这个问题可能有点复杂，但我尽力解释它。
基本上我正在尝试使用我的应用程序获取最后一个位置（lat，long），所以我做了类似这样的事情：
public class GoogleLocation extends Activity implements GoogleApiClient.ConnectionCallbacks, GoogleApiClient.OnConnectionFailedListener, LocationListener {
GoogleApiClient mGoogleApiClient = null;
Location mLastLocation = null;
LocationManager lm;
Double latitude;
Double longitude;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
connectLocation();
}
@Override
public void onConnected(@Nullable Bundle bundle) {
lm = (LocationManager) getSystemService(LOCATION_SERVICE);
if (ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
if (ContextCompat.checkSelfPermission(this, android.Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
ActivityCompat.requestPermissions(this, new String[]{android.Manifest.permission.ACCESS_COARSE_LOCATION},
30);
}
}
Location location = lm.getLastKnownLocation(LocationManager.GPS_PROVIDER);
if(location != null){
longitude = location.getLongitude();
latitude = location.getLatitude();
}
Log.d("IMHERE","IMHERE");
Log.d("latitude",String.valueOf(latitude));
final LocationListener locationListener = new LocationListener() {
public void onLocationChanged(Location location) {
longitude = location.getLongitude();
latitude = location.getLatitude();
//Log.d("latitudee",String.valueOf(latitude));
}
@Override
public void onStatusChanged(String provider, int status, Bundle extras) {
}
@Override
public void onProviderEnabled(String provider) {
}
@Override
public void onProviderDisabled(String provider) {
}
};
lm.requestLocationUpdates(LocationManager.GPS_PROVIDER, 2000, 10, locationListener);
}
protected void onStart() {
mGoogleApiClient.connect();
super.onStart();
}
protected void onStop() {
mGoogleApiClient.disconnect();
super.onStop();
}
@Override
public void onConnectionSuspended(int i) {
}
@Override
public void onConnectionFailed(@NonNull ConnectionResult connectionResult) {
}
public void connectLocation(){
if (mGoogleApiClient == null) {
mGoogleApiClient = new GoogleApiClient.Builder(this)
.addApi(LocationServices.API)
.addConnectionCallbacks(this)
.addOnConnectionFailedListener(this).build();
mGoogleApiClient.connect();
LocationRequest locationRequest = LocationRequest.create();
locationRequest.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY);
locationRequest.setInterval(30 * 1000);
locationRequest.setFastestInterval(5 * 1000);
LocationSettingsRequest.Builder builder = new LocationSettingsRequest.Builder()
.addLocationRequest(locationRequest);
//**************************
builder.setAlwaysShow(true); //this is the key ingredient
//**************************
PendingResult<LocationSettingsResult> result =
LocationServices.SettingsApi.checkLocationSettings(mGoogleApiClient, builder.build());
result.setResultCallback(new ResultCallback<LocationSettingsResult>() {
@Override
public void onResult(LocationSettingsResult result) {
final Status status = result.getStatus();
final LocationSettingsStates state = result.getLocationSettingsStates();
switch (status.getStatusCode()) {
case LocationSettingsStatusCodes.SUCCESS:
break;
case LocationSettingsStatusCodes.RESOLUTION_REQUIRED:
// Location settings are not satisfied. But could be fixed by showing the user
// a dialog.
try {
// Show the dialog by calling startResolutionForResult(),
// and check the result in onActivityResult().
status.startResolutionForResult(
GoogleLocation.this, 1000);
} catch (IntentSender.SendIntentException e) {
// Ignore the error.
}
break;
case LocationSettingsStatusCodes.SETTINGS_CHANGE_UNAVAILABLE:
// Location settings are not satisfied. However, we have no way to fix the
// settings so we won't show the dialog.
break;
}
}
});
}
}
@Override
public void onLocationChanged(Location location) {
mLastLocation = location;
Log.d("mLastLocation",String.valueOf(location.getLatitude()));
}
@Override
public void onStatusChanged(String provider, int status, Bundle extras) {
}
@Override
public void onProviderEnabled(String provider) {
}
@Override
public void onProviderDisabled(String provider) {
}
}
只有通过onLocationChanged才能正常工作，所以第一次进入它需要几秒钟才能获得该位置，第二次尝试时，我的应用程序已经到达最后一个位置，需要10秒才能到达新的位置。
此时一切都很好。
现在我要做的是在后台运行这个，这就是为什么我将extends更改为activity，并在后台尝试使用onLocationChanged来更新我的位置。
类似于this example。
每次我的应用程序检测到新位置时，我都想更新（在我的课程中执行setLocation或其他任何操作）。
正如我所说的，每次启动我的应用程序时都要这样做，这应该在后台运行，每次我访问这个类时它应该检索我的最后一个位置，我想从不同的位置访问这个类。
我的完整代码：
public class GoogleLocation extends Activity implements GoogleApiClient.ConnectionCallbacks, GoogleApiClient.OnConnectionFailedListener, LocationListener {
GoogleApiClient mGoogleApiClient = null;
Location mLastLocation = null;
LocationManager lm;
Double latitude;
Double longitude;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
connectLocation();
}
@Override
public void onConnected(@Nullable Bundle bundle) {
lm = (LocationManager) getSystemService(LOCATION_SERVICE);
if (ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
if (ContextCompat.checkSelfPermission(this, android.Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
ActivityCompat.requestPermissions(this, new String[]{android.Manifest.permission.ACCESS_COARSE_LOCATION},
30);
}
}
Location location = lm.getLastKnownLocation(LocationManager.GPS_PROVIDER);
if(location != null){
longitude = location.getLongitude();
latitude = location.getLatitude();
}
Log.d("IMHERE","IMHERE");
Log.d("latitude",String.valueOf(latitude));
final LocationListener locationListener = new LocationListener() {
public void onLocationChanged(Location location) {
longitude = location.getLongitude();
latitude = location.getLatitude();
//Log.d("latitudee",String.valueOf(latitude));
}
@Override
public void onStatusChanged(String provider, int status, Bundle extras) {
}
@Override
public void onProviderEnabled(String provider) {
}
@Override
public void onProviderDisabled(String provider) {
}
};
lm.requestLocationUpdates(LocationManager.GPS_PROVIDER, 2000, 10, locationListener);
}
protected void onStart() {
mGoogleApiClient.connect();
super.onStart();
}
protected void onStop() {
mGoogleApiClient.disconnect();
super.onStop();
}
@Override
public void onConnectionSuspended(int i) {
}
@Override
public void onConnectionFailed(@NonNull ConnectionResult connectionResult) {
}
public void connectLocation(){
if (mGoogleApiClient == null) {
mGoogleApiClient = new GoogleApiClient.Builder(this)
.addApi(LocationServices.API)
.addConnectionCallbacks(this)
.addOnConnectionFailedListener(this).build();
mGoogleApiClient.connect();
LocationRequest locationRequest = LocationRequest.create();
locationRequest.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY);
locationRequest.setInterval(30 * 1000);
locationRequest.setFastestInterval(5 * 1000);
LocationSettingsRequest.Builder builder = new LocationSettingsRequest.Builder()
.addLocationRequest(locationRequest);
//**************************
builder.setAlwaysShow(true); //this is the key ingredient
//**************************
PendingResult<LocationSettingsResult> result =
LocationServices.SettingsApi.checkLocationSettings(mGoogleApiClient, builder.build());
result.setResultCallback(new ResultCallback<LocationSettingsResult>() {
@Override
public void onResult(LocationSettingsResult result) {
final Status status = result.getStatus();
final LocationSettingsStates state = result.getLocationSettingsStates();
switch (status.getStatusCode()) {
case LocationSettingsStatusCodes.SUCCESS:
break;
case LocationSettingsStatusCodes.RESOLUTION_REQUIRED:
// Location settings are not satisfied. But could be fixed by showing the user
// a dialog.
try {
// Show the dialog by calling startResolutionForResult(),
// and check the result in onActivityResult().
status.startResolutionForResult(
GoogleLocation.this, 1000);
} catch (IntentSender.SendIntentException e) {
// Ignore the error.
}
break;
case LocationSettingsStatusCodes.SETTINGS_CHANGE_UNAVAILABLE:
// Location settings are not satisfied. However, we have no way to fix the
// settings so we won't show the dialog.
break;
}
}
});
}
}
@Override
public void onLocationChanged(Location location) {
mLastLocation = location;
Log.d("mLastLocation",String.valueOf(location.getLatitude()));
}
@Override
public void onStatusChanged(String provider, int status, Bundle extras) {
}
@Override
public void onProviderEnabled(String provider) {
}
@Override
public void onProviderDisabled(String provider) {
}
}
我该怎么做？
答案 0 :(得分：0)
完整代码：
import android.Manifest;
import android.app.Activity;
import android.app.AlertDialog;
import android.app.ProgressDialog;
import android.content.Context;
import android.content.DialogInterface;
import android.content.Intent;
import android.content.IntentSender;
import android.content.pm.PackageManager;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.location.Criteria;
import android.location.Location;
import com.google.android.gms.location.LocationListener;
import android.location.LocationManager;
import android.media.Image;
import android.os.Bundle;
import android.support.v4.app.ActivityCompat;
import android.support.v4.content.ContextCompat;
import android.support.v4.graphics.drawable.RoundedBitmapDrawable;
import android.support.v4.graphics.drawable.RoundedBitmapDrawableFactory;
import android.support.v7.widget.SearchView;
import android.text.Editable;
import android.text.TextUtils;
import android.text.TextWatcher;
import android.util.Log;
import android.view.View;
import android.widget.AdapterView;
import android.widget.EditText;
import android.widget.ImageView;
import android.widget.LinearLayout;
import android.widget.ListView;
import android.widget.TextView;
import android.widget.Toast;
import com.google.android.gms.common.ConnectionResult;
import com.google.android.gms.common.api.GoogleApiClient;
import com.google.android.gms.common.api.PendingResult;
import com.google.android.gms.common.api.ResultCallback;
import com.google.android.gms.common.api.Status;
import com.google.android.gms.location.LocationCallback;
import com.google.android.gms.location.LocationRequest;
import com.google.android.gms.location.LocationServices;
import com.google.android.gms.location.LocationSettingsRequest;
import com.google.android.gms.location.LocationSettingsResult;
import com.google.android.gms.location.LocationSettingsStates;
import com.google.android.gms.location.LocationSettingsStatusCodes;
import java.text.DecimalFormat;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Comparator;
import static android.location.Criteria.POWER_HIGH;
public class MainActivity extends Activity implements GoogleApiClient.OnConnectionFailedListener,
GoogleApiClient.ConnectionCallbacks, ResultCallback<LocationSettingsResult> ,LocationListener {
Double lat, lng;
GoogleApiClient mGoogleApiClient;
LocationRequest mLocationRequest;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Intent k = getIntent();
if (mGoogleApiClient == null) {
mGoogleApiClient = new GoogleApiClient.Builder(this)
.addConnectionCallbacks(this)
.addOnConnectionFailedListener(this)
.addApi(LocationServices.API)
.build();
} else {
mGoogleApiClient.connect();
}
}
protected LocationRequest createLocationRequest() {
mLocationRequest = new LocationRequest();
mLocationRequest.setInterval(10000);
mLocationRequest.setFastestInterval(5000);
mLocationRequest.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY);
return mLocationRequest;
}
@Override
public void onConnected(Bundle bundle) {
Log.e("Connection", "GOOGLE API Connected");
LocationSettingsRequest.Builder builder = new LocationSettingsRequest.Builder()
.addLocationRequest(createLocationRequest());
PendingResult<LocationSettingsResult> result =
LocationServices.SettingsApi.checkLocationSettings(mGoogleApiClient,
builder.build());
result.setResultCallback(this);
}
protected void getPhoneLocation() {
if (ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
return;
}
LocationServices.FusedLocationApi.requestLocationUpdates(
mGoogleApiClient, mLocationRequest, this);
}
@Override
public void onConnectionSuspended(int i) {
Log.e("Connection","GOOGLE API Suspended");
}
@Override
public void onConnectionFailed(ConnectionResult connectionResult) {
Log.e("Connection","GOOGLE API Failed : " + connectionResult.toString() );
}
@Override
protected void onStart() {
mGoogleApiClient.connect();
super.onStart();
}
@Override
protected void onStop() {
mGoogleApiClient.disconnect();
super.onStop();
}
@Override
public void onResult(LocationSettingsResult locationSettingsResult) {
final Status status = locationSettingsResult.getStatus();
switch (status.getStatusCode()) {
case LocationSettingsStatusCodes.SUCCESS:
if (!(ContextCompat.checkSelfPermission(this, android.Manifest.permission.ACCESS_FINE_LOCATION) ==
PackageManager.PERMISSION_GRANTED &&
ContextCompat.checkSelfPermission(this, android.Manifest.permission.ACCESS_COARSE_LOCATION) ==
PackageManager.PERMISSION_GRANTED)) {
ActivityCompat.requestPermissions(this,
new String[]{Manifest.permission.ACCESS_FINE_LOCATION, Manifest.permission.ACCESS_COARSE_LOCATION},
222);
}
else
{
getPhoneLocation();
}
// All location settings are satisfied. The client can
// initialize location requests here.
break;
case LocationSettingsStatusCodes.RESOLUTION_REQUIRED:
// Location settings are not satisfied, but this can be fixed
// by showing the user a dialog.
try {
// Show the dialog by calling startResolutionForResult(),
// and check the result in onActivityResult().
status.startResolutionForResult(
MainActivity.this,
111);
} catch (IntentSender.SendIntentException e) {
// Ignore the error.
}
break;
case LocationSettingsStatusCodes.SETTINGS_CHANGE_UNAVAILABLE:
// Location settings are not satisfied. However, we have no way
// to fix the settings so we won't show the dialog.
break;
}
}
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
Log.e("Activity","Result");
if(requestCode != 333) {
if (!(ContextCompat.checkSelfPermission(this, android.Manifest.permission.ACCESS_FINE_LOCATION) ==
PackageManager.PERMISSION_GRANTED &&
ContextCompat.checkSelfPermission(this, android.Manifest.permission.ACCESS_COARSE_LOCATION) ==
PackageManager.PERMISSION_GRANTED)) {
ActivityCompat.requestPermissions(this,
new String[]{Manifest.permission.ACCESS_FINE_LOCATION, Manifest.permission.ACCESS_COARSE_LOCATION},
222);
} else {
getPhoneLocation();
}
}
else
{
if(resultCode == RESULT_OK) {
finish();
}
}
}
@Override
public void onRequestPermissionsResult(int requestCode, String[] permissions, int[] grantResults) {
if(requestCode == 222) {
if (grantResults.length != 0) {
getPhoneLocation();
}
}
}
@Override
public void onLocationChanged(Location location) {
lat = location.getLatitude();
lng = location.getLongitude();
}
} `
此代码可让您在10到5秒的时间间隔内找到它们并通过onLocationChanged ... GetLastKnowLocation可以获取设备的最后一个已知位置...所以有时候它会返回null ...
CODE EXPLANATION
OnCreate中的此代码块连接到Google API客户端，回调指向活动。
if (mGoogleApiClient == null) {
mGoogleApiClient = new GoogleApiClient.Builder(this)
.addConnectionCallbacks(this)
.addOnConnectionFailedListener(this)
.addApi(LocationServices.API)
.build();
} else {
mGoogleApiClient.connect();
}
这是重要的
public class MainActivity extends Activity implements GoogleApiClient.OnConnectionFailedListener,
GoogleApiClient.ConnectionCallbacks, ResultCallback<LocationSettingsResult> ,LocationListener {
按时间间隔
创建与您的位置请求相同的位置请求protected LocationRequest createLocationRequest() {
mLocationRequest = new LocationRequest();
mLocationRequest.setInterval(10000);
mLocationRequest.setFastestInterval(5000);
mLocationRequest.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY);
return mLocationRequest;
}
当GOOGLE API连接检查设置和权限时
@Override
public void onConnected(Bundle bundle) {
Log.e("Connection", "GOOGLE API Connected");
LocationSettingsRequest.Builder builder = new LocationSettingsRequest.Builder()
.addLocationRequest(createLocationRequest());
PendingResult<LocationSettingsResult> result =
LocationServices.SettingsApi.checkLocationSettings(mGoogleApiClient,
builder.build());
result.setResultCallback(this);
}
设置回复返回此处的活动 在这个块中，我们检查设置的状态，看看它们是否成功返回我们检查权限...如果我们有权访问该位置...那么我们getPhoneLocation（）选项A ..如果我们没有获得许可，我们会要求获得许可，回调将转到选项B
`@Override`
public void onResult(LocationSettingsResult locationSettingsResult) {
final Status status = locationSettingsResult.getStatus();
switch (status.getStatusCode()) {
case LocationSettingsStatusCodes.SUCCESS:
if (!(ContextCompat.checkSelfPermission(this, android.Manifest.permission.ACCESS_FINE_LOCATION) ==
PackageManager.PERMISSION_GRANTED &&
ContextCompat.checkSelfPermission(this, android.Manifest.permission.ACCESS_COARSE_LOCATION) ==
PackageManager.PERMISSION_GRANTED)) {
ActivityCompat.requestPermissions(this,
new String[]{Manifest.permission.ACCESS_FINE_LOCATION, Manifest.permission.ACCESS_COARSE_LOCATION},
222);
}
else
{
getPhoneLocation();
}
// All location settings are satisfied. The client can
// initialize location requests here.
break;
case LocationSettingsStatusCodes.RESOLUTION_REQUIRED:
// Location settings are not satisfied, but this can be fixed
// by showing the user a dialog.
try {
// Show the dialog by calling startResolutionForResult(),
// and check the result in onActivityResult().
status.startResolutionForResult(
MainActivity.this,
111);
} catch (IntentSender.SendIntentException e) {
// Ignore the error.
}
break;
case LocationSettingsStatusCodes.SETTINGS_CHANGE_UNAVAILABLE:
// Location settings are not satisfied. However, we have no way
// to fix the settings so we won't show the dialog.
break;
}
}
选项B 在这个块中，我们从检查用户权限获得Return ...如果他接受了位置请求，我们继续获取PhoneLocation ...如果没有我们关闭活动。
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
Log.e("Activity","Result");
if(requestCode != 333) {
if (!(ContextCompat.checkSelfPermission(this, android.Manifest.permission.ACCESS_FINE_LOCATION) ==
PackageManager.PERMISSION_GRANTED &&
ContextCompat.checkSelfPermission(this, android.Manifest.permission.ACCESS_COARSE_LOCATION) ==
PackageManager.PERMISSION_GRANTED)) {
ActivityCompat.requestPermissions(this,
new String[]{Manifest.permission.ACCESS_FINE_LOCATION, Manifest.permission.ACCESS_COARSE_LOCATION},
222);
} else {
getPhoneLocation();
}
}
else
{
if(resultCode == RESULT_OK) {
finish();
}
}
}
添加位置请求（选项A ）
protected void getPhoneLocation() {
if (ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
return;
}
LocationServices.FusedLocationApi.requestLocationUpdates(
mGoogleApiClient, mLocationRequest, this);
}
现在你有位置 现在，只要活动处于打开状态，您就可以在给定的时间间隔内获得位置。
@Override
public void onLocationChanged(Location location) {
lat = location.getLatitude();
lng = location.getLongitude();
}