我想在后台每隔几分钟更新用户的位置。
我使用了此示例代码googlesamples/android-play-location
但将其更改为与Service
public class MyService extends Service implements
GoogleApiClient.ConnectionCallbacks,
GoogleApiClient.OnConnectionFailedListener,
LocationListener, ResultCallback<LocationSettingsResult>
但我无法检查位置设置
protected void checkLocationSettings() {
PendingResult<LocationSettingsResult> result =
LocationServices.SettingsApi.checkLocationSettings(
mGoogleApiClient,
mLocationSettingsRequest
);
result.setResultCallback(this);
}
@Override
public void onResult(LocationSettingsResult locationSettingsResult) {
final Status status = locationSettingsResult.getStatus();
switch (status.getStatusCode()) {
case LocationSettingsStatusCodes.SUCCESS:
Log.i(TAG, "All location settings are satisfied.");
startLocationUpdates();
break;
case LocationSettingsStatusCodes.RESOLUTION_REQUIRED:
Log.i(TAG, "Location settings are not satisfied. Show the user a dialog to" +
"upgrade location settings ");
try {
// Show the dialog by calling startResolutionForResult(), and check the result
// in onActivityResult().
status.startResolutionForResult(MainActivity.this, REQUEST_CHECK_SETTINGS);
} catch (IntentSender.SendIntentException e) {
Log.i(TAG, "PendingIntent unable to execute request.");
}
break;
case LocationSettingsStatusCodes.SETTINGS_CHANGE_UNAVAILABLE:
Log.i(TAG, "Location settings are inadequate, and cannot be fixed here. Dialog " +
"not created.");
break;
}
}
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
switch (requestCode) {
// Check for the integer request code originally supplied to startResolutionForResult().
case REQUEST_CHECK_SETTINGS:
switch (resultCode) {
case Activity.RESULT_OK:
Log.i(TAG, "User agreed to make required location settings changes.");
startLocationUpdates();
break;
case Activity.RESULT_CANCELED:
Log.i(TAG, "User chose not to make required location settings changes.");
break;
}
break;
}
}
因为此方法需要Activity
status.startResolutionForResult（MainActivity.this， REQUEST_CHECK_SETTINGS）;
如果我将前面的代码放在MainActvity中，我就不会引用mGoogleApiClient和mLocationSettingsRequest
LocationServices.SettingsApi.checkLocationSettings（mGoogleApiClient， mLocationSettingsRequest）;
即使活动被破坏，我也希望升级并保存在后台的位置。
使用服务是正确的方法吗？
如何检查位置设置？
[编辑]
我尝试使用PendingIntent和IntentService
LocationServices.FusedLocationApi.requestLocationUpdates(mGoogleApiClient,
mLocationRequest, mPendingIntent);
此方法更适用于后台用例 用于接收位置更新，即使应用程序已被杀死 系统。
与Service和LocationListner的版本相比有什么不同？
答案 0 :(得分：1)
[溶液]
我找到了解决问题的方法
要访问主要活动，我使用了方法
MainActivity.getInstance（）
<强> MainActivity
public class MainActivity extends AppCompatActivity {
private static MainActivity instance;
public static MainActivity getInstance() {
Log.i("MainActivity", "getInstance");
return instance;
}
@Override
protected void onCreate(Bundle savedInstanceState) {
Log.i(TAG, "onCreate");
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
// Instance of the MainActivity
instance = this;
}
...
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
Log.i(TAG, "onActivityResult");
switch (requestCode) {
// Check for the integer request code originally supplied to startResolutionForResult().
case REQUEST_CHECK_SETTINGS:
switch (resultCode) {
case Activity.RESULT_OK:
Log.i(TAG, "User agreed to make required location settings changes.");
startService(intent);
break;
case Activity.RESULT_CANCELED:
Log.i(TAG, "User chose not to make required location settings changes.");
break;
}
break;
}
}
}
<强>服务
@Override
public void onResult(LocationSettingsResult locationSettingsResult) {
final Status status = locationSettingsResult.getStatus();
switch (status.getStatusCode()) {
case LocationSettingsStatusCodes.SUCCESS:
// All location settings are satisfied. The client can
// initialize location requests here.
Log.i(TAG, "All location settings are satisfied.");
startLocationUpdates();
break;
case LocationSettingsStatusCodes.RESOLUTION_REQUIRED:
// Location settings are not satisfied, but this can be fixed
// by showing the user a dialog.
Log.i(TAG, "Location settings are not satisfied. Show the user a dialog to " +
"upgrade location settings ");
try {
// Show the dialog by calling startResolutionForResult(),
// and check the result in onActivityResult().
status.startResolutionForResult(MainActivity.getInstance(), REQUEST_CHECK_SETTINGS);
} catch (IntentSender.SendIntentException e) {
// Ignore the error.
Log.i(TAG, "PendingIntent unable to execute request.");
}
break;
// The status will never be SETTINGS_CHANGE_UNAVAILABLE if use builder.setAlwaysShow(true);
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.
Log.i(TAG, "Location settings are inadequate, and cannot be fixed here. Dialog " +
"not created.");
break;
}
}
答案 1 :(得分：0)
您可以使用位置更改侦听器
public class LocationService extends Service
{
public static final String BROADCAST_ACTION = "Hello World";
private static final int TWO_MINUTES = 1000 * 60 * 2;
public LocationManager locationManager;
public MyLocationListener listener;
public Location previousBestLocation = null;
Intent intent;
int counter = 0;
@Override
public void onCreate()
{
super.onCreate();
intent = new Intent(BROADCAST_ACTION);
}
@Override
public void onStart(Intent intent, int startId)
{
locationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
listener = new MyLocationListener();
locationManager.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, 4000, 0, listener);
locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, 4000, 0, listener);
}
@Override
public IBinder onBind(Intent intent)
{
return null;
}
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);
}
@Override
public void onDestroy() {
// handler.removeCallbacks(sendUpdatesToUI);
super.onDestroy();
Log.v("STOP_SERVICE", "DONE");
locationManager.removeUpdates(listener);
}
public static Thread performOnBackgroundThread(final Runnable runnable) {
final Thread t = new Thread() {
@Override
public void run() {
try {
runnable.run();
} finally {
}
}
};
t.start();
return t;
}
public class MyLocationListener implements LocationListener
{
public void onLocationChanged(final Location loc)
{
Log.i("**************************************", "Location changed");
if(isBetterLocation(loc, previousBestLocation)) {
loc.getLatitude();
loc.getLongitude();
intent.putExtra("Latitude", loc.getLatitude());
intent.putExtra("Longitude", loc.getLongitude());
intent.putExtra("Provider", loc.getProvider());
sendBroadcast(intent);
}
}
public void onProviderDisabled(String provider)
{
Toast.makeText( getApplicationContext(), "Gps Disabled", Toast.LENGTH_SHORT ).show();
}
public void onProviderEnabled(String provider)
{
Toast.makeText( getApplicationContext(), "Gps Enabled", Toast.LENGTH_SHORT).show();
}
public void onStatusChanged(String provider, int status, Bundle extras)
{
}
}
}