我需要以编程方式使用 GPS 获取我的当前位置。我怎样才能实现它?
23 回答
我创建了一个带有分步描述的小应用程序来获取当前位置的 GPS 坐标。
完整的示例源代码在Get Current Location coordinates, City name-in Android 中。
看看它怎么运作:
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" />
并像这样创建一个 LocationManager 实例:
LocationManager locationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
检查是否启用了 GPS。
然后实现 LocationListener 并获取坐标:
LocationListener locationListener = new MyLocationListener(); locationManager.requestLocationUpdates( LocationManager.GPS_PROVIDER, 5000, 10, locationListener);
这是执行此操作的示例代码
/*---------- Listener class to get coordinates ------------- */
private class MyLocationListener implements 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) {}
}
这是其他答案的附加信息。
由于安卓有
GPS_PROVIDER and NETWORK_PROVIDER
您可以同时注册两个并开始onLocationChanged(Location location)
从两个中获取事件。到目前为止,一切都很好。现在的问题是我们需要两个结果还是我们应该采取最好的。据我所知GPS_PROVIDER
,结果比NETWORK_PROVIDER
.
让我们定义Location
字段:
private Location currentBestLocation = null;
在我们开始监听位置变化之前,我们将实现以下方法。此方法返回 GPS 和网络之间的最后一个已知位置。对于这种方法,更新的最好。
/**
* @return the last know best location
*/
private Location getLastBestLocation() {
Location locationGPS = mLocationManager.getLastKnownLocation(LocationManager.GPS_PROVIDER);
Location locationNet = mLocationManager.getLastKnownLocation(LocationManager.NETWORK_PROVIDER);
long GPSLocationTime = 0;
if (null != locationGPS) { GPSLocationTime = locationGPS.getTime(); }
long NetLocationTime = 0;
if (null != locationNet) {
NetLocationTime = locationNet.getTime();
}
if ( 0 < GPSLocationTime - NetLocationTime ) {
return locationGPS;
}
else {
return locationNet;
}
}
每次我们检索一个新位置时,我们都会将其与之前的结果进行比较。
...
static final int TWO_MINUTES = 1000 * 60 * 2;
...
我添加了一个新方法onLocationChanged
:
@Override
public void onLocationChanged(Location location) {
makeUseOfNewLocation(location);
if(currentBestLocation == null){
currentBestLocation = location;
}
....
}
/**
* This method modify the last know good location according to the arguments.
*
* @param location The possible new location.
*/
void makeUseOfNewLocation(Location location) {
if ( isBetterLocation(location, currentBestLocation) ) {
currentBestLocation = location;
}
}
....
/** Determines whether one location reading is better than the current location fix
* @param location The new location that you want to evaluate
* @param currentBestLocation The current location fix, to which you want to compare the new one.
*/
protected boolean isBetterLocation(Location location, Location currentBestLocation) {
if (currentBestLocation == null) {
// A new location is always better than no location
return true;
}
// Check whether the new location fix is newer or older
long timeDelta = location.getTime() - currentBestLocation.getTime();
boolean isSignificantlyNewer = timeDelta > TWO_MINUTES;
boolean isSignificantlyOlder = timeDelta < -TWO_MINUTES;
boolean isNewer = timeDelta > 0;
// If it's been more than two minutes since the current location, use the new location,
// because the user has likely moved.
if (isSignificantlyNewer) {
return true;
// If the new location is more than two minutes older, it must be worse.
} else if (isSignificantlyOlder) {
return false;
}
// Check whether the new location fix is more or less accurate
int accuracyDelta = (int) (location.getAccuracy() - currentBestLocation.getAccuracy());
boolean isLessAccurate = accuracyDelta > 0;
boolean isMoreAccurate = accuracyDelta < 0;
boolean isSignificantlyLessAccurate = accuracyDelta > 200;
// Check if the old and new location are from the same provider
boolean isFromSameProvider = isSameProvider(location.getProvider(),
currentBestLocation.getProvider());
// Determine location quality using a combination of timeliness and accuracy
if (isMoreAccurate) {
return true;
} else if (isNewer && !isLessAccurate) {
return true;
} else if (isNewer && !isSignificantlyLessAccurate && isFromSameProvider) {
return true;
}
return false;
}
// Checks whether two providers are the same
private boolean isSameProvider(String provider1, String provider2) {
if (provider1 == null) {
return provider2 == null;
}
return provider1.equals(provider2);
}
....
您可以通过 找到位置GPS_PROVIDER or NETWORK_PROVIDER
。
Android中的位置服务概述。
这是一个尝试使用 GPS 查找位置的示例。如果您的 GPS 不可用,请尝试使用网络查找位置。
GPSTracker.java
public class GPSTracker extends Service implements LocationListener {
private final Context mContext;
// Flag for GPS status
boolean isGPSEnabled = false;
// Flag for network status
boolean isNetworkEnabled = false;
// Flag for GPS status
boolean canGetLocation = false;
Location location; // Location
double latitude; // Latitude
double longitude; // Longitude
// The minimum distance to change Updates in meters
private static final long MIN_DISTANCE_CHANGE_FOR_UPDATES = 10; // 10 meters
// The minimum time between updates in milliseconds
private static final long MIN_TIME_BW_UPDATES = 1000 * 60 * 1; // 1 minute
// Declaring a Location Manager
protected LocationManager locationManager;
public GPSTracker(Context context) {
this.mContext = context;
getLocation();
}
public Location getLocation() {
try {
locationManager = (LocationManager) mContext
.getSystemService(LOCATION_SERVICE);
// Getting GPS status
isGPSEnabled = locationManager
.isProviderEnabled(LocationManager.GPS_PROVIDER);
// Getting network status
isNetworkEnabled = locationManager
.isProviderEnabled(LocationManager.NETWORK_PROVIDER);
if (!isGPSEnabled && !isNetworkEnabled) {
// No network provider is enabled
} else {
this.canGetLocation = true;
if (isNetworkEnabled) {
locationManager.requestLocationUpdates(
LocationManager.NETWORK_PROVIDER,
MIN_TIME_BW_UPDATES,
MIN_DISTANCE_CHANGE_FOR_UPDATES, this);
Log.d("Network", "Network");
if (locationManager != null) {
location = locationManager
.getLastKnownLocation(LocationManager.NETWORK_PROVIDER);
if (location != null) {
latitude = location.getLatitude();
longitude = location.getLongitude();
}
}
}
// If GPS enabled, get latitude/longitude using GPS Services
if (isGPSEnabled) {
if (location == null) {
locationManager.requestLocationUpdates(
LocationManager.GPS_PROVIDER,
MIN_TIME_BW_UPDATES,
MIN_DISTANCE_CHANGE_FOR_UPDATES, this);
Log.d("GPS Enabled", "GPS Enabled");
if (locationManager != null) {
location = locationManager
.getLastKnownLocation(LocationManager.GPS_PROVIDER);
if (location != null) {
latitude = location.getLatitude();
longitude = location.getLongitude();
}
}
}
}
}
}
catch (Exception e) {
e.printStackTrace();
}
return location;
}
/**
* Stop using GPS listener
* Calling this function will stop using GPS in your app.
* */
public void stopUsingGPS(){
if(locationManager != null){
locationManager.removeUpdates(GPSTracker.this);
}
}
/**
* Function to get latitude
* */
public double getLatitude(){
if(location != null){
latitude = location.getLatitude();
}
// return latitude
return latitude;
}
/**
* Function to get longitude
* */
public double getLongitude(){
if(location != null){
longitude = location.getLongitude();
}
// return longitude
return longitude;
}
/**
* Function to check GPS/Wi-Fi enabled
* @return boolean
* */
public boolean canGetLocation() {
return this.canGetLocation;
}
/**
* Function to show settings alert dialog.
* On pressing the Settings button it will launch Settings Options.
* */
public void showSettingsAlert(){
AlertDialog.Builder alertDialog = new AlertDialog.Builder(mContext);
// Setting Dialog Title
alertDialog.setTitle("GPS is settings");
// Setting Dialog Message
alertDialog.setMessage("GPS is not enabled. Do you want to go to settings menu?");
// On pressing the Settings button.
alertDialog.setPositiveButton("Settings", new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog,int which) {
Intent intent = new Intent(Settings.ACTION_LOCATION_SOURCE_SETTINGS);
mContext.startActivity(intent);
}
});
// On pressing the cancel button
alertDialog.setNegativeButton("Cancel", new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int which) {
dialog.cancel();
}
});
// Showing Alert Message
alertDialog.show();
}
@Override
public void onLocationChanged(Location location) {
}
@Override
public void onProviderDisabled(String provider) {
}
@Override
public void onProviderEnabled(String provider) {
}
@Override
public void onStatusChanged(String provider, int status, Bundle extras) {
}
@Override
public IBinder onBind(Intent arg0) {
return null;
}
}
活动 -AndroidGPSTrackingActivity.java
public class AndroidGPSTrackingActivity extends Activity {
Button btnShowLocation;
// GPSTracker class
GPSTracker gps;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
btnShowLocation = (Button) findViewById(R.id.btnShowLocation);
// Show location button click event
btnShowLocation.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View arg0) {
// Create class object
gps = new GPSTracker(AndroidGPSTrackingActivity.this);
// Check if GPS enabled
if(gps.canGetLocation()) {
double latitude = gps.getLatitude();
double longitude = gps.getLongitude();
// \n is for new line
Toast.makeText(getApplicationContext(), "Your Location is - \nLat: " + latitude + "\nLong: " + longitude, Toast.LENGTH_LONG).show();
} else {
// Can't get location.
// GPS or network is not enabled.
// Ask user to enable GPS/network in settings.
gps.showSettingsAlert();
}
}
});
}
}
布局 - main.xml
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >
<Button android:id="@+id/btnShowLocation"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Show Location"
android:layout_centerVertical="true"
android:layout_centerHorizontal="true"/>
</RelativeLayout>
AndroidManifest.xml
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
<uses-permission android:name="android.permission.INTERNET" />
那里已经有很多答案,但我想展示使用 Google API 获取位置的最新方法,因此新程序员可以使用新方法:
我已经在我的博客demouts.com上写了关于android 当前位置的详细教程。您还可以找到使用 android studio 开发的完整源代码。
首先,把它放在 gradle 文件中
compile 'com.google.android.gms:play-services:9.0.2'
然后实现必要的接口
public class MainActivity extends BaseActivitiy implements GoogleApiClient.ConnectionCallbacks, GoogleApiClient.OnConnectionFailedListener, com.google.android.gms.location.LocationListener
声明实例
private GoogleApiClient mGoogleApiClient;
private Location mLocation;
private LocationManager locationManager;
private LocationRequest mLocationRequest;
把这个放进去onCreate()
mGoogleApiClient = new GoogleApiClient.Builder(this)
.addConnectionCallbacks(this)
.addOnConnectionFailedListener(this)
.addApi(LocationServices.API)
.build();
locationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
最后,覆盖必要的方法
@Override
public void onConnected(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) {
// 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;
} startLocationUpdates();
mLocation = LocationServices.FusedLocationApi.getLastLocation(mGoogleApiClient);
if(mLocation == null){
startLocationUpdates();
}
if (mLocation != null) {
double latitude = mLocation.getLatitude();
double longitude = mLocation.getLongitude();
} else {
// Toast.makeText(this, "Location not Detected", Toast.LENGTH_SHORT).show();
}
}
protected void startLocationUpdates() {
// Create the location request
mLocationRequest = LocationRequest.create()
.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY)
.setInterval(UPDATE_INTERVAL)
.setFastestInterval(FASTEST_INTERVAL);
// Request location updates
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;
}
LocationServices.FusedLocationApi.requestLocationUpdates(mGoogleApiClient,
mLocationRequest, this);
Log.d("reque", "--->>>>");
}
@Override
public void onConnectionSuspended(int i) {
Log.i(TAG, "Connection Suspended");
mGoogleApiClient.connect();
}
@Override
public void onConnectionFailed(ConnectionResult connectionResult) {
Log.i(TAG, "Connection failed. Error: " + connectionResult.getErrorCode());
}
@Override
public void onStart() {
super.onStart();
mGoogleApiClient.connect();
}
@Override
public void onStop() {
super.onStop();
if (mGoogleApiClient.isConnected()) {
mGoogleApiClient.disconnect();
}
}
@Override
public void onLocationChanged(Location location) {
}
在运行应用程序之前,不要忘记在您的设备中启动 GPS。
由于我不喜欢其他答案中的某些代码,因此这是我的简单解决方案。此解决方案旨在用于 Activity 或 Service 以跟踪位置。它确保它永远不会返回太陈旧的数据,除非您明确请求陈旧数据。它可以以回调模式运行以在我们收到更新时获取更新,也可以以轮询模式运行以轮询最新信息。
通用 LocationTracker 接口。允许我们拥有多种类型的位置跟踪器并轻松插入适当的位置跟踪器:
package com.gabesechan.android.reusable.location;
import android.location.Location;
public interface LocationTracker {
public interface LocationUpdateListener{
public void onUpdate(Location oldLoc, long oldTime, Location newLoc, long newTime);
}
public void start();
public void start(LocationUpdateListener update);
public void stop();
public boolean hasLocation();
public boolean hasPossiblyStaleLocation();
public Location getLocation();
public Location getPossiblyStaleLocation();
}
ProviderLocationTracker - 此类将跟踪 GPS 或 NETWORK 的位置。
package com.gabesechan.android.reusable.location;
import android.content.Context;
import android.location.Location;
import android.location.LocationListener;
import android.location.LocationManager;
import android.os.Bundle;
public class ProviderLocationTracker implements LocationListener, LocationTracker {
// The minimum distance to change Updates in meters
private static final long MIN_UPDATE_DISTANCE = 10;
// The minimum time between updates in milliseconds
private static final long MIN_UPDATE_TIME = 1000 * 60;
private LocationManager lm;
public enum ProviderType{
NETWORK,
GPS
};
private String provider;
private Location lastLocation;
private long lastTime;
private boolean isRunning;
private LocationUpdateListener listener;
public ProviderLocationTracker(Context context, ProviderType type) {
lm = (LocationManager)context.getSystemService(Context.LOCATION_SERVICE);
if(type == ProviderType.NETWORK){
provider = LocationManager.NETWORK_PROVIDER;
}
else{
provider = LocationManager.GPS_PROVIDER;
}
}
public void start(){
if(isRunning){
//Already running, do nothing
return;
}
//The provider is on, so start getting updates. Update current location
isRunning = true;
lm.requestLocationUpdates(provider, MIN_UPDATE_TIME, MIN_UPDATE_DISTANCE, this);
lastLocation = null;
lastTime = 0;
return;
}
public void start(LocationUpdateListener update) {
start();
listener = update;
}
public void stop(){
if(isRunning){
lm.removeUpdates(this);
isRunning = false;
listener = null;
}
}
public boolean hasLocation(){
if(lastLocation == null){
return false;
}
if(System.currentTimeMillis() - lastTime > 5 * MIN_UPDATE_TIME){
return false; //stale
}
return true;
}
public boolean hasPossiblyStaleLocation(){
if(lastLocation != null){
return true;
}
return lm.getLastKnownLocation(provider)!= null;
}
public Location getLocation(){
if(lastLocation == null){
return null;
}
if(System.currentTimeMillis() - lastTime > 5 * MIN_UPDATE_TIME){
return null; //stale
}
return lastLocation;
}
public Location getPossiblyStaleLocation(){
if(lastLocation != null){
return lastLocation;
}
return lm.getLastKnownLocation(provider);
}
public void onLocationChanged(Location newLoc) {
long now = System.currentTimeMillis();
if(listener != null){
listener.onUpdate(lastLocation, lastTime, newLoc, now);
}
lastLocation = newLoc;
lastTime = now;
}
public void onProviderDisabled(String arg0) {
}
public void onProviderEnabled(String arg0) {
}
public void onStatusChanged(String arg0, int arg1, Bundle arg2) {
}
}
这是 FallbackLocationTracker,它将通过 GPS 和 NETWORK 进行跟踪,并使用更准确的位置。
package com.gabesechan.android.reusable.location;
import android.content.Context;
import android.location.Location;
import android.location.LocationManager;
public class FallbackLocationTracker implements LocationTracker, LocationTracker.LocationUpdateListener {
private boolean isRunning;
private ProviderLocationTracker gps;
private ProviderLocationTracker net;
private LocationUpdateListener listener;
Location lastLoc;
long lastTime;
public FallbackLocationTracker(Context context) {
gps = new ProviderLocationTracker(context, ProviderLocationTracker.ProviderType.GPS);
net = new ProviderLocationTracker(context, ProviderLocationTracker.ProviderType.NETWORK);
}
public void start(){
if(isRunning){
//Already running, do nothing
return;
}
//Start both
gps.start(this);
net.start(this);
isRunning = true;
}
public void start(LocationUpdateListener update) {
start();
listener = update;
}
public void stop(){
if(isRunning){
gps.stop();
net.stop();
isRunning = false;
listener = null;
}
}
public boolean hasLocation(){
//If either has a location, use it
return gps.hasLocation() || net.hasLocation();
}
public boolean hasPossiblyStaleLocation(){
//If either has a location, use it
return gps.hasPossiblyStaleLocation() || net.hasPossiblyStaleLocation();
}
public Location getLocation(){
Location ret = gps.getLocation();
if(ret == null){
ret = net.getLocation();
}
return ret;
}
public Location getPossiblyStaleLocation(){
Location ret = gps.getPossiblyStaleLocation();
if(ret == null){
ret = net.getPossiblyStaleLocation();
}
return ret;
}
public void onUpdate(Location oldLoc, long oldTime, Location newLoc, long newTime) {
boolean update = false;
//We should update only if there is no last location, the provider is the same, or the provider is more accurate, or the old location is stale
if(lastLoc == null){
update = true;
}
else if(lastLoc != null && lastLoc.getProvider().equals(newLoc.getProvider())){
update = true;
}
else if(newLoc.getProvider().equals(LocationManager.GPS_PROVIDER)){
update = true;
}
else if (newTime - lastTime > 5 * 60 * 1000){
update = true;
}
if(update){
if(listener != null){
listener.onUpdate(lastLoc, lastTime, newLoc, newTime);
}
lastLoc = newLoc;
lastTime = newTime;
}
}
}
由于两者都实现了 LocationTracker 接口,您可以轻松地改变使用哪个接口的想法。要在轮询模式下运行类,只需调用 start()。要在更新模式下运行它,请调用 start(Listener)。
还可以看看我关于代码的博客文章
通过 - 获取 gps 的位置
LocationManager locationManager = (LocationManager) context.getSystemService(Context.LOCATION_SERVICE);
LocationListener locationListener = new LocationListener()
{
@Override
public void onStatusChanged(String provider, int status, Bundle extras) {
// TODO Auto-generated method stub
}
@Override
public void onProviderEnabled(String provider) {
// TODO Auto-generated method stub
}
@Override
public void onProviderDisabled(String provider) {
// TODO Auto-generated method stub
}
@Override
public void onLocationChanged(Location location) {
// TODO Auto-generated method stub
double latitude = location.getLatitude();
double longitude = location.getLongitude();
double speed = location.getSpeed(); //spedd in meter/minute
speed = (speed*3600)/1000; // speed in km/minute Toast.makeText(GraphViews.this, "Current speed:" + location.getSpeed(),Toast.LENGTH_SHORT).show();
}
};
locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, 0, 0, locationListener);
}
您需要使用最新/最新的
GoogleApiClient Api
基本上你需要做的是:
private GoogleApiClient mGoogleApiClient;
mGoogleApiClient = new GoogleApiClient.Builder(this)
.addApi(LocationServices.API)
.addConnectionCallbacks(this)
.addOnConnectionFailedListener(this)
.build();
然后
@Override
public void onConnected(Bundle connectionHint) {
mLastLocation = LocationServices.FusedLocationApi.getLastLocation(
mGoogleApiClient);
if (mLastLocation != null) {
mLatitudeText.setText(String.valueOf(mLastLocation.getLatitude()));
mLongitudeText.setText(String.valueOf(mLastLocation.getLongitude()));
}
}
以获得最准确和可靠的位置。在这里查看我的帖子:
https://stackoverflow.com/a/33599228/2644905
不要使用不准确且响应延迟的 LocationListener。老实说,这更容易实现。另请阅读文档:https ://developers.google.com/android/reference/com/google/android/gms/common/api/GoogleApiClient
As of the second half of 2020, there is a much easier way to do this.
Excluding requesting permissions (which I will include at the bottom for devs newer to this), below is the code.
Just remember, you need to include at least this version of the library in your dependencies (in the app's build.gradle
):
implementation 'com.google.android.gms:play-services-location:17.1.0'
... and of course the fine permission in your manifest:
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
Kotlin (first the setup):
private val fusedLocationClient: FusedLocationProviderClient by lazy {
LocationServices.getFusedLocationProviderClient(applicationContext)
}
private var cancellationTokenSource = CancellationTokenSource()
Then the main code (for FINE_LOCATION):
private fun requestCurrentLocation() {
// Check Fine permission
if (ActivityCompat.checkSelfPermission(
this,
Manifest.permission.ACCESS_FINE_LOCATION) ==
PackageManager.PERMISSION_GRANTED) {
// Main code
val currentLocationTask: Task<Location> = fusedLocationClient.getCurrentLocation(
PRIORITY_HIGH_ACCURACY,
cancellationTokenSource.token
)
currentLocationTask.addOnCompleteListener { task: Task<Location> ->
val result = if (task.isSuccessful) {
val result: Location = task.result
"Location (success): ${result.latitude}, ${result.longitude}"
} else {
val exception = task.exception
"Location (failure): $exception"
}
Log.d(TAG, "getCurrentLocation() result: $result")
}
} else {
// Request fine location permission (full code below).
}
If you prefer Java, it looks like this:
public class JavaVersion extends AppCompatActivity {
private final String TAG = "MainActivity";
// The Fused Location Provider provides access to location APIs.
private FusedLocationProviderClient fusedLocationClient;
// Allows class to cancel the location request if it exits the activity.
// Typically, you use one cancellation source per lifecycle.
private final CancellationTokenSource cancellationTokenSource = new CancellationTokenSource();
@Override
protected void onCreate(@Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
fusedLocationClient = LocationServices.getFusedLocationProviderClient(this);
}
...
private void requestCurrentLocation() {
Log.d(TAG, "requestCurrentLocation()");
// Request permission
if (ActivityCompat.checkSelfPermission(
this,
Manifest.permission.ACCESS_FINE_LOCATION) ==
PackageManager.PERMISSION_GRANTED) {
// Main code
Task<Location> currentLocationTask = fusedLocationClient.getCurrentLocation(
PRIORITY_HIGH_ACCURACY,
cancellationTokenSource.getToken()
);
currentLocationTask.addOnCompleteListener((new OnCompleteListener<Location>() {
@Override
public void onComplete(@NonNull Task<Location> task) {
String result = "";
if (task.isSuccessful()) {
// Task completed successfully
Location location = task.getResult();
result = "Location (success): " +
location.getLatitude() +
", " +
location.getLongitude();
} else {
// Task failed with an exception
Exception exception = task.getException();
result = "Exception thrown: " + exception;
}
Log.d(TAG, "getCurrentLocation() result: " + result);
}
}));
} else {
// TODO: Request fine location permission
Log.d(TAG, "Request fine location permission.");
}
}
...
}
The arguments:
- PRIORITY type is self-explanatory. (Other options are PRIORITY_BALANCED_POWER_ACCURACY, PRIORITY_LOW_POWER, and PRIORITY_NO_POWER.)
- CancellationToken - This allows you to cancel the request if, for instance, the user navigates away from your Activity.
Example (Kotlin):
override fun onStop() {
super.onStop()
// Cancels location request (if in flight).
cancellationTokenSource.cancel()
}
That's it.
Now, this does use the FusedLocationProviderClient which is a Google Play Services APIs.
That means this works on all Android devices with the Google Play Store (which is a lot of them). However, for devices in China without the Play Store, this won't work, so take that into account.
For developers who are a little newer to this, you need to request the fine (or coarse) location permission if the user hasn't approved it yet, so in the code above, I would request the location permission.
Below is the full code (in Kotlin).
I hope that helps (and makes your live's a little easier)!
/**
* Demonstrates how to easily get the current location via the [FusedLocationProviderClient.getCurrentLocation].
* The main code is in this class's requestCurrentLocation() method.
*/
class MainActivity : AppCompatActivity() {
private lateinit var binding: ActivityMainBinding
// The Fused Location Provider provides access to location APIs.
private val fusedLocationClient: FusedLocationProviderClient by lazy {
LocationServices.getFusedLocationProviderClient(applicationContext)
}
// Allows class to cancel the location request if it exits the activity.
// Typically, you use one cancellation source per lifecycle.
private var cancellationTokenSource = CancellationTokenSource()
// If the user denied a previous permission request, but didn't check "Don't ask again", this
// Snackbar provides an explanation for why user should approve, i.e., the additional rationale.
private val fineLocationRationalSnackbar by lazy {
Snackbar.make(
binding.container,
R.string.fine_location_permission_rationale,
Snackbar.LENGTH_LONG
).setAction(R.string.ok) {
requestPermissions(
arrayOf(Manifest.permission.ACCESS_FINE_LOCATION),
REQUEST_FINE_LOCATION_PERMISSIONS_REQUEST_CODE
)
}
}
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
binding = ActivityMainBinding.inflate(layoutInflater)
val view = binding.root
setContentView(view)
}
override fun onStop() {
super.onStop()
// Cancels location request (if in flight).
cancellationTokenSource.cancel()
}
override fun onRequestPermissionsResult(
requestCode: Int,
permissions: Array<String>,
grantResults: IntArray
) {
Log.d(TAG, "onRequestPermissionResult()")
if (requestCode == REQUEST_FINE_LOCATION_PERMISSIONS_REQUEST_CODE) {
when {
grantResults.isEmpty() ->
// If user interaction was interrupted, the permission request
// is cancelled and you receive an empty array.
Log.d(TAG, "User interaction was cancelled.")
grantResults[0] == PackageManager.PERMISSION_GRANTED ->
Snackbar.make(
binding.container,
R.string.permission_approved_explanation,
Snackbar.LENGTH_LONG
)
.show()
else -> {
Snackbar.make(
binding.container,
R.string.fine_permission_denied_explanation,
Snackbar.LENGTH_LONG
)
.setAction(R.string.settings) {
// Build intent that displays the App settings screen.
val intent = Intent()
intent.action = Settings.ACTION_APPLICATION_DETAILS_SETTINGS
val uri = Uri.fromParts(
"package",
BuildConfig.APPLICATION_ID,
null
)
intent.data = uri
intent.flags = Intent.FLAG_ACTIVITY_NEW_TASK
startActivity(intent)
}
.show()
}
}
}
}
fun locationRequestOnClick(view: View) {
Log.d(TAG, "locationRequestOnClick()")
requestCurrentLocation()
}
/**
* Gets current location.
* Note: The code checks for permission before calling this method, that is, it's never called
* from a method with a missing permission. Also, I include a second check with my extension
* function in case devs just copy/paste this code.
*/
private fun requestCurrentLocation() {
Log.d(TAG, "requestCurrentLocation()")
if (ActivityCompat.checkSelfPermission(
this,
Manifest.permission.ACCESS_FINE_LOCATION) ==
PackageManager.PERMISSION_GRANTED) {
// Returns a single current location fix on the device. Unlike getLastLocation() that
// returns a cached location, this method could cause active location computation on the
// device. A single fresh location will be returned if the device location can be
// determined within reasonable time (tens of seconds), otherwise null will be returned.
//
// Both arguments are required.
// PRIORITY type is self-explanatory. (Other options are PRIORITY_BALANCED_POWER_ACCURACY,
// PRIORITY_LOW_POWER, and PRIORITY_NO_POWER.)
// The second parameter, [CancellationToken] allows the activity to cancel the request
// before completion.
val currentLocationTask: Task<Location> = fusedLocationClient.getCurrentLocation(
PRIORITY_HIGH_ACCURACY,
cancellationTokenSource.token
)
currentLocationTask.addOnCompleteListener { task: Task<Location> ->
val result = if (task.isSuccessful) {
val result: Location = task.result
"Location (success): ${result.latitude}, ${result.longitude}"
} else {
val exception = task.exception
"Location (failure): $exception"
}
Log.d(TAG, "getCurrentLocation() result: $result")
logOutputToScreen(result)
}
} else {
val provideRationale = shouldShowRequestPermissionRationale(Manifest.permission.ACCESS_FINE_LOCATION)
if (provideRationale) {
fineLocationRationalSnackbar.show()
} else {
requestPermissions(arrayOf(Manifest.permission.ACCESS_FINE_LOCATION), REQUEST_FINE_LOCATION_PERMISSIONS_REQUEST_CODE)
}
}
}
private fun logOutputToScreen(outputString: String) {
val finalOutput = binding.outputTextView.text.toString() + "\n" + outputString
binding.outputTextView.text = finalOutput
}
companion object {
private const val TAG = "MainActivity"
private const val REQUEST_FINE_LOCATION_PERMISSIONS_REQUEST_CODE = 34
}
}
class MyLocation {
Timer timer1;
LocationManager lm;
LocationResult locationResult;
boolean gps_enabled = false;
boolean network_enabled = false;
public boolean getLocation(Context context, LocationResult result) {
// I use LocationResult callback class to pass location value from
// MyLocation to user code.
locationResult = result;
if (lm == null)
lm = (LocationManager) context
.getSystemService(Context.LOCATION_SERVICE);
// Exceptions will be thrown if the provider is not permitted.
try {
gps_enabled = lm.isProviderEnabled(LocationManager.GPS_PROVIDER);
}
catch (Exception ex) {
}
try {
network_enabled = lm
.isProviderEnabled(LocationManager.NETWORK_PROVIDER);
}
catch (Exception ex) {
}
// Don't start listeners if no provider is enabled.
if (!gps_enabled && !network_enabled)
return false;
if (gps_enabled)
lm.requestLocationUpdates(LocationManager.GPS_PROVIDER, 0, 0,
locationListenerGps);
if (network_enabled)
lm.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, 0, 0,
locationListenerNetwork);
timer1 = new Timer();
timer1.schedule(new GetLastLocation(), 5000);
return true;
}
LocationListener locationListenerGps = new LocationListener() {
public void onLocationChanged(Location location) {
timer1.cancel();
locationResult.gotLocation(location);
lm.removeUpdates(this);
lm.removeUpdates(locationListenerNetwork);
}
public void onProviderDisabled(String provider) {
}
public void onProviderEnabled(String provider) {
}
public void onStatusChanged(String provider, int status, Bundle extras) {
}
};
LocationListener locationListenerNetwork = new LocationListener() {
public void onLocationChanged(Location location) {
timer1.cancel();
locationResult.gotLocation(location);
lm.removeUpdates(this);
lm.removeUpdates(locationListenerGps);
}
public void onProviderDisabled(String provider) {
}
public void onProviderEnabled(String provider) {
}
public void onStatusChanged(String provider, int status, Bundle extras) {
}
};
class GetLastLocation extends TimerTask {
@Override
public void run() {
lm.removeUpdates(locationListenerGps);
lm.removeUpdates(locationListenerNetwork);
Location net_loc = null, gps_loc = null;
if (gps_enabled)
gps_loc = lm.getLastKnownLocation(LocationManager.GPS_PROVIDER);
if (network_enabled)
net_loc = lm
.getLastKnownLocation(LocationManager.NETWORK_PROVIDER);
// If there are both values, use the latest one.
if (gps_loc != null && net_loc != null) {
if (gps_loc.getTime() > net_loc.getTime())
locationResult.gotLocation(gps_loc);
else
locationResult.gotLocation(net_loc);
return;
}
if (gps_loc != null) {
locationResult.gotLocation(gps_loc);
return;
}
if (net_loc != null) {
locationResult.gotLocation(net_loc);
return;
}
locationResult.gotLocation(null);
}
}
public static abstract class LocationResult {
public abstract void gotLocation(Location location);
}
}
我希望这能帮到您...
现在Google Play 位置服务已经出现,我建议开发人员开始使用新的融合位置提供程序。您会发现它更易于使用且更准确。请观看Google I/O视频Beyond the Blue Dot:Android Location 中的新功能,由创建新 Google Play 位置服务 API 的两个人制作。
我一直在许多移动平台上使用位置 API,我认为这两个家伙所做的确实是革命性的。它消除了使用各种提供程序的大量复杂性。Stack Overflow 充斥着关于使用哪个提供商、是否使用最后一个已知位置、如何在 LocationManager 上设置其他属性等问题。他们构建的这个新 API 消除了大部分不确定性,并使位置服务成为一种乐趣利用。
我编写了一个 Android 应用程序,该应用程序使用 Google Play 定位服务定期获取位置,并将位置发送到 Web 服务器,该服务器存储在数据库中,可以在Google Maps上查看。我编写了客户端软件(适用于 Android、iOS、Windows Phone 和Java ME)和服务器软件(适用于 ASP.NET 和SQL Server或PHP和MySQL)。该软件在每个平台上都是用本地语言编写的,并且可以在每个平台的后台正常运行。最后,该软件具有MIT 许可证。您可以在此处找到 Android 客户端:
https://github.com/nickfox/GpsTracker/tree/master/phoneClients/android
GoogleSamples有使用最新的 FusedLocationProviderApi 的详细示例。不幸的是,最受好评的答案已经过时了。
按照以下示例使用 FusedLocationProviderApi 实现定位服务
https://github.com/googlesamples/android-play-location/tree/master/LocationUpdates
在 Android 中获取位置更新需要大量的样板代码,您需要注意
- Google Play 服务可用性检查,
- 更新旧的或不可用的 Google Play 服务
- GoogleApiClient 的对话框创建及其回调连接、断开连接等。
- 停止和释放用于位置更新的资源
- 处理位置权限场景
- 检查位置服务是打开还是关闭
- 获取最后一个位置也不是那么容易
- 如果在一定时间后没有获得位置,则回退到最后一个已知位置
为了简化所有这些步骤,我创建了Android-EasyLocation(小型 android 库),它将处理所有这些内容,您可以专注于业务逻辑。
您所需要的只是扩展EasyLocationActivity和这个
requestSingleLocationFix(easyLocationRequest);
或者
requestLocationUpdates(easyLocationRequest);
在https://github.com/akhgupta/Android-EasyLocation处查看所需的示例应用程序和步骤
LocationManager 是一个提供内置方法来获取最后知道位置的类
第 1 步:创建一个 LocationManager 对象,如下所示
LocationManager locationManager = (LocationManager) context.getSystemService(Context.LOCATION_SERVICE);
第 2 步:添加标准
*Criteria is use for setting accuracy*
Criteria criteria = new Criteria();
int currentapiVersion = android.os.Build.VERSION.SDK_INT;
if (currentapiVersion >= android.os.Build.VERSION_CODES.HONEYCOMB) {
criteria.setSpeedAccuracy(Criteria.ACCURACY_HIGH);
criteria.setAccuracy(Criteria.ACCURACY_FINE);
criteria.setAltitudeRequired(true);
criteria.setBearingRequired(true);
criteria.setSpeedRequired(true);
}
第 3 步:获取可用的提供者
有两种类型的提供商 GPS 和网络
String provider = locationManager.getBestProvider(criteria, true);
第 4 步:获取最后知道的位置
Location location = locationManager.getLastKnownLocation(provider);
第 5 步:获取纬度和经度
如果位置对象为空,则不要尝试调用下面的方法
getLatitude and getLongitude is methods which returns double values
我做了一个项目,我们可以使用 Google Play 服务、GPS 和网络提供商从中获得准确的位置。这个项目可以在这里找到。
寻找最佳位置的策略是,如果找到位置,首先从谷歌播放服务获取位置,然后检查天气是否更好,如果找到的位置为空,则重新启动谷歌播放服务并尝试从 Android 位置 API 获取位置。在更改侦听器上注册位置,当找到更好的位置时,回调将其返回到主要活动。
在代码中使用和实现非常简单,只需要嵌入两个类,即实现接口LocationManagerInterface
并使用 SmartLocationManager 获取位置。SmartLocationManager
LocationActivity
/**
* Created by Syed Raza Mehdi Naqvi on 8/10/2016.
*/
public interface LocationManagerInterface {
String TAG = LocationManagerInterface.class.getSimpleName();
void locationFetched(Location mLocation, Location oldLocation, String time, String locationProvider);
}
这是位置管理器类
import android.Manifest;
import android.app.Activity;
import android.content.Context;
import android.content.DialogInterface;
import android.content.Intent;
import android.content.IntentSender;
import android.content.pm.PackageManager;
import android.location.Location;
import android.location.LocationManager;
import android.os.Build;
import android.os.Bundle;
import android.support.v4.app.ActivityCompat;
import android.support.v4.content.ContextCompat;
import android.support.v7.app.AlertDialog;
import android.util.Log;
import android.widget.Toast;
import com.google.android.gms.common.ConnectionResult;
import com.google.android.gms.common.GooglePlayServicesUtil;
import com.google.android.gms.common.api.GoogleApiClient;
import com.google.android.gms.location.LocationListener;
import com.google.android.gms.location.LocationRequest;
import com.google.android.gms.location.LocationServices;
import java.text.DateFormat;
import java.util.Date;
/**
* Created by Syed Raza Mehdi Naqvi on 8/9/2016.
*/
public class SmartLocationManager implements
GoogleApiClient.ConnectionCallbacks, GoogleApiClient.OnConnectionFailedListener, LocationListener {
private static final String TAG = SmartLocationManager.class.getSimpleName();
private static final int TWO_MINUTES = 1000 * 60 * 2;
private static final int PERMISSION_REQUEST_CODE = 1000;
private static final int CONNECTION_FAILURE_RESOLUTION_REQUEST = 9000;
// default value is false but user can change it
private String mLastLocationUpdateTime; // fetched location time
private String locationProvider; // source of fetched location
private Location mLastLocationFetched; // location fetched
private Location mLocationFetched; // location fetched
private Location networkLocation;
private Location gpsLocation;
private int mLocationPiority;
private long mLocationFetchInterval;
private long mFastestLocationFetchInterval;
private Context mContext; // application context
private Activity mActivity; // activity context
private LocationRequest mLocationRequest;
private GoogleApiClient mGoogleApiClient;
private LocationManagerInterface mLocationManagerInterface;
private android.location.LocationManager locationManager;
private android.location.LocationListener locationListener;
boolean isGPSEnabled;
boolean isNetworkEnabled;
private int mProviderType;
public static final int NETWORK_PROVIDER = 1;
public static final int ALL_PROVIDERS = 0;
public static final int GPS_PROVIDER = 2;
// private final double STANDARD_LOCATION_ACCURACY = 100.0;
// private final double STANDARD_LOCATION_SEED_LIMIT = 6.95;
public static final int LOCATION_PROVIDER_ALL_RESTICTION = 1;
public static final int LOCATION_PROVIDER_RESTRICTION_NONE = 0;
public static final int LOCATION_PROVIDER_GPS_ONLY_RESTICTION = 2;
public static final int LOCATION_PROVIDER_NETWORK_ONLY_RESTICTION = 3;
private int mForceNetworkProviders = 0;
public SmartLocationManager(Context context, Activity activity, LocationManagerInterface locationInterface, int providerType, int locationPiority, long locationFetchInterval, long fastestLocationFetchInterval, int forceNetworkProviders) {
mContext = context;
mActivity = activity;
mProviderType = providerType;
mLocationPiority = locationPiority;
mForceNetworkProviders = forceNetworkProviders;
mLocationFetchInterval = locationFetchInterval;
mFastestLocationFetchInterval = fastestLocationFetchInterval;
mLocationManagerInterface = locationInterface;
initSmartLocationManager();
}
public void initSmartLocationManager() {
// 1) ask for permission for Android 6 above to avoid crash
// 2) check if gps is available
// 3) get location using awesome strategy
askLocationPermission(); // for android version 6 above
checkNetworkProviderEnable(mForceNetworkProviders); //
if (isGooglePlayServicesAvailable()) // if googleplay services available
initLocationObjts(); // init obj for google play service and start fetching location
else
getLocationUsingAndroidAPI(); // otherwise get location using Android API
}
private void initLocationObjts() {
// Create the LocationRequest object
mLocationRequest = LocationRequest.create()
.setPriority(mLocationPiority)
.setInterval(mLocationFetchInterval) // 10 seconds, in milliseconds
.setFastestInterval(mFastestLocationFetchInterval); // 1 second, in milliseconds
if (mGoogleApiClient == null) {
mGoogleApiClient = new GoogleApiClient.Builder(mActivity)
.addConnectionCallbacks(this)
.addOnConnectionFailedListener(this)
.addApi(LocationServices.API)
.build();
}
startLocationFetching(); // connect google play services to fetch location
}
@Override
public void onConnected(Bundle connectionHint) {
Location location = LocationServices.FusedLocationApi.getLastLocation(mGoogleApiClient);
startLocationUpdates();
if (location == null) {
LocationServices.FusedLocationApi.requestLocationUpdates(mGoogleApiClient, mLocationRequest, this);
getLocationUsingAndroidAPI();
} else {
setNewLocation(getBetterLocation(location, mLocationFetched), mLocationFetched);
}
}
@Override
public void onLocationChanged(Location location) {
if (location == null) {
getLastKnownLocation();
} else {
setNewLocation(getBetterLocation(location, mLocationFetched), mLocationFetched);
}
}
@Override
public void onConnectionSuspended(int i) {
Log.i(TAG, "Connection suspended");
}
@Override
public void onConnectionFailed(ConnectionResult connectionResult) {
if (connectionResult.hasResolution()) {
try {
connectionResult.startResolutionForResult(mActivity, CONNECTION_FAILURE_RESOLUTION_REQUEST); // Start an Activity that tries to resolve the error
getLocationUsingAndroidAPI(); // try to get location using Android API locationManager
} catch (IntentSender.SendIntentException e) {
e.printStackTrace();
}
} else {
Log.i(TAG, "Location services connection failed with code " + connectionResult.getErrorCode());
}
}
private void setNewLocation(Location location, Location oldLocation) {
if (location != null) {
mLastLocationFetched = oldLocation;
mLocationFetched = location;
mLastLocationUpdateTime = DateFormat.getTimeInstance().format(new Date());
locationProvider = location.getProvider();
mLocationManagerInterface.locationFetched(location, mLastLocationFetched, mLastLocationUpdateTime, location.getProvider());
}
}
private void getLocationUsingAndroidAPI() {
// Acquire a reference to the system Location Manager
locationManager = (LocationManager) mContext.getSystemService(Context.LOCATION_SERVICE);
setLocationListner();
captureLocation();
}
public void captureLocation() {
if (Build.VERSION.SDK_INT >= 23 &&
ContextCompat.checkSelfPermission(mContext, android.Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED &&
ContextCompat.checkSelfPermission(mContext, android.Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
return;
}
try {
if (mProviderType == SmartLocationManager.GPS_PROVIDER) {
locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, 0, 0, locationListener);
} else if (mProviderType == SmartLocationManager.NETWORK_PROVIDER) {
locationManager.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, 0, 0, locationListener);
} else {
locationManager.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, 0, 0, locationListener);
locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, 0, 0, locationListener);
}
} catch (Exception e) {
Log.e(TAG, e.getMessage());
}
}
private void setLocationListner() {
// Define a listener that responds to location updates
locationListener = new android.location.LocationListener() {
public void onLocationChanged(Location location) {
// Called when a new location is found by the network location provider.
if (location == null) {
getLastKnownLocation();
} else {
setNewLocation(getBetterLocation(location, mLocationFetched), mLocationFetched);
// if (isLocationAccurate(location) && location.getAccuracy() < STANDARD_LOCATION_ACCURACY && location.getSpeed() < STANDARD_LOCATION_SEED_LIMIT) {// no use of this if
// setNewLocation(getBetterLocation(location, mLocationFetched), mLocationFetched);
// } else {
// setNewLocation(getBetterLocation(location, mLocationFetched), mLocationFetched);
// }
}
}
public void onStatusChanged(String provider, int status, Bundle extras) {
}
public void onProviderEnabled(String provider) {
}
public void onProviderDisabled(String provider) {
}
};
}
public Location getAccurateLocation() {
if (Build.VERSION.SDK_INT >= 23 &&
ContextCompat.checkSelfPermission(mContext, android.Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED &&
ContextCompat.checkSelfPermission(mContext, android.Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
return null;
}
try {
gpsLocation = locationManager.getLastKnownLocation(LocationManager.GPS_PROVIDER);
networkLocation = locationManager.getLastKnownLocation(LocationManager.NETWORK_PROVIDER);
Location newLocalGPS, newLocalNetwork;
if (gpsLocation != null || networkLocation != null) {
newLocalGPS = getBetterLocation(mLocationFetched, gpsLocation);
newLocalNetwork = getBetterLocation(mLocationFetched, networkLocation);
setNewLocation(getBetterLocation(newLocalGPS, newLocalNetwork), mLocationFetched);
}
} catch (Exception ex) {
Log.e(TAG, ex.getMessage());
}
return mLocationFetched;
}
protected void startLocationUpdates() {
LocationServices.FusedLocationApi.requestLocationUpdates(mGoogleApiClient, mLocationRequest, this);
}
public void startLocationFetching() {
mGoogleApiClient.connect();
if (mGoogleApiClient.isConnected()) {
startLocationUpdates();
}
}
public void pauseLocationFetching() {
if (mGoogleApiClient.isConnected()) {
LocationServices.FusedLocationApi.removeLocationUpdates(mGoogleApiClient, this);
mGoogleApiClient.disconnect();
}
}
public void abortLocationFetching() {
mGoogleApiClient.disconnect();
// Remove the listener you previously added
if (locationManager != null && locationListener != null) {
if (Build.VERSION.SDK_INT >= 23 &&
ContextCompat.checkSelfPermission(mContext, android.Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED &&
ContextCompat.checkSelfPermission(mContext, android.Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
return;
}
try {
locationManager.removeUpdates(locationListener);
locationManager = null;
} catch (Exception ex) {
Log.e(TAG, ex.getMessage());
}
}
}
public void resetLocation() {
mLocationFetched = null;
mLastLocationFetched = null;
networkLocation = null;
gpsLocation = null;
}
// Android M Permission check
public void askLocationPermission() {
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
if (ContextCompat.checkSelfPermission(mActivity, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED
|| ContextCompat.checkSelfPermission(mActivity, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED
) {
if (ActivityCompat.shouldShowRequestPermissionRationale(mActivity, Manifest.permission.ACCESS_COARSE_LOCATION)
|| ActivityCompat.shouldShowRequestPermissionRationale(mActivity, Manifest.permission.ACCESS_FINE_LOCATION)) {
final AlertDialog.Builder builder = new AlertDialog.Builder(mActivity);
builder.setMessage("Please allow all permissions in App Settings for additional functionality.")
.setCancelable(false)
.setPositiveButton("Allow", new DialogInterface.OnClickListener() {
public void onClick(@SuppressWarnings("unused") final DialogInterface dialog, @SuppressWarnings("unused") final int id) {
Toast.makeText(mContext, "Welcome", Toast.LENGTH_SHORT).show();
}
})
.setNegativeButton("Deny", new DialogInterface.OnClickListener() {
public void onClick(final DialogInterface dialog, @SuppressWarnings("unused") final int id) {
mActivity.finish();
}
});
final AlertDialog alert = builder.create();
alert.show();
} else
ActivityCompat.requestPermissions(mActivity, new String[]{Manifest.permission.ACCESS_COARSE_LOCATION
, Manifest.permission.ACCESS_FINE_LOCATION
}, PERMISSION_REQUEST_CODE);
}
}
}
public void checkNetworkProviderEnable(int enforceActive) {
locationManager = (LocationManager) mContext.getSystemService(Context.LOCATION_SERVICE);
isGPSEnabled = locationManager.isProviderEnabled(LocationManager.GPS_PROVIDER);
isNetworkEnabled = locationManager.isProviderEnabled(LocationManager.NETWORK_PROVIDER);
if (!isGPSEnabled && !isNetworkEnabled) {
buildAlertMessageTurnOnLocationProviders("Your location providers seems to be disabled, please enable it", "OK", "Cancel");
} else if (!isGPSEnabled && mForceNetworkProviders == LOCATION_PROVIDER_GPS_ONLY_RESTICTION) {
buildAlertMessageTurnOnLocationProviders("Your GPS seems to be disabled, please enable it", "OK", "Cancel");
} else if (!isNetworkEnabled && mForceNetworkProviders == LOCATION_PROVIDER_NETWORK_ONLY_RESTICTION) {
buildAlertMessageTurnOnLocationProviders("Your Network location provider seems to be disabled, please enable it", "OK", "Cancel");
}
// getting network status
if (!isGPSEnabled && !isNetworkEnabled) {
Toast.makeText(mContext, "Location can't be fetched!", Toast.LENGTH_SHORT).show(); // show alert
mActivity.finish();
}
}
private void buildAlertMessageTurnOnLocationProviders(String message, String positiveButtonText, String negativeButtonText) {
final AlertDialog.Builder builder = new AlertDialog.Builder(mActivity);
builder.setMessage(message)
.setCancelable(false)
.setPositiveButton(positiveButtonText, new DialogInterface.OnClickListener() {
public void onClick(@SuppressWarnings("unused") final DialogInterface dialog, @SuppressWarnings("unused") final int id) {
Intent mIntent = new Intent(android.provider.Settings.ACTION_LOCATION_SOURCE_SETTINGS);
mIntent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
mContext.startActivity(mIntent);
}
})
.setNegativeButton(negativeButtonText, new DialogInterface.OnClickListener() {
public void onClick(final DialogInterface dialog, @SuppressWarnings("unused") final int id) {
mActivity.finish();
}
});
final AlertDialog alert = builder.create();
alert.show();
}
public Location getLastKnownLocation() {
locationProvider = LocationManager.NETWORK_PROVIDER;
Location lastKnownLocation = null;
// Or use LocationManager.GPS_PROVIDER
if (Build.VERSION.SDK_INT >= 23 &&
ContextCompat.checkSelfPermission(mContext, android.Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED &&
ContextCompat.checkSelfPermission(mContext, android.Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
return lastKnownLocation;
}
try {
lastKnownLocation = locationManager.getLastKnownLocation(locationProvider);
return lastKnownLocation;
} catch (Exception e) {
Log.e(TAG, e.getMessage());
}
return lastKnownLocation;
}
public boolean isGooglePlayServicesAvailable() {
int status = GooglePlayServicesUtil.isGooglePlayServicesAvailable(mContext);
if (status == ConnectionResult.SUCCESS) {
return true;
} else {
return false;
}
}
/**
* Determines whether one Location reading is better than the current Location fix
*
* @param location The new Location that you want to evaluate
* @param currentBestLocation The current Location fix, to which you want to compare the new one
*/
protected Location getBetterLocation(Location location, Location currentBestLocation) {
if (currentBestLocation == null) {
// A new location is always better than no location
return location;
}
// Check whether the new location fix is newer or older
long timeDelta = location.getTime() - currentBestLocation.getTime();
boolean isSignificantlyNewer = timeDelta > TWO_MINUTES;
boolean isSignificantlyOlder = timeDelta < -TWO_MINUTES;
boolean isNewer = timeDelta > 0;
// If it's been more than two minutes since the current location, use the new location
// because the user has likely moved
if (isSignificantlyNewer) {
return location;
// If the new location is more than two minutes older, it must be worse
} else if (isSignificantlyOlder) {
return currentBestLocation;
}
// Check whether the new location fix is more or less accurate
int accuracyDelta = (int) (location.getAccuracy() - currentBestLocation.getAccuracy());
boolean isLessAccurate = accuracyDelta > 0;
boolean isMoreAccurate = accuracyDelta < 0;
boolean isSignificantlyLessAccurate = accuracyDelta > 200;
// Check if the old and new location are from the same provider
boolean isFromSameProvider = isSameProvider(location.getProvider(),
currentBestLocation.getProvider());
// Determine location quality using a combination of timeliness and accuracy
if (isMoreAccurate) {
return location;
} else if (isNewer && !isLessAccurate) {
return location;
} else if (isNewer && !isSignificantlyLessAccurate && isFromSameProvider) {
return location;
}
return currentBestLocation;
}
/**
* Checks whether two providers are the same
*/
private boolean isSameProvider(String provider1, String provider2) {
if (provider1 == null) {
return provider2 == null;
}
return provider1.equals(provider2);
}
public boolean isLocationAccurate(Location location) {
if (location.hasAccuracy()) {
return true;
} else {
return false;
}
}
public Location getStaleLocation() {
if (mLastLocationFetched != null) {
return mLastLocationFetched;
}
if (Build.VERSION.SDK_INT >= 23 &&
ContextCompat.checkSelfPermission(mContext, android.Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED &&
ContextCompat.checkSelfPermission(mContext, android.Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
return null;
}
if (mProviderType == SmartLocationManager.GPS_PROVIDER) {
return locationManager.getLastKnownLocation(LocationManager.GPS_PROVIDER);
} else if (mProviderType == SmartLocationManager.NETWORK_PROVIDER) {
return locationManager.getLastKnownLocation(LocationManager.NETWORK_PROVIDER);
} else {
return getBetterLocation(locationManager.getLastKnownLocation(LocationManager.NETWORK_PROVIDER), locationManager.getLastKnownLocation(LocationManager.GPS_PROVIDER));
}
}
}
我们可以将它与活动或片段一起使用,这里我将它与活动一起使用
import android.location.Location;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.widget.TextView;
import android.widget.Toast;
import com.example.raza.locationaware.location.LocationManagerInterface;
import com.example.raza.locationaware.location.SmartLocationManager;
import com.google.android.gms.location.LocationRequest;
public class LocationActivity extends AppCompatActivity implements LocationManagerInterface {
public static final String TAG = LocationActivity.class.getSimpleName();
SmartLocationManager mLocationManager;
TextView mLocalTV, mLocationProviderTV, mlocationTimeTV;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_location);
mLocationManager = new SmartLocationManager(getApplicationContext(), this, this, SmartLocationManager.ALL_PROVIDERS, LocationRequest.PRIORITY_HIGH_ACCURACY, 10 * 1000, 1 * 1000, SmartLocationManager.LOCATION_PROVIDER_RESTRICTION_NONE); // init location manager
mLocalTV = (TextView) findViewById(R.id.locationDisplayTV);
mLocationProviderTV = (TextView) findViewById(R.id.locationProviderTV);
mlocationTimeTV = (TextView) findViewById(R.id.locationTimeFetchedTV);
}
protected void onStart() {
super.onStart();
mLocationManager.startLocationFetching();
}
protected void onStop() {
super.onStop();
mLocationManager.abortLocationFetching();
}
@Override
protected void onPause() {
super.onPause();
mLocationManager.pauseLocationFetching();
}
@Override
public void locationFetched(Location mLocal, Location oldLocation, String time, String locationProvider) {
Toast.makeText(getApplication(), "Lat : " + mLocal.getLatitude() + " Lng : " + mLocal.getLongitude(), Toast.LENGTH_LONG).show();
mLocalTV.setText("Lat : " + mLocal.getLatitude() + " Lng : " + mLocal.getLongitude());
mLocationProviderTV.setText(locationProvider);
mlocationTimeTV.setText(time);
}
}
希望它有所帮助,如果您可以提出任何改进建议,请将其发布在git上。谢谢。
对于仅位置检查,您可以使用以下代码。您可以将它放在主要活动的 onStart() 中,如果返回为 false,则显示警报对话框。
private boolean isLocationAccurate()
{
if (Build.VERSION.SDK_INT < Build.VERSION_CODES.KITKAT)
{
String provider = Settings.Secure
.getString(getContentResolver(), Settings.Secure.LOCATION_PROVIDERS_ALLOWED);
if (provider != null && !provider.contains("gps"))
{
return false;
}
}
else
{
try
{
int status = Settings.Secure
.getInt(this.getContentResolver(), Settings.Secure.LOCATION_MODE);
if (status != Settings.Secure.LOCATION_MODE_HIGH_ACCURACY)
{
return false;
}
}
catch (Settings.SettingNotFoundException e)
{
Log.e(TAG, e.getMessage());
}
}
return true;
}
我使用FusedLocationProviderClient
获得了非常准确的位置
(需要 Google Play 服务)
所需权限
android.permission.ACCESS_FINE_LOCATION
android.permission.ACCESS_COARSE_LOCATION
依赖
'com.google.android.gms:play-services-location:15.0.0'
Kotlin 代码
val client = FusedLocationProviderClient(this)
val location = client.lastLocation
location.addOnCompleteListener {
// this is a lambda expression and we get an 'it' iterator to access the 'result'
// it.result.latitude gives the latitude
// it.result.longitude gives the longitude
val geocoder = Geocoder(applicationContext, Locale.getDefault())
val address = geocoder.getFromLocation(it.result.latitude, it.result.longitude, 1)
if (address != null && address.size > 0) {
// Get the current city
city = address[0].locality
}
}
location.addOnFailureListener {
// Some error in getting the location, let's log it
Log.d("xtraces", it.message)
}
如果您正在为 Android 创建新的定位项目,您应该使用新的Google Play定位服务。它更准确,使用更简单。
几年来,我一直致力于开源 GPS 跟踪器项目GpsTracker。我最近更新了它以处理来自 Android、iOS、Windows Phone 和Java ME手机的定期更新。它功能齐全,可以满足您的需求,并拥有MIT 许可证。
GpsTracker 中的 Android 项目使用新的 Google Play 服务,还有两个服务器堆栈(ASP.NET和PHP)允许您跟踪这些手机。
自2020 年 9 月 23 日起play-services-location版本 17.1.0包含FusedLocationProviderClient.getCurrentLocation()方法,这是获取当前位置的推荐且直接的方法:
返回设备上的单个当前位置修复。与返回缓存位置的getLastLocation()不同,此方法可能会导致设备上的活动位置计算。如果可以在合理的时间(几十秒)内确定设备位置,则返回单个新位置,否则返回 null。
有关详细示例,请查看codingjeremy 的答案和 GitHub 上的官方 Android 位置示例 - Current Location (Kotlin)。
2020 年 4 月
获取当前位置并避免 Last Known Location 可空性的完整步骤。
根据官方文档,在以下情况下, Last Known Location可能为Null:
- 位置在设备设置中已关闭。因为它清除了缓存。
- 该设备从未记录其位置。(新设备)
- 设备上的 Google Play 服务已重新启动。
在这种情况下,您应该requestLocationUpdates并在LocationCallback上接收新位置。
通过以下步骤,您的最后一个已知位置永远不会为空。
先决条件: EasyPermission 库
第 1 步:在清单文件中添加此权限
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
第2步:
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_main)
//Create location callback when it's ready.
createLocationCallback()
//createing location request, how mant request would be requested.
createLocationRequest()
//Build check request location setting request
buildLocationSettingsRequest()
//FusedLocationApiClient which includes location
mFusedLocationClient = LocationServices.getFusedLocationProviderClient(this)
//Location setting client
mSettingsClient = LocationServices.getSettingsClient(this)
//Check if you have ACCESS_FINE_LOCATION permission
if (!EasyPermissions.hasPermissions(
this@MainActivity,
Manifest.permission.ACCESS_FINE_LOCATION)) {
requestPermissionsRequired()
}
else{
//If you have the permission we should check location is opened or not
checkLocationIsTurnedOn()
}
}
第 3 步:创建要在onCreate()中调用的所需函数
private fun requestPermissionsRequired() {
EasyPermissions.requestPermissions(
this,
getString(R.string.location_is_required_msg),
LOCATION_REQUEST,
Manifest.permission.ACCESS_FINE_LOCATION
)
}
private fun createLocationCallback() {
//Here the location will be updated, when we could access the location we got result on this callback.
mLocationCallback = object : LocationCallback() {
override fun onLocationResult(locationResult: LocationResult) {
super.onLocationResult(locationResult)
mCurrentLocation = locationResult.lastLocation
}
}
}
private fun buildLocationSettingsRequest() {
val builder = LocationSettingsRequest.Builder()
builder.addLocationRequest(mLocationRequest!!)
mLocationSettingsRequest = builder.build()
builder.setAlwaysShow(true)
}
private fun createLocationRequest() {
mLocationRequest = LocationRequest.create()
mLocationRequest!!.interval = 0
mLocationRequest!!.fastestInterval = 0
mLocationRequest!!.numUpdates = 1
mLocationRequest!!.priority = LocationRequest.PRIORITY_HIGH_ACCURACY
}
public fun checkLocationIsTurnedOn() { // Begin by checking if the device has the necessary location settings.
mSettingsClient!!.checkLocationSettings(mLocationSettingsRequest)
.addOnSuccessListener(this) {
Log.i(TAG, "All location settings are satisfied.")
startLocationUpdates()
}
.addOnFailureListener(this) { e ->
val statusCode = (e as ApiException).statusCode
when (statusCode) {
LocationSettingsStatusCodes.RESOLUTION_REQUIRED -> {
try {
val rae = e as ResolvableApiException
rae.startResolutionForResult(this@MainActivity, LOCATION_IS_OPENED_CODE)
} catch (sie: IntentSender.SendIntentException) {
}
}
LocationSettingsStatusCodes.SETTINGS_CHANGE_UNAVAILABLE -> {
mRequestingLocationUpdates = false
}
}
}
}
private fun startLocationUpdates() {
mFusedLocationClient!!.requestLocationUpdates(
mLocationRequest,
mLocationCallback, null
)
}
第4步:
在确保打开位置或用户接受打开位置后处理onActivityResult()中的回调。
override fun onActivityResult(requestCode: Int, resultCode: Int, data: Intent?) {
super.onActivityResult(requestCode, resultCode, data)
when (requestCode) {
LOCATION_IS_OPENED_CODE -> {
if (resultCode == AppCompatActivity.RESULT_OK) {
Log.d(TAG, "Location result is OK")
} else {
activity?.finish()
}
}
}
第 5 步:从 FusedClientApi 获取最后一个已知位置
override fun onMapReady(map: GoogleMap) {
mMap = map
mFusedLocationClient.lastLocation.addOnSuccessListener {
if(it!=null){
locateUserInMap(it)
}
}
}
private fun locateUserInMap(location: Location) {
showLocationSafetyInformation()
if(mMap!=null){
val currentLocation = LatLng(location.latitude,location.longitude )
addMarker(currentLocation)
}
}
private fun addMarker(currentLocation: LatLng) {
val cameraUpdate = CameraUpdateFactory.newLatLng(currentLocation)
mMap?.clear()
mMap?.addMarker(
MarkerOptions().position(currentLocation)
.title("Current Location")
)
mMap?.moveCamera(cameraUpdate)
mMap?.animateCamera(cameraUpdate)
mMap?.setMinZoomPreference(14.0f);
}
我希望这会有所帮助。
快乐编码
我会推荐使用Smart Location Library
使用起来非常简单,它很好地包装了位置逻辑。
启动定位服务:
SmartLocation.with(context).location()
.start(new OnLocationUpdatedListener() { ... });
如果您只想获得一个位置(不是周期性的),您可以使用 oneFix 修饰符。例子:
SmartLocation.with(context).location()
.oneFix()
.start(new OnLocationUpdatedListener() { ... });
我已经发布了一个小库,可以很容易地在 Android 中获取位置数据,它甚至可以处理 Android M 运行时权限。
您可以在此处查看:https ://github.com/julioromano/RxLocation并将其或其源代码用作您的实施示例。
在 On Location 方法中简单查找写入代码
public void onLocationChanged(Location 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_RED));
mCurrLocationMarker = mMap.addMarker(markerOptions);
//move map camera
mMap.moveCamera(CameraUpdateFactory.newLatLng(latLng));
mMap.animateCamera(CameraUpdateFactory.zoomTo(18));
PolylineOptions pOptions = new PolylineOptions()
.width(5)
.color(Color.GREEN)
.geodesic(true);
for (int z = 0; z < routePoints.size(); z++) {
LatLng point = routePoints.get(z);
pOptions.add(point);
}
line = mMap.addPolyline(pOptions);
routePoints.add(latLng);
}
获取位置的最佳方法如下
// put dependancy
implementation 'com.google.android.gms:play-services-location:11.0.4'
// PUT permissions in Menifest
<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
// create a Java file as below
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);
if (ActivityCompat.checkSelfPermission(context, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED &&
ActivityCompat.checkSelfPermission(context, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
return;
}
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;
}
}
}
// FILE FINISHED
// FETCH LOCATION FROM ACTIVITY AS BELOW
public void getLocation(Context context) {
MyApplication.log(LOG_TAG, "getLocation() ");
SingleShotLocationProvider.requestSingleUpdate(context,
new SingleShotLocationProvider.LocationCallback() {
@Override
public void onNewLocationAvailable(SingleShotLocationProvider.GPSCoordinates loc) {
location = loc;
MyApplication.log(LOG_TAG, "getLocation() LAT: " + location.latitude + ", LON: " + location.longitude);
}
});
}