration(1500)
.setBackgroundColor(R.color.dot_dark_screen1)
.show();
}
//Toast.makeText(getActivity(), currentLatitude + " WORKS " + currentLongitude + "", Toast.LENGTH_LONG).show();
}
break;
case Activity.RESULT_CANCELED:
finish();
break;
}
}
}
@Override
public void onConnectionSuspended(int i) {
}
@Override
public void onConnectionFailed(@NonNull 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()) {
try {
mResolvingError = true;
// Start an Activity that tries to resolve the error
connectionResult.startResolutionForResult(RegistrationActivity.this, CONNECTION_FAILURE_RESOLUTION_REQUEST);
/*
* Thrown if Google Play services canceled the original
* PendingIntent
*/
} catch (IntentSender.SendIntentException e) {
// Log the error
mGoogleApiClient.connect();
}
} else {
/*
* If no resolution is available, display a dialog to the
* user with the error.
*/
showErrorDialog(connectionResult.getErrorCode());
mResolvingError = true;
Log.e("Error", "Location services connection failed with code " + connectionResult.getErrorCode());
}
}
/* Creates a dialog for an error message */
private void showErrorDialog(int errorCode) {
// Create a fragment for the error dialog
ErrorDialogFragment dialogFragment = new ErrorDialogFragment();
// Pass the error that should be displayed
Bundle args = new Bundle();
args.putInt(DIALOG_ERROR, errorCode);
dialogFragment.setArguments(args);
dialogFragment.show(getSupportFragmentManager(), "errordialog");
}
/* Called from ErrorDialogFragment when the dialog is dismissed. */
public static void onDialogDismissed() {
mResolvingError = false;
}
/* A fragment to display an error dialog */
public static class ErrorDialogFragment extends DialogFragment {
public ErrorDialogFragment() {
}
@Override
public Dialog onCreateDialog(Bundle savedInstanceState) {
// Get the error code and retrieve the appropriate dialog
int errorCode = this.getArguments().getInt(DIALOG_ERROR);
return GoogleApiAvailability.getInstance().getErrorDialog(
this.getActivity(), errorCode, REQUEST_RESOLVE_ERROR);
}
@Override
public void onDismiss(DialogInterface dialog) {
onDialogDismissed();
}
}
@Override
public void onLocationChanged(Location location) {
currentLatitude = location.getLatitude();
currentLongitude = location.getLongitude();
}
该位置打开后，此行返回null：
Location location = LocationServices.FusedLocationApi.getLastLocation(mGoogleApiClient);