快速获取当前位置一次 android

get the current location fast and once in android

我有一个 android 应用程序需要设备当前位置(纬度和经度)。我已经在网上尝试了一些教程,特别是一些来自堆栈溢出的解决方案,但它们对我来说效果不佳。我的要求很简单:首先我需要它快,并且在片段开始时需要一次位置。其次我需要它尽可能精确,我的意思是它应该首先使用 GPS 如果 GPS 不可用然后使用网络提供商。

例如,我试过 this solution 但 30 秒后它 return 为空,但我知道有一些一切正常,因为 google 地图和其他应用程序效果不错!!!

几乎所有答案都建议使用 getLastKnownLocation(),但我想它不是当前的,如果是这样的话我不想要它。

任何人都可以建议我一些简单快速的方法来一次获取位置吗?!

你想做的是使用 LocationManager#requestSingleUpdate 实现的。此方法在给定的循环器中附加一个侦听器(如果您想要或拥有它)并尽快通知接收到的位置,仅一次。你建议的方法只是作为一个不准确的位置,才给你真正的方法。

在任何情况下,它都将比毫秒快(除非您足够幸运,可以在设备到达某个位置时开始收听)。将 GPS 视为您在等待位置时启用并在您删除此侦听时禁用的元素。这样做是为了避免耗尽用户的电池。

所以,总结一下:

  • 从开始收听到接收位置之间的时间取决于设备的 GPS(制造商、用户位置、卫星覆盖范围...)
  • Android SDK 中有一个方法可以监听单个更新。
  • 通过提供标准对象,您可以管理您可以接受哪些标准来接收位置。更强的标准意味着更多的时间来获得准确的响应。

在这里,你可以使用这个...

用法示例:

public void foo(Context context) {
  // when you need location
  // if inside activity context = this;

  SingleShotLocationProvider.requestSingleUpdate(context, 
   new SingleShotLocationProvider.LocationCallback() {
     @Override public void onNewLocationAvailable(GPSCoordinates location) {
       Log.d("Location", "my location is " + location.toString());
     }
   });
}

您可能想要验证 lat/long 是实际值而不是 0 或其他值。如果我没记错的话,这不应该引发 NPE,但您可能想要验证这一点。

public class SingleShotLocationProvider {

  public static interface LocationCallback {
      public void onNewLocationAvailable(GPSCoordinates location);
  }

  // calls back to calling thread, note this is for low grain: if you want higher precision, swap the 
  // contents of the else and if. Also be sure to check gps permission/settings are allowed.
  // call usually takes <10ms
  public static void requestSingleUpdate(final Context context, final LocationCallback callback) {
      final LocationManager locationManager = (LocationManager) context.getSystemService(Context.LOCATION_SERVICE);
      boolean isNetworkEnabled = locationManager.isProviderEnabled(LocationManager.NETWORK_PROVIDER);
      if (isNetworkEnabled) {
          Criteria criteria = new Criteria();
          criteria.setAccuracy(Criteria.ACCURACY_COARSE);
          locationManager.requestSingleUpdate(criteria, new LocationListener() {
              @Override
              public void onLocationChanged(Location location) {
                  callback.onNewLocationAvailable(new GPSCoordinates(location.getLatitude(), location.getLongitude()));
              }

              @Override public void onStatusChanged(String provider, int status, Bundle extras) { }
              @Override public void onProviderEnabled(String provider) { }
              @Override public void onProviderDisabled(String provider) { }
          }, null);
      } else {
          boolean isGPSEnabled = locationManager.isProviderEnabled(LocationManager.GPS_PROVIDER);
          if (isGPSEnabled) {
              Criteria criteria = new Criteria();
              criteria.setAccuracy(Criteria.ACCURACY_FINE);
              locationManager.requestSingleUpdate(criteria, new LocationListener() {
                  @Override
                  public void onLocationChanged(Location location) {
                      callback.onNewLocationAvailable(new GPSCoordinates(location.getLatitude(), location.getLongitude()));
                  }

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


  // consider returning Location instead of this dummy wrapper class
  public static class GPSCoordinates {
      public float longitude = -1;
      public float latitude = -1;

      public GPSCoordinates(float theLatitude, float theLongitude) {
          longitude = theLongitude;
          latitude = theLatitude;
      }

      public GPSCoordinates(double theLatitude, double theLongitude) {
          longitude = (float) theLongitude;
          latitude = (float) theLatitude;
      }
  }  
}
    // Get LocationManager object
    LocationManager locationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);

    // Create a criteria object to retrieve provider
    Criteria criteria = new Criteria();

    // Get the name of the best provider
    String provider = locationManager.getBestProvider(criteria, true);

    // Get Current Location
    Location myLocation = locationManager.getLastKnownLocation(provider);

    //latitude of location
    double myLatitude = myLocation.getLatitude();

    //longitude og location
    double myLongitude = myLocation.getLongitude();

    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;
    }

AndroidManifest.xml:

<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
<uses-feature android:name="android.hardware.location.gps" />

MainActivity.java:

public class MainActivity extends AppCompatActivity implements LocationListener {

    private LocationManager locationManager;
    private Location onlyOneLocation;
    private final int REQUEST_FINE_LOCATION = 1234;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        if (ContextCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED)
            ActivityCompat.requestPermissions(this, new String[] {Manifest.permission.ACCESS_FINE_LOCATION}, REQUEST_FINE_LOCATION);
    }

    @Override public void onLocationChanged(Location location) {
        onlyOneLocation = location;
        locationManager.removeUpdates(this);
    }
    @Override public void onStatusChanged(String provider, int status, Bundle extras) { }
    @Override public void onProviderEnabled(String provider) { }
    @Override public void onProviderDisabled(String provider) { }

    @Override
    public void onRequestPermissionsResult(int requestCode, String permissions[], int[] grantResults) {
        switch (requestCode) {
        case REQUEST_FINE_LOCATION:
            if (grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
                Log.d("gps", "Location permission granted");
                try {
                    locationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
                    locationManager.requestLocationUpdates("gps", 0, 0, this);
                }
                catch (SecurityException ex) {
                    Log.d("gps", "Location permission did not work!");
                }
            }
            break;
    }
}

AndroidManifest.xml

<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
<uses-feature android:name="android.hardware.location.gps" />

Requesting User Permissions


build.gradle(模块:app)

dependencies {
    ...
    implementation 'com.google.android.gms:play-services-location:15.0.0'
    ...
}

If you receive an error, check that your top-level build.gradle contains a reference to the google() repo or to maven { url "https://maven.google.com" }

Set Up Google Play Services


LocationService.kt

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.net.Uri
import android.os.Looper
import android.provider.Settings
import android.support.v4.app.ActivityCompat
import android.support.v4.content.ContextCompat
import com.google.android.gms.common.api.ApiException
import com.google.android.gms.common.api.ResolvableApiException
import com.google.android.gms.location.*
import org.jetbrains.anko.alert
import org.jetbrains.anko.doAsync
import org.jetbrains.anko.okButton

object LocationService {

    @SuppressLint("StaticFieldLeak")
    private lateinit var fusedLocationProviderClient: FusedLocationProviderClient
    private lateinit var locationRequest: LocationRequest
    private val locationCallback = object : LocationCallback() {
        override fun onLocationResult(locationResult: LocationResult) {
            doAsync {
                location = locationResult.lastLocation
                onSuccess(location)
            }
        }
    }
    private lateinit var onSuccess: (location : Location) -> Unit
    private lateinit var onError: () -> Unit
    lateinit var location: Location

    fun init(activity: Activity) {
        fusedLocationProviderClient = FusedLocationProviderClient(activity)
        locationRequest = LocationRequest().setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY).setInterval(1000).setFastestInterval(1000).setNumUpdates(1)
    }

    private fun checkLocationStatusAndGetLocation(activity: Activity) {
        doAsync {
            when {
                ContextCompat.checkSelfPermission(activity, Manifest.permission.ACCESS_FINE_LOCATION) == PackageManager.PERMISSION_GRANTED -> LocationServices.getSettingsClient(activity).checkLocationSettings(LocationSettingsRequest.Builder().addLocationRequest(locationRequest).setAlwaysShow(true).build()).addOnCompleteListener { task ->
                    doAsync {
                        try {
                            task.getResult(ApiException::class.java)
                            fusedLocationProviderClient.requestLocationUpdates(locationRequest, locationCallback, Looper.getMainLooper())
                        } catch (exception: ApiException) {
                            when (exception.statusCode) {
                                LocationSettingsStatusCodes.RESOLUTION_REQUIRED -> {
                                    try {
                                        (exception as ResolvableApiException).startResolutionForResult(activity, 7025)
                                    } catch (ex: Exception) {
                                        promptShowLocation(activity)
                                    }
                                }
                                LocationSettingsStatusCodes.SETTINGS_CHANGE_UNAVAILABLE -> {
                                    promptShowLocation(activity)
                                }
                            }
                        }
                    }
                }
                ActivityCompat.shouldShowRequestPermissionRationale(activity, Manifest.permission.ACCESS_FINE_LOCATION) -> activity.runOnUiThread {
                    activity.alert("To continue, allow the device to use location, witch uses Google's Location Service") {
                        okButton {
                            val ite = Intent(Settings.ACTION_APPLICATION_DETAILS_SETTINGS, Uri.fromParts("package", activity.packageName, null))
                            ite.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK)
                            activity.startActivity(ite)
                            onError()
                        }
                        negativeButton("Cancelar", { onError() })
                        onCancelled { onError() }
                    }.show()
                }
                else -> ActivityCompat.requestPermissions(activity, arrayOf(Manifest.permission.ACCESS_FINE_LOCATION), 7024)
            }
        }
    }

    private fun promptShowLocation(activity: Activity) {
        activity.runOnUiThread {
            activity.alert("To continue, allow the device to use location, witch uses Google's Location Service") {
                okButton {
                    activity.startActivity(Intent(Settings.ACTION_LOCATION_SOURCE_SETTINGS))
                    onError()
                }
                negativeButton("Cancelar", { onError() })
                onCancelled { onError() }
            }.show()
        }
    }

    fun onRequestPermissionsResult(activity: Activity, requestCode: Int, grantResults: IntArray) {
        if (requestCode == 7024) {
            if (grantResults.isNotEmpty() && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
                checkLocationStatusAndGetLocation(activity)
            } else {
                onError()
            }
        }
    }

    fun onActivityResult(activity: Activity, requestCode: Int, resultCode: Int) {
        if (requestCode == 7025) {
            if (resultCode == Activity.RESULT_OK) {
                checkLocationStatusAndGetLocation(activity)
            } else {
                onError()
            }
        }
    }

    fun getLocation(activity: Activity, onSuccess: () -> Unit, onError: () -> Unit) {
        this.onSuccess = onSuccess
        this.onError = onError
        checkLocationStatusAndGetLocation(activity)
    }

}

你的activity

override fun onCreate(savedInstanceState: Bundle?) {
    ...
    LocationService.init(this)
}

override fun onRequestPermissionsResult(requestCode: Int, permissions: Array<String>, grantResults: IntArray) {
    super.onRequestPermissionsResult(requestCode, permissions, grantResults)
    LocationService.onRequestPermissionsResult(this, requestCode, grantResults)
}

override fun onActivityResult(requestCode: Int, resultCode: Int, data: Intent?) {
    super.onActivityResult(requestCode, resultCode, data)
    LocationService.onActivityResult(this, requestCode, resultCode)
}

private fun yourFunction() {
    LocationService.getLocation(this, { location ->
        //TODO: use the location
    }, {
        //TODO: display error message
    })
}

以上所有答案都不适合我所以我回答了这个 最初添加依赖项

<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
<uses-feature android:name="android.hardware.location.gps" />

在添加 class MyLocationListiner.java

之后
package com.example.firebase_auth;

/**
 * Created by Chromicle(Ajay Prabhakar).
 */

import android.content.Context;
import android.content.pm.PackageManager;
import android.location.Location;
import android.location.LocationListener;
import android.location.LocationManager;
import android.os.Build;
import android.os.Bundle;
import android.widget.Toast;

import androidx.annotation.Nullable;
import androidx.core.content.ContextCompat;

import static android.content.Context.LOCATION_SERVICE;

public class MyLocationListener implements LocationListener {

    public static double latitude;
    Context ctx;
    Location location;
    LocationManager locationManager;
    boolean isGPSEnabled = false;
    boolean isNetworkEnabled = false;
    public static double longitude;
    MyLocationListener(Context ctx) {
        this.ctx = ctx;
        try {
            locationManager = (LocationManager) ctx.getSystemService(LOCATION_SERVICE);
            isGPSEnabled = locationManager.isProviderEnabled(LocationManager.GPS_PROVIDER);
            Toast.makeText(ctx, "GPS Enable " + isGPSEnabled, Toast.LENGTH_LONG).show();
            isNetworkEnabled = locationManager.isProviderEnabled(LocationManager.NETWORK_PROVIDER);
            Toast.makeText(ctx, "Network Enable " + isNetworkEnabled, Toast.LENGTH_LONG).show();

            if ( Build.VERSION.SDK_INT >= 23 && ContextCompat.checkSelfPermission
                    ( ctx, android.Manifest.permission.ACCESS_FINE_LOCATION )
                    != PackageManager.PERMISSION_GRANTED &&
                    ContextCompat.checkSelfPermission( ctx,
                            android.Manifest.permission.ACCESS_COARSE_LOCATION) !=
                            PackageManager.PERMISSION_GRANTED) {  }
            if (isGPSEnabled == true) {
                locationManager.requestLocationUpdates(
                        LocationManager.GPS_PROVIDER,     0,       0, this);
                location = locationManager.getLastKnownLocation(LocationManager.GPS_PROVIDER);
            }
            if (isNetworkEnabled==true) {
                locationManager.requestLocationUpdates(
                        LocationManager.NETWORK_PROVIDER,    0,     0, this);
                location = locationManager.getLastKnownLocation(LocationManager.NETWORK_PROVIDER);
            }
            latitude = location.getLatitude();
            longitude = location.getLongitude();
            // Toast.makeText(ctx,"latitude: "+latitude+" longitude: "+longitude,Toast.LENGTH_LONG).show();


        }
        catch(Exception ex)
        {

            Toast.makeText(ctx,"Exception "+ex, Toast.LENGTH_LONG).show();
        }
    }
    @Nullable
    @Override
    public void onLocationChanged(Location loc)
    {
        loc.getLatitude();
        loc.getLongitude();
        latitude=loc.getLatitude();
        longitude=loc.getLongitude();
    }

    @Override
    public void onProviderDisabled(String provider)
    {
        //print "Currently GPS is Disabled";
    }
    @Override
    public void onProviderEnabled(String provider)
    {
        //print "GPS got Enabled";
    }
    @Override
    public void onStatusChanged(String provider, int status, Bundle extras)
    {

    }
}

要使用 class 添加此方法 位置存储在地址字符串中

public void getLocation(){
        Double latitude = 0.0, longitude;
        String message = "";
        LocationManager mlocManager = null;
        LocationListener mlocListener;
        mlocManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
        mlocListener = new MyLocationListener(this);
        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;
        }
        mlocManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, 0, 0, mlocListener);
        if (mlocManager.isProviderEnabled(LocationManager.GPS_PROVIDER)) {

            latitude = MyLocationListener.latitude;
            longitude = MyLocationListener.longitude;
            message = message +"https://www.google.com/maps/dir/@"+ latitude +","+  longitude;
            address=message;
            Toast.makeText(getApplicationContext(), message, Toast.LENGTH_LONG).show();
            if (latitude == 0.0) {
                Toast.makeText(getApplicationContext(), "Currently gps has not found your location....", Toast.LENGTH_LONG).show();
            }

        } else {
            Toast.makeText(getApplicationContext(), "GPS is currently off...", Toast.LENGTH_LONG).show();
        }
    }

希望对您有所帮助

我创建了一些 classes 使用那些你可以很容易地得到当前位置。我使用 FusedLocationProviderClient 获取当前位置。

首先将其添加到您的清单文件中:

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

然后检查位置权限:

 private fun startCheckingLocation() {
    if (checkLocationPermissions() == true) {
        checkGPSEnabled()
    } else {
        askLocationPermission()
    }
}

checkLocationPermissions 方法:

 private fun checkLocationPermissions(): Boolean? {
    return PermissionUtils.hasPermissions(
        requireContext(),
        Manifest.permission.ACCESS_FINE_LOCATION,
        Manifest.permission.ACCESS_COARSE_LOCATION
    )
}

检查 GPSEnabled 方法:

 private fun checkGPSEnabled() {
    GpsUtils(requireContext()) {
        it?.let {
            startCheckingCurrentLocation()
        }
    }.apply {
        turnGPSOn(gpsDialogCallback)
    }
}

由于 OnActivityResult 已弃用:

     private val gpsDialogCallback =     registerForActivityResult(ActivityResultContracts.StartIntentSenderForResult()) { activityResult ->
        activityResult?.let { result ->
            when (result.resultCode) {
                RESULT_OK -> {
                    startCheckingCurrentLocation()
                }
                RESULT_CANCELED -> {
                }
            }
        }
    }

startCheckingCurrentLocation 方法:

 private fun startCheckingCurrentLocation() {
    LocationUtils(requireContext()) { location ->
        Log.d(TAG, ">>>>>>>>>>>>>>" + location.latitude + " " + location.longitude)
        startIntentService(location)
    }.apply {
        startLocationUpdates()
    }
}

对于 GPS,我创建了一个 class,您可以简单地放置和使用它:

GPSUtils:

class GpsUtils(
private val context: Context,
private val gpsStatus: (isEnable: Boolean?) -> Unit
) {

private val mSettingsClient: SettingsClient = LocationServices.getSettingsClient(context)
private val mLocationSettingsRequest: LocationSettingsRequest
private val locationManager: LocationManager =
    context.getSystemService(Context.LOCATION_SERVICE) as LocationManager
private val locationRequest: LocationRequest = LocationRequest.create()

init {
    locationRequest.priority = LocationRequest.PRIORITY_HIGH_ACCURACY
    locationRequest.interval = 10 * 1000.toLong()
    locationRequest.fastestInterval = 2 * 1000.toLong()
    val builder = LocationSettingsRequest.Builder().addLocationRequest(locationRequest)
    mLocationSettingsRequest = builder.build()
    builder.setAlwaysShow(true) //this is the key ingredient
}

// method for turn on GPS
fun turnGPSOn(gpsDialogCallback: ActivityResultLauncher<IntentSenderRequest>) {
    if (locationManager.isProviderEnabled(LocationManager.GPS_PROVIDER)) {
        gpsStatus.invoke(true)
    } else {
        mSettingsClient
            .checkLocationSettings(mLocationSettingsRequest)
            .addOnSuccessListener(
                (context as Activity)
            ) {
                //  GPS is already enable, callback GPS status through listener
                gpsStatus.invoke(true)
            }
            .addOnFailureListener(context) { e ->
                when ((e as ApiException).statusCode) {
                    LocationSettingsStatusCodes.RESOLUTION_REQUIRED -> try {
                        // Show the dialog by calling startResolutionForResult() and check the result in onActivityResult().

                        if (e is ResolvableApiException) {
                            try {
                                val intentSenderRequest = IntentSenderRequest.Builder(e.resolution).build()
                                gpsDialogCallback.launch(intentSenderRequest)
                            } catch (throwable: Throwable) {
                                // Ignore the error.
                            }
                        }

                    } catch (sie: IntentSender.SendIntentException) {
                        // Ignore the error.
                        Timber.i("PendingIntent unable to execute request.")
                    }
                    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.
                        val errorMessage =
                            "Location settings are inadequate, and cannot be fixed here. Fix in Settings."
                        Timber.e(errorMessage)
                    }
                    LocationSettingsStatusCodes.CANCELED -> {
                        val errorMessage =
                            "Location settings are inadequate, and cannot be fixed here. Fix in Settings."
                        Timber.e(errorMessage)
                    }
                    LocationSettingsStatusCodes.SUCCESS -> {
                        // All location settings are satisfied. The client can initialize location
                        // requests here.
                        val errorMessage =
                            "Location settings are inadequate, and cannot be fixed here. Fix in Settings."
                        Timber.e(errorMessage)
                    }
                }
            }
    }
}

}

为了检查位置,我又创建了一个 class :

class LocationUtils(
context: Context,
private val latLng: (location: Location) -> Unit) {

private var fusedLocationClient: FusedLocationProviderClient? = null

private val locationRequest = LocationRequest.create()?.apply {
    interval = 20 * 1000.toLong()
    fastestInterval = 2 * 1000.toLong()
    priority = LocationRequest.PRIORITY_HIGH_ACCURACY
}


init {
    fusedLocationClient = LocationServices.getFusedLocationProviderClient(context)
}

/**
 * call when location permission is allowed and you want to fetch the last location of the user
 */
fun getLastLocation() {
    fusedLocationClient?.lastLocation?.addOnSuccessListener { location ->
        location?.let {
            latLng.invoke(location)
            stopLocationUpdates()
        }
    }
}

/**
 * Requested location callback
 */
private val locationCallback = object : LocationCallback() {
    override fun onLocationResult(locationResult: LocationResult?) {

        locationResult ?: return

        for (location in locationResult.locations) {
            location?.let {
                latLng.invoke(it)
                stopLocationUpdates()
            }
        }
        super.onLocationResult(locationResult)
    }
}

/**
 * call when location permission is already given to user and you want to receive continues location updates
 */
fun startLocationUpdates() {
    fusedLocationClient?.requestLocationUpdates(
        locationRequest,
        locationCallback,
        Looper.getMainLooper()
    )
}

/**
 * call when you want to stop location updates
 */
fun stopLocationUpdates() {
    fusedLocationClient?.removeLocationUpdates(locationCallback)?.addOnCompleteListener { }
}


}

我创建了一个工人 class 从 latlng 获取地址:

class FetchAddressWorker(
context: Context,
workerParameters: WorkerParameters
) :
Worker(context, workerParameters) {

companion object {
    const val TAG = "FetchAddressWorker"
}

override fun doWork(): Result {

    val geoCoder = Geocoder(applicationContext, Locale.getDefault())

    var errorMessage = ""

    val lat: Double = inputData.getDouble(CPKConstants.LATITUDE, 0.0)
    val lng: Double = inputData.getDouble(CPKConstants.LONGITUDE, 0.0)

    var addresses: List<Address> = emptyList()

    try {
        addresses =
            geoCoder.getFromLocation(lat, lng, 1)
    } catch (ioException: IOException) {
        // Catch network or other I/O problems.
        errorMessage = "Service not available"
        LogUtils.e(TAG, errorMessage, ioException)
    } catch (illegalArgumentException: IllegalArgumentException) {
        // Catch invalid latitude or longitude values.
        errorMessage = "Invalid lat lng used"
        LogUtils.e(
            TAG,
            "$errorMessage. Latitude = $lat , Longitude =  $lng",
            illegalArgumentException
        )
    }

    // Handle case where no address was found.
    if (addresses.isEmpty()) {
        if (errorMessage.isEmpty()) {
            errorMessage = "No Address Found"
            LogUtils.e(TAG, errorMessage)
        }

        val data = Data.Builder()
            .putString(
                CPKConstants.FAILURE_RESULT,
                errorMessage
            )
            .build()

        return Result.failure(data)
    } else {
        val address: Address = addresses[0]
        // Fetch the address lines using getAddressLine,
        // join them, and send them to the thread.
        val addressFragments = with(address) {
            (0..maxAddressLineIndex).map { getAddressLine(it) }
        }
        LogUtils.i(TAG, "Address Found " + addressFragments.joinToString(separator = "\n"))
        
       
        val data = Data.Builder()
            .putString(
                CPKConstants.SUCCESS_RESULT,
                addressFragments.joinToString(separator = "\n")
            )
            .build()
        // Indicate whether the work finished successfully with the Result
        return Result.success(data)
    }

}

}

比在片段中使用 AddressResultReceiver 或者 activity:

 internal inner class AddressResultReceiver(handler: Handler) : ResultReceiver(handler) {

    override fun onReceiveResult(resultCode: Int, resultData: Bundle?) {

        // Display the address string
        // or an error message sent from the intent service.
        val addressOutput = resultData?.getString(AppConstants.RESULT_DATA_KEY).orEmpty()
        //displayAddressOutput()
        // Show a toast message if an address was found.
        if (resultCode == AppConstants.SUCCESS_RESULT) {
            Boast.showText(requireContext(), "Address found = $addressOutput")
            txtContinueWith.text = addressOutput
        }

    }
}

您需要在片段或 activity 中初始化它,您将在其中使用上述接收器获取地址:

  private var resultReceiver = AddressResultReceiver(Handler())

这些是您应该按原样使用的一些常量。

//Location Constants
const val LOCATION_SERVICE = "LOCATION_SERVICE"
const val SUCCESS_RESULT = 0
const val FAILURE_RESULT = 1
const val PACKAGE_NAME = "com.google.android.gms.location.sample.locationaddress"
const val RECEIVER = "$PACKAGE_NAME.RECEIVER"
const val RESULT_DATA_KEY = "${PACKAGE_NAME}.RESULT_DATA_KEY"
const val LOCATION_DATA_EXTRA = "${PACKAGE_NAME}.LOCATION_DATA_EXTRA"

从视图启动工作器

  private fun startAddressWorkManager(location: Location) {

    val inputData = Data.Builder()
        .putDouble(CPKConstants.LATITUDE, location.latitude)
        .putDouble(CPKConstants.LONGITUDE, location.longitude)
        .build()

    val constraints = Constraints.Builder()
        .setRequiredNetworkType(NetworkType.CONNECTED)
        .build()

    val fetchAddressWorkRequest: WorkRequest =
        OneTimeWorkRequestBuilder<FetchAddressWorker>()
            .setConstraints(constraints)
            .setInputData(inputData)
            .build()

    WorkManager
        .getInstance(this)
        .enqueue(fetchAddressWorkRequest)

    WorkManager.getInstance(this).getWorkInfoByIdLiveData(fetchAddressWorkRequest.id)
        .observe(this,
            { workInfo ->
                when (workInfo.state) {
                    WorkInfo.State.SUCCEEDED -> {
                        if (workInfo.state.isFinished) {
                            val addressData =
                                workInfo.outputData.getString(CPKConstants.SUCCESS_RESULT)
                            Timber.d("AddressData %s", addressData)
                            _binding?.searchEdt?.setText(addressData)
                        }
                    }
                    else -> {
                        Timber.d("workInfo %s", workInfo)
                    }
                }
            })

}

对于任何有兴趣以最好的、惯用的方式、使用最新的 API 和 Kotlin 的魔力检索单个位置更新的人,这里是:

Gradle依赖性:

dependencies {
    ...
    implementation "com.google.android.gms:play-services-location:18.0.0"
    ...
}

清单权限:

<manifest>
    ...
    <!-- required only for LocationRequest.PRIORITY_HIGH_ACCURACY -->
    <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION"/> 
    <!-- required for all other priorities -->
    <uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION"/>
    ...
</manifest>

你的 Extensions 文件中的某处:

// To use PRIORITY_HIGH_ACCURACY, you must have ACCESS_FINE_LOCATION permission.
// Any other priority will require just ACCESS_COARSE_LOCATION,
// but will not guarantee a location update
@SuppressLint("MissingPermission")
suspend fun FusedLocationProviderClient.awaitCurrentLocation(priority: Int): Location? {
    return suspendCancellableCoroutine {
        // to use for request cancellation upon coroutine cancellation
        val cts = CancellationTokenSource()
        getCurrentLocation(priority, cts.token)
            .addOnSuccessListener {location ->
                // remember location is nullable, this happens sometimes
                // when the request expires before an update is acquired
                it.resume(location)
            }.addOnFailureListener {e ->
                it.resumeWithException(e)
            }

        it.invokeOnCancellation {
            cts.cancel()
        }
    }
}

在你的片段中:

// need to register this anywhere before onCreateView, idealy as a field
private val permissionRequester = registerForActivityResult(
    // you can use RequestPermission() contract if you only need 1 permission
    ActivityResultContracts.RequestMultiplePermissions()
) { map ->
    // If you requested 1 permission, change `map` to `isGranted`
    // Keys are permissions Strings, values are isGranted Booleans
    // An easy way to check if "any" permission was granted is map.containsValue(true)
    // You can use your own logic for multiple permissions, 
    // but they have to follow the same checks here:
    val response = map.entries.first()
    val permission = response.key
    val isGranted = response.value
    when {
        isGranted -> onPermissionGranted()
        ActivityCompat.shouldShowRequestPermissionRationale(requireContext(), permission) -> {
            // permission denied but not permanently, tell user why you need it. 
            // Idealy provide a button to request it again and another to dismiss
            AlertDialog.Builder(requireContext())
                .setTitle(R.string.perm_request_rationale_title)
                .setMessage(R.string.perm_request_rationale)
                .setPositiveButton(R.string.request_perm_again) { _, _ -> 
                     requirePermission() 
                }
                .setNegativeButton(R.string.dismiss, null)
                .create()
                .show()
        } 
        else -> {
            // permission permanently denied
            // 1) tell user the app won't work as expected, or
            // 2) take him to your app's info screen to manually change permissions, or
            // 3) silently and gracefully degrade user experience
            // I'll leave the implementation to you
        }
    }
}

onPermissionGranted 函数:

private fun onPermissionGranted() {
    val lm = requireContext().getSystemService(Context.LOCATION_SERVICE) as LocationManager
    if(LocationManagerCompat.isLocationEnabled(lm)) {
        // you can do this your own way, eg. from a viewModel
        // but here is where you wanna start the coroutine.
        // Choose your priority based on the permission you required
        val priority = LocationRequest.PRIORITY_HIGH_ACCURACY
        lifecycleScope.launch {
            val location = LocationServices
                .getFusedLocationProviderClient(requireContext())
                .awaitCurrentLocation(priority)
            // do whatever with this location, notice that it's nullable
        }
    } else {
        // prompt user to enable location or launch location settings check
    }
}

现在您所要做的就是将此添加到 MyLocation 按钮点击侦听器:

private fun requirePermission() {
    val permissions = arrayOf(
        Manifest.permission.ACCESS_FINE_LOCATION,
        // optional: Manifest.permission.ACCESS_COARSE_LOCATION
    )
    permissionRequester.launch(permissions)
}

请注意,这具有检查权限是否已隐式授予的优点,如果是,则不显示 dialog/request。 因此,始终通过启动请求程序来启动您的流程,并且只在其回调中进行检查。