要求：
1.有时（不是每次）我得到纬度和经度0.0。
2.我想知道在用户从设置启用gps后如何更新位置。
这是我的代码
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 lat/long 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/wifi enabled
* @return boolean
* */
public boolean canGetLocation() {
return this.canGetLocation;
}
/**
* Function to show settings alert dialog
* On pressing Settings button will lauch 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 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 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;
}
}
从我的活动课开始，我这样称呼
gps = new GPSTracker(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();
}
答案 0 :(得分：7)
在http://gabesechansoftware.com/location-tracking/查看我的帖子。你正在使用的代码就是破碎的。永远不应该使用它。您看到的行为是其中一个错误 - 它不处理getLastLocation返回null的情况，即预期的失败。它是由一个知道自己正在做什么的人写的，但几年前它得到了很高的评价，直到今天都让人们感到沮丧。
答案 1 :(得分：3)
Don，t忘记将服务放在清单文件中
<service
android:name"your package name.GPSTracker"
android:enabled="true" >
</service>
link for Reference，请尝试此链接
答案 2 :(得分：2)
我创建了一个教程，使用位置管理器获取当前的纬度和经度。在此处下载源代码（Get Current Location Using Background Service）
<强> MainActivity.java
package servicetutorial.service;
import android.*;
import android.app.Activity;
import android.app.ActivityManager;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.content.SharedPreferences;
import android.content.pm.PackageManager;
import android.location.Address;
import android.location.Geocoder;
import android.preference.PreferenceManager;
import android.renderscript.Double2;
import android.support.v4.app.ActivityCompat;
import android.support.v4.content.ContextCompat;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;
import android.widget.Toast;
import java.io.IOException;
import java.util.List;
import java.util.Locale;
public class MainActivity extends Activity {
Button btn_start;
private static final int REQUEST_PERMISSIONS = 100;
boolean boolean_permission;
TextView tv_latitude, tv_longitude, tv_address,tv_area,tv_locality;
SharedPreferences mPref;
SharedPreferences.Editor medit;
Double latitude,longitude;
Geocoder geocoder;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
btn_start = (Button) findViewById(R.id.btn_start);
tv_address = (TextView) findViewById(R.id.tv_address);
tv_latitude = (TextView) findViewById(R.id.tv_latitude);
tv_longitude = (TextView) findViewById(R.id.tv_longitude);
tv_area = (TextView)findViewById(R.id.tv_area);
tv_locality = (TextView)findViewById(R.id.tv_locality);
geocoder = new Geocoder(this, Locale.getDefault());
mPref = PreferenceManager.getDefaultSharedPreferences(getApplicationContext());
medit = mPref.edit();
btn_start.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
if (boolean_permission) {
if (mPref.getString("service", "").matches("")) {
medit.putString("service", "service").commit();
Intent intent = new Intent(getApplicationContext(), GoogleService.class);
startService(intent);
} else {
Toast.makeText(getApplicationContext(), "Service is already running", Toast.LENGTH_SHORT).show();
}
} else {
Toast.makeText(getApplicationContext(), "Please enable the gps", Toast.LENGTH_SHORT).show();
}
}
});
fn_permission();
}
private void fn_permission() {
if ((ContextCompat.checkSelfPermission(getApplicationContext(), android.Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED)) {
if ((ActivityCompat.shouldShowRequestPermissionRationale(MainActivity.this, android.Manifest.permission.ACCESS_FINE_LOCATION))) {
} else {
ActivityCompat.requestPermissions(MainActivity.this, new String[]{android.Manifest.permission.ACCESS_FINE_LOCATION
},
REQUEST_PERMISSIONS);
}
} else {
boolean_permission = true;
}
}
@Override
public void onRequestPermissionsResult(int requestCode, String[] permissions, int[] grantResults) {
super.onRequestPermissionsResult(requestCode, permissions, grantResults);
switch (requestCode) {
case REQUEST_PERMISSIONS: {
if (grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
boolean_permission = true;
} else {
Toast.makeText(getApplicationContext(), "Please allow the permission", Toast.LENGTH_LONG).show();
}
}
}
}
private BroadcastReceiver broadcastReceiver = new BroadcastReceiver() {
@Override
public void onReceive(Context context, Intent intent) {
latitude = Double.valueOf(intent.getStringExtra("latutide"));
longitude = Double.valueOf(intent.getStringExtra("longitude"));
List<Address> addresses = null;
try {
addresses = geocoder.getFromLocation(latitude, longitude, 1);
String cityName = addresses.get(0).getAddressLine(0);
String stateName = addresses.get(0).getAddressLine(1);
String countryName = addresses.get(0).getAddressLine(2);
tv_area.setText(addresses.get(0).getAdminArea());
tv_locality.setText(stateName);
tv_address.setText(countryName);
} catch (IOException e1) {
e1.printStackTrace();
}
tv_latitude.setText(latitude+"");
tv_longitude.setText(longitude+"");
tv_address.getText();
}
};
@Override
protected void onResume() {
super.onResume();
registerReceiver(broadcastReceiver, new IntentFilter(GoogleService.str_receiver));
}
@Override
protected void onPause() {
super.onPause();
unregisterReceiver(broadcastReceiver);
}
}
<强> GoogleService.java
package servicetutorial.service;
import android.app.Service;
import android.content.Context;
import android.content.Intent;
import android.location.Location;
import android.location.LocationListener;
import android.location.LocationManager;
import android.os.Bundle;
import android.os.Handler;
import android.os.IBinder;
import android.support.annotation.Nullable;
import android.util.Log;
import java.util.Timer;
import java.util.TimerTask;
/**
*由deepshikha于24/11/16创建。 * /
public class GoogleService extends Service implements LocationListener{
boolean isGPSEnable = false;
boolean isNetworkEnable = false;
double latitude,longitude;
LocationManager locationManager;
Location location;
private Handler mHandler = new Handler();
private Timer mTimer = null;
long notify_interval = 1000;
public static String str_receiver = "servicetutorial.service.receiver";
Intent intent;
public GoogleService() {
}
@Nullable
@Override
public IBinder onBind(Intent intent) {
return null;
}
@Override
public void onCreate() {
super.onCreate();
mTimer = new Timer();
mTimer.schedule(new TimerTaskToGetLocation(),5,notify_interval);
intent = new Intent(str_receiver);
}
@Override
public void onLocationChanged(Location location) {
}
@Override
public void onStatusChanged(String provider, int status, Bundle extras) {
}
@Override
public void onProviderEnabled(String provider) {
}
@Override
public void onProviderDisabled(String provider) {
}
private void fn_getlocation(){
locationManager = (LocationManager)getApplicationContext().getSystemService(LOCATION_SERVICE);
isGPSEnable = locationManager.isProviderEnabled(LocationManager.GPS_PROVIDER);
isNetworkEnable = locationManager.isProviderEnabled(LocationManager.NETWORK_PROVIDER);
if (!isGPSEnable && !isNetworkEnable){
}else {
if (isNetworkEnable){
location = null;
locationManager.requestLocationUpdates(LocationManager.NETWORK_PROVIDER,1000,0,this);
if (locationManager!=null){
location = locationManager.getLastKnownLocation(LocationManager.NETWORK_PROVIDER);
if (location!=null){
Log.e("latitude",location.getLatitude()+"");
Log.e("longitude",location.getLongitude()+"");
latitude = location.getLatitude();
longitude = location.getLongitude();
fn_update(location);
}
}
}
if (isGPSEnable){
location = null;
locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER,1000,0,this);
if (locationManager!=null){
location = locationManager.getLastKnownLocation(LocationManager.GPS_PROVIDER);
if (location!=null){
Log.e("latitude",location.getLatitude()+"");
Log.e("longitude",location.getLongitude()+"");
latitude = location.getLatitude();
longitude = location.getLongitude();
fn_update(location);
}
}
}
}
}
private class TimerTaskToGetLocation extends TimerTask{
@Override
public void run() {
mHandler.post(new Runnable() {
@Override
public void run() {
fn_getlocation();
}
});
}
}
private void fn_update(Location location){
intent.putExtra("latutide",location.getLatitude()+"");
intent.putExtra("longitude",location.getLongitude()+"");
sendBroadcast(intent);
}
}
答案 3 :(得分：0)
我找到了一个非常简单和流畅的解决方案： 请按照以下步骤操作以获取您的当前位置，这很容易 ，请放心，我已经对其进行了测试并可以完美
实现“ com.google.android.gms：play-services-location：15.0.1”
在清单文件中添加这2个权限
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION"/>
将此代码段添加到您的类MainActivity中：
公共类MainActivity扩展了活动实现了LocationListener {
LocationManager locationManager;
String provider;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
if (ActivityCompat.checkSelfPermission(this,
Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
// Check Permissions Now
ActivityCompat.requestPermissions(this,
new String[] { Manifest.permission.ACCESS_FINE_LOCATION },
0);
}
// Getting LocationManager object
statusCheck();
locationManager = (LocationManager) getSystemService(
Context.LOCATION_SERVICE);
// Creating an empty criteria object
Criteria criteria = new Criteria();
// Getting the name of the provider that meets the criteria
provider = locationManager.getBestProvider(criteria, false);
if (provider != null && !provider.equals("")) {
if (!provider.contains("gps")) { // if gps is disabled
final Intent poke = new Intent();
poke.setClassName("com.android.settings",
"com.android.settings.widget.SettingsAppWidgetProvider");
poke.addCategory(Intent.CATEGORY_ALTERNATIVE);
poke.setData(Uri.parse("3"));
sendBroadcast(poke);
}
// Get the location from the given provider
Location location = locationManager
.getLastKnownLocation(LocationManager.NETWORK_PROVIDER);
locationManager.requestLocationUpdates(
LocationManager.NETWORK_PROVIDER, 500, 0, this);
if (location != null)
onLocationChanged(location);
else
location = locationManager.getLastKnownLocation(provider);
if (location != null)
onLocationChanged(location);
else
Toast.makeText(getBaseContext(), "Location can't be retrieved",
Toast.LENGTH_SHORT).show();
} else {
Toast.makeText(getBaseContext(), "No Provider Found",
Toast.LENGTH_SHORT).show();
}
}
public void statusCheck() {
final LocationManager manager = (LocationManager) getSystemService(
Context.LOCATION_SERVICE);
if (!manager.isProviderEnabled(LocationManager.GPS_PROVIDER)) {
buildAlertMessageNoGps();
}
}
private void buildAlertMessageNoGps() {
final AlertDialog.Builder builder = new AlertDialog.Builder(this);
builder.setMessage(
"Your GPS seems to be disabled, do you want to enable it?")
.setCancelable(false).setPositiveButton("Yes",
new DialogInterface.OnClickListener() {
public void onClick(final DialogInterface dialog,
final int id) {
startActivity(new Intent(
android.provider.Settings.ACTION_LOCATION_SOURCE_SETTINGS));
}
})
.setNegativeButton("No", new DialogInterface.OnClickListener() {
public void onClick(final DialogInterface dialog,
final int id) {
dialog.cancel();
}
});
final AlertDialog alert = builder.create();
alert.show();
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
/* getMenuInflater().inflate(R.menu.activity_main, menu); */
return true;
}
@Override
public void onLocationChanged(Location location) {
// Getting reference to TextView tv_longitude
TextView tvLongitude = (TextView) findViewById(R.id.tv_longitude);
// Getting reference to TextView tv_latitude
TextView tvLatitude = (TextView) findViewById(R.id.tv_latitude);
// Setting Current Longitude
tvLongitude.setText("Longitude:" + location.getLongitude());
// Setting Current Latitude
tvLatitude.setText("Latitude:" + location.getLatitude());
}
@Override
public void onProviderDisabled(String provider) {
// TODO Auto-generated method stub
if (ActivityCompat.checkSelfPermission(this,
Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
// Check Permissions Now
ActivityCompat.requestPermissions(this,
new String[] { Manifest.permission.ACCESS_FINE_LOCATION },
0);
}
}
@Override
public void onProviderEnabled(String provider) {
// TODO Auto-generated method stub
}
@Override
public void onStatusChanged(String provider, int status, Bundle extras) {
// TODO Auto-generated method stub
}
}
将此添加到您的activity_main.xml
<TextView
android:id="@+id/tv_location"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerHorizontal="true"
android:text="current location"
android:textStyle="bold" />
<TextView
android:id="@+id/tv_longitude"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="@id/tv_location"
android:layout_centerHorizontal="true" />
<TextView
android:id="@+id/tv_latitude"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="@id/tv_longitude"
android:layout_centerHorizontal="true" />