在 Android 中显示州名以及纬度和经度

Question

最初我使用以下代码在应用程序中显示当前的纬度和经度：

package com.coders.location;

import android.Manifest;
import android.annotation.SuppressLint;
import android.app.Activity;
import android.content.Intent;
import android.content.pm.PackageManager;
import android.location.Location;
import android.os.Bundle;
import android.support.annotation.NonNull;
import android.support.v4.app.ActivityCompat;
import android.support.v7.app.AppCompatActivity;
import android.widget.Button;
import android.widget.TextView;
import android.widget.Toast;

import com.google.android.gms.location.FusedLocationProviderClient;
import com.google.android.gms.location.LocationCallback;
import com.google.android.gms.location.LocationRequest;
import com.google.android.gms.location.LocationResult;
import com.google.android.gms.location.LocationServices;

import java.util.Locale;

public class MainActivity extends AppCompatActivity {

    private FusedLocationProviderClient mFusedLocationClient;

    private double wayLatitude = 0.0, wayLongitude = 0.0;
    private LocationRequest locationRequest;
    private LocationCallback locationCallback;
    private android.widget.Button btnLocation;
    private TextView txtLocation;
    private android.widget.Button btnContinueLocation;
    private TextView txtContinueLocation;
    private StringBuilder stringBuilder;

    private boolean isContinue = false;
    private boolean isGPS = false;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        this.txtContinueLocation = (TextView) findViewById(R.id.txtContinueLocation);
        this.btnContinueLocation = (Button) findViewById(R.id.btnContinueLocation);
        this.txtLocation = (TextView) findViewById(R.id.txtLocation);
        this.btnLocation = (Button) findViewById(R.id.btnLocation);

        mFusedLocationClient = LocationServices.getFusedLocationProviderClient(this);

        locationRequest = LocationRequest.create();
        locationRequest.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY);
        locationRequest.setInterval(10 * 1000); // 10 seconds
        locationRequest.setFastestInterval(5 * 1000); // 5 seconds

        new GpsUtils(this).turnGPSOn(new GpsUtils.onGpsListener() {
            @Override
            public void gpsStatus(boolean isGPSEnable) {
                // turn on GPS
                isGPS = isGPSEnable;
            }
        });

        locationCallback = new LocationCallback() {
            @Override
            public void onLocationResult(LocationResult locationResult) {
                if (locationResult == null) {
                    return;
                }
                *******************************************************
                for (Location location : locationResult.getLocations()) {
                    if (location != null) {
                        wayLatitude = location.getLatitude();
                        wayLongitude = location.getLongitude();
                        if (!isContinue) {
                            txtLocation.setText(String.format(Locale.US, "%s - %s", wayLatitude, wayLongitude));
                        } else {
                            stringBuilder.append(wayLatitude);
                            stringBuilder.append("-");
                            stringBuilder.append(wayLongitude);
                            stringBuilder.append("\n\n");
                            txtContinueLocation.setText(stringBuilder.toString());
                        }
                *******************************************************

                        if (!isContinue && mFusedLocationClient != null) {
                            mFusedLocationClient.removeLocationUpdates(locationCallback);
                        }
                    }
                }
            }
        };

        btnLocation.setOnClickListener(v -> {

            if (!isGPS) {
                Toast.makeText(this, "Please turn on GPS", Toast.LENGTH_SHORT).show();
                return;
            }
            isContinue = false;
            getLocation();
        });

        btnContinueLocation.setOnClickListener(v -> {
            if (!isGPS) {
                Toast.makeText(this, "Please turn on GPS", Toast.LENGTH_SHORT).show();
                return;
            }
            isContinue = true;
            stringBuilder = new StringBuilder();
            getLocation();
        });
    }

    private void getLocation() {
        if (ActivityCompat.checkSelfPermission(MainActivity.this, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED
                && ActivityCompat.checkSelfPermission(MainActivity.this, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
            ActivityCompat.requestPermissions(MainActivity.this, new String[]{Manifest.permission.ACCESS_FINE_LOCATION, Manifest.permission.ACCESS_COARSE_LOCATION},
                    AppConstants.LOCATION_REQUEST);

        } else {
            if (isContinue) {
                mFusedLocationClient.requestLocationUpdates(locationRequest, locationCallback, null);
            } else {
                mFusedLocationClient.getLastLocation().addOnSuccessListener(MainActivity.this, location -> {
                    if (location != null) {
                        wayLatitude = location.getLatitude();
                        wayLongitude = location.getLongitude();
                        txtLocation.setText(String.format(Locale.US, "%s - %s", wayLatitude, wayLongitude));
                    } else {
                        mFusedLocationClient.requestLocationUpdates(locationRequest, locationCallback, null);
                    }
                });
            }
        }
    }

    @SuppressLint("MissingPermission")
    @Override
    public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
        super.onRequestPermissionsResult(requestCode, permissions, grantResults);
        switch (requestCode) {
            case 1000: {
                // If request is cancelled, the result arrays are empty.
                if (grantResults.length > 0
                        && grantResults[0] == PackageManager.PERMISSION_GRANTED) {

                    if (isContinue) {
                        mFusedLocationClient.requestLocationUpdates(locationRequest, locationCallback, null);
                    } else {
                        mFusedLocationClient.getLastLocation().addOnSuccessListener(MainActivity.this, location -> {
                            if (location != null) {
                                wayLatitude = location.getLatitude();
                                wayLongitude = location.getLongitude();
                                txtLocation.setText(String.format(Locale.US, "%s - %s", wayLatitude, wayLongitude));
                            } else {
                                mFusedLocationClient.requestLocationUpdates(locationRequest, locationCallback, null);
                            }
                        });
                    }
                } else {
                    Toast.makeText(this, "Permission denied", Toast.LENGTH_SHORT).show();
                }
                break;
            }
        }
    }

    @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        super.onActivityResult(requestCode, resultCode, data);
        if (resultCode == Activity.RESULT_OK) {
            if (requestCode == AppConstants.GPS_REQUEST) {
                isGPS = true; // flag maintain before get location
            }
        }
    }
}

当我这样做时，代码运行良好。然后我尝试根据需要更新代码以显示当前位置的状态以及“即显示用户电话当前所在的状态（例如南卡罗来纳州、马萨诸塞州、加利福尼亚州等）。

这是更新后的代码：

package com.coders.location;

import android.Manifest;
import android.annotation.SuppressLint;
import android.app.Activity;
import android.content.Intent;
import android.content.pm.PackageManager;
import android.location.Address;
import android.location.Geocoder;
import android.location.Location;
import android.os.Bundle;
import android.support.annotation.NonNull;
import android.support.v4.app.ActivityCompat;
import android.support.v7.app.AppCompatActivity;
import android.widget.Button;
import android.widget.TextView;
import android.widget.Toast;

import com.google.android.gms.location.FusedLocationProviderClient;
import com.google.android.gms.location.LocationCallback;
import com.google.android.gms.location.LocationRequest;
import com.google.android.gms.location.LocationResult;
import com.google.android.gms.location.LocationServices;

import java.io.IOException;
import java.util.List;
import java.util.Locale;

public class MainActivity extends AppCompatActivity {

    private FusedLocationProviderClient mFusedLocationClient;

    private double wayLatitude = 0.0, wayLongitude = 0.0;
    private LocationRequest locationRequest;
    private LocationCallback locationCallback;
    private android.widget.Button btnLocation;
    private TextView txtLocation;
    private android.widget.Button btnContinueLocation;
    private TextView txtContinueLocation;
    private StringBuilder stringBuilder;

    private boolean isContinue = false;
    private boolean isGPS = false;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        this.txtContinueLocation = (TextView) findViewById(R.id.txtContinueLocation);
        this.btnContinueLocation = (Button) findViewById(R.id.btnContinueLocation);
        this.txtLocation = (TextView) findViewById(R.id.txtLocation);
        this.btnLocation = (Button) findViewById(R.id.btnLocation);

        mFusedLocationClient = LocationServices.getFusedLocationProviderClient(this);

        locationRequest = LocationRequest.create();
        locationRequest.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY);
        locationRequest.setInterval(10 * 1000); // 10 seconds
        locationRequest.setFastestInterval(5 * 1000); // 5 seconds

        new GpsUtils(this).turnGPSOn(new GpsUtils.onGpsListener() {
            @Override
            public void gpsStatus(boolean isGPSEnable) {
                // turn on GPS
                isGPS = isGPSEnable;
            }
        });

        locationCallback = new LocationCallback() {
            @Override
            public void onLocationResult(LocationResult locationResult) {
                if (locationResult == null) {
                    return;
                }
                *******************************************************
                for (Location location : locationResult.getLocations()) {
                    if (location != null) {
                        wayLatitude = location.getLatitude();
                        wayLongitude = location.getLongitude();

                        double latitude = location.getLatitude();
                        double longitude = location.getLongitude();
                        Geocoder gc = new Geocoder(getApplicationContext(), Locale.getDefault());
                        try {
                            List<Address> addresses = gc.getFromLocation(latitude, longitude, 1);

                            if (addresses.size() > 0) {
                                Address address = addresses.get(0);
                                for (int i = 0; i < address.getMaxAddressLineIndex(); i++)
                                    stringBuilder.append(address.getAddressLine(i)).append("\n");
                                stringBuilder.append(address.getLocality()).append("\n");
                                stringBuilder.append(address.getPostalCode()).append("\n");
                                stringBuilder.append(address.getCountryName());
                            }
                        } catch (IOException e){

                        }


                        if (!isContinue) {
                            txtLocation.setText(stringBuilder.toString());
                        } else {
                            stringBuilder.append(wayLatitude);
                            stringBuilder.append("-");
                            stringBuilder.append(wayLongitude);
                            stringBuilder.append("\n\n");
                            txtContinueLocation.setText(stringBuilder.toString());
                        }
                *******************************************************
                        if (!isContinue && mFusedLocationClient != null) {
                            mFusedLocationClient.removeLocationUpdates(locationCallback);
                        }
                    }
                }
            }
        };

        btnLocation.setOnClickListener(v -> {

            if (!isGPS) {
                Toast.makeText(this, "Please turn on GPS", Toast.LENGTH_SHORT).show();
                return;
            }
            isContinue = false;
            getLocation();
        });

        btnContinueLocation.setOnClickListener(v -> {
            if (!isGPS) {
                Toast.makeText(this, "Please turn on GPS", Toast.LENGTH_SHORT).show();
                return;
            }
            isContinue = true;
            stringBuilder = new StringBuilder();
            getLocation();
        });
    }

    private void getLocation() {
        if (ActivityCompat.checkSelfPermission(MainActivity.this, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED
                && ActivityCompat.checkSelfPermission(MainActivity.this, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
            ActivityCompat.requestPermissions(MainActivity.this, new String[]{Manifest.permission.ACCESS_FINE_LOCATION, Manifest.permission.ACCESS_COARSE_LOCATION},
                    AppConstants.LOCATION_REQUEST);

        } else {
            if (isContinue) {
                mFusedLocationClient.requestLocationUpdates(locationRequest, locationCallback, null);
            } else {
                mFusedLocationClient.getLastLocation().addOnSuccessListener(MainActivity.this, location -> {
                    if (location != null) {
                        wayLatitude = location.getLatitude();
                        wayLongitude = location.getLongitude();
                        txtLocation.setText(String.format(Locale.US, "%s - %s", wayLatitude, wayLongitude));
                    } else {
                        mFusedLocationClient.requestLocationUpdates(locationRequest, locationCallback, null);
                    }
                });
            }
        }
    }

    @SuppressLint("MissingPermission")
    @Override
    public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
        super.onRequestPermissionsResult(requestCode, permissions, grantResults);
        switch (requestCode) {
            case 1000: {
                // If request is cancelled, the result arrays are empty.
                if (grantResults.length > 0
                        && grantResults[0] == PackageManager.PERMISSION_GRANTED) {

                    if (isContinue) {
                        mFusedLocationClient.requestLocationUpdates(locationRequest, locationCallback, null);
                    } else {
                        mFusedLocationClient.getLastLocation().addOnSuccessListener(MainActivity.this, location -> {
                            if (location != null) {
                                wayLatitude = location.getLatitude();
                                wayLongitude = location.getLongitude();
                                txtLocation.setText(String.format(Locale.US, "%s - %s", wayLatitude, wayLongitude));
                            } else {
                                mFusedLocationClient.requestLocationUpdates(locationRequest, locationCallback, null);
                            }
                        });
                    }
                } else {
                    Toast.makeText(this, "Permission denied", Toast.LENGTH_SHORT).show();
                }
                break;
            }
        }
    }

    @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        super.onActivityResult(requestCode, resultCode, data);
        if (resultCode == Activity.RESULT_OK) {
            if (requestCode == AppConstants.GPS_REQUEST) {
                isGPS = true; // flag maintain before get location
            }
        }
    }
}

此代码现在甚至不显示当前的纬度和经度。有人可以帮我弄这个吗。我希望显示状态以及当前位置的纬度和经度。

已实施更改且似乎与我的问题最相关的代码行在代码的开头和结尾处用一长串星号标记，如下所示： ****************************************************** *****

Answer 1

我们需要做的就是在清单文件中添加这个权限：

<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />

然后像这样创建一个 LocationManager 实例：

LocationManager locationManager = (LocationManager)
getSystemService(Context.LOCATION_SERVICE);
Check if GPS is enabled or not.

然后实现LocationListener并获取坐标：

LocationListener locationListener = new MyLocationListener();
locationManager.requestLocationUpdates(
LocationManager.GPS_PROVIDER, 5000, 10, locationListener);
Here is the sample code to do so

私有类 MyLocationListener 实现 LocationListener {

    @Override
    public void onLocationChanged(Location loc) {
        editLocation.setText("");
        pb.setVisibility(View.INVISIBLE);
        Toast.makeText(
                getBaseContext(),
                "Location changed: Lat: " + loc.getLatitude() + " Lng: "
                    + loc.getLongitude(), Toast.LENGTH_SHORT).show();
        String longitude = "Longitude: " + loc.getLongitude();
        Log.v(TAG, longitude);
        String latitude = "Latitude: " + loc.getLatitude();
        Log.v(TAG, latitude);

        /*------- To get city name from coordinates -------- */
        String cityName = null;
        Geocoder gcd = new Geocoder(getBaseContext(), Locale.getDefault());
        List<Address> addresses;
        try {
            addresses = gcd.getFromLocation(loc.getLatitude(),
                    loc.getLongitude(), 1);
            if (addresses.size() > 0) {
                System.out.println(addresses.get(0).getLocality());
                cityName = addresses.get(0).getLocality();
            }
        }
        catch (IOException e) {
            e.printStackTrace();
        }
        String s = longitude + "\n" + latitude + "\n\nMy Current City is: "
            + cityName;
        editLocation.setText(s);
    }

    @Override
    public void onProviderDisabled(String provider) {}

    @Override
    public void onProviderEnabled(String provider) {}

    @Override
    public void onStatusChanged(String provider, int status, Bundle extras) {}
}

查看此流程： How do I get the current GPS location programmatically in Android?

Answer 2

实际上这段代码现在不起作用。 Google 已弃用上述代码，现在您需要使用以下代码。

我使用了改造 改造客户端

public static final String GOOGLE_ETA = "https://maps.googleapis.com/maps/";

public static Retrofit getEtaClient() {
    if (retrofitEtaGoogle == null) {
        retrofitEtaGoogle = new Retrofit.Builder()
                .baseUrl(GOOGLE_ETA)
                .client(provideOkHttpClient())
                .addConverterFactory(GsonConverterFactory.create())
                .build();
    }
    return retrofitEtaGoogle;
}

API接口类

@GET("api/geocode/json?key="+ Consts.GOOGLE_API_KEY)
Call<GoogleGeoCodeApiResponseModel> getPlaceFromLatLng(@Query("latlng") String latLng);

在 updateLocationUI() 方法中

String latLng = location.getLatitude() + "," + location.getLongitude();
    ApiInterface apiInterface = RetrofitClient.getEtaClient().create(ApiInterface.class);
    Call<GoogleGeoCodeApiResponseModel> call = apiInterface.getPlaceFromLatLng(latLng);
    call.enqueue(new Callback<GoogleGeoCodeApiResponseModel>() {
        @Override
        public void onResponse(Call<GoogleGeoCodeApiResponseModel> call, Response<GoogleGeoCodeApiResponseModel> response) {

            if (response.body().getStatus() != null && response.body().getStatus().equals("OK")) {
                addressObj = new GoogleAddressLocalModel();
                addressObj.setName(response.body().getResults().get(0).getFormattedAddress());
                addressObj.setLat(response.body().getResults().get(0).getGeometry().getLocation().getLat());
                addressObj.setLng(response.body().getResults().get(0).getGeometry().getLocation().getLng());
                for (GoogleGeoCodeApiResponseModel.AddressComponent obj : response.body().getResults().get(0).getAddressComponents()) {
                    for (String type : obj.getTypes()) {
                        if (type.contains("postal_code")) {
                            addressObj.setPostalCode(obj.getLongName());
                        } else if (type.contains("country")) {
                            addressObj.setCountryId(obj.getShortName());
                            addressObj.setCountryName(obj.getLongName());
                        } else if (type.contains("administrative_area_level_2")) {
                            addressObj.setCityName(obj.getLongName());
                        }
                    }
                }


            } else if (response.body().getStatus() != null) {
                Log.e("ErrroGettingAddress", response.body().getStatus());

            }
        }

        @Override
        public void onFailure(Call<GoogleGeoCodeApiResponseModel> call, Throwable t) {
            Log.e("ErrroGettingAddress", t.getLocalizedMessage());

        }
    });
}