在手机锁定时获取用户在Android中的位置

Question

我正在寻找一种解决方案，以便在Android API 17（Android 4.2）中以及手机锁定时的特定时间间隔内获取用户的位置。

我已经尝试了一些不同的代码，检查了很多教程，几乎在网上的任何地方都进行了搜索。解决方案可能就在那里，但我认为这是缺乏Android开发经验和解释不同解决方案和方法的结合。

起初我有一些非常基本的代码，当屏幕打开时效果非常好。即使在后台，位置也得到了更新（因为我可以通过经度和纬度的Toast消息进行检查）。 我使用Handler来执行此操作：

    public void locationRunnable() {
    final Handler locationHandler = new Handler();
    final int distanceDelay = 5000; // milliseconds

    locationHandler.postDelayed(new Runnable(){
        public void run() {
            // code
            mMap.clear();

            if (ActivityCompat.checkSelfPermission(this, android.Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(this, android.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;
            }

            mMap.setMyLocationEnabled(true);
            mMap.setBuildingsEnabled(true);
            mMap.getUiSettings().setMyLocationButtonEnabled(false);

            LocationManager locationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
            Criteria criteria = new Criteria();
            String provider = locationManager.getBestProvider(criteria, true);

            myLocation = locationManager.getLastKnownLocation(provider);

            if (myLocation != null) {
                latitudeCurrentPosition = myLocation.getLatitude();
                longitudeCurrentPosition = myLocation.getLongitude();
            }

            currentPattern = shortTest;
            Notification.Builder notificationBuilderChecking = new Notification.Builder(this)
                    .setSmallIcon(R.mipmap.ic_launcher)
                    .setLargeIcon(BitmapFactory.decodeResource(getResources(), R.mipmap.ic_launcher))
                    .setContentTitle("Test app")
                    .setAutoCancel(true)
                    .setOnlyAlertOnce(false)
                    .setContentText("Getting location!")
                    .setPriority(Notification.PRIORITY_MAX)
                    .setLights(0xffffffff, 200, 200)
                    .setVibrate(currentPattern);

            Notification notification2 = notificationBuilderChecking.build();

            NotificationManager notificationMngr2 = (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);
            notificationMngr2.notify(NOTIFICATION_ID, notification2);

            locationHandler.postDelayed(this, distanceDelay);
        }

    }, distanceDelay);

}

它只是一个片段，目的是在后台，当屏幕被锁定时，这将每10秒循环一次。确实如此。即使手机被锁定，但仅约3次。定时器上升3次后手机振动频率降低（打瞌睡功能？）。 此外，手机确实振动，但位置没有更新。当我在前台使用应用程序解锁手机时，位置仍在我锁定手机的位置。过了一会儿（10秒），它会更新。我在地图上用标记来检查。

再次说明：当手机解锁时，它可以正常工作。

现在我尝试使用服务，服务（意图服务）或广播接收器，并开始新的线程，但我不知道如何工作，什么都没有。

我的最后一些代码包含一个无效的广播接收器，最新的代码包含一个AlarmManager：

    public void getLocation(Context context) {

    AlarmManager am = (AlarmManager) context.getSystemService(Context.ALARM_SERVICE);
    Intent intent = new Intent(context, AlarmIntent.class);
    PendingIntent pi = PendingIntent.getBroadcast(context, 0, intent, 0);
    //After after 30 seconds
    am.setRepeating(AlarmManager.ELAPSED_REALTIME_WAKEUP, System.currentTimeMillis(), 10000, pi);


    context.getSystemService(Context.CONNECTIVITY_SERVICE);

    mMap.clear();

    mMap.setMyLocationEnabled(true);
    mMap.getUiSettings().setMyLocationButtonEnabled(false);

    LocationManager locationManager = (LocationManager) context.getSystemService(Context.LOCATION_SERVICE);
    Criteria criteria = new Criteria();
    String provider = locationManager.getBestProvider(criteria, true);

    myLocation = locationManager.getLastKnownLocation(provider);

    latitudeCurrentPosition = myLocation.getLatitude();
    longitudeCurrentPosition = myLocation.getLongitude();

    LatLng latLngCurrent = new LatLng(latitudeCurrentPosition, longitudeCurrentPosition);

    mMap.moveCamera(CameraUpdateFactory.newLatLng(latLngCurrent));
    mMap.animateCamera(CameraUpdateFactory.zoomTo(distZoom));

    currentPattern = shortTest;
    showNotification(context);

    mHereIAm = mMap.addMarker(new MarkerOptions()
            .position(new LatLng(latitudeCurrentPosition, longitudeCurrentPosition))
            .title(weAreHere)
            .draggable(false)
            .icon(BitmapDescriptorFactory
                    .fromResource(R.drawable.marker_iconv3)));
    mHereIAm.setTag(0);
    mHereIAm.showInfoWindow();
}

AndroidManifest权限：

    <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
<uses-permission android:name="android.permission.VIBRATE" />
<uses-permission android:name="android.permission.WAKE_LOCK" />
<uses-permission android:name="com.android.alarm.permission.SET_ALARM" />

但是在10000的时候，Android Studio告诉我＆＃34;从Android 5.1开始，价值将被强制为60000;不要依赖于这一点......＆＃34;因此，AlarmManager也不是很有用。 使用最后一个代码，我的应用程序甚至不再运行了。

但仍然：振动和东西仍然存在，但位置更新不会。

简而言之： 我需要一些基本的（至少，我认为它是如此困难，因为唯一的问题是它在屏幕锁定时无法正常工作）代码，它会更新我的位置，可变间隔。

也许我必须使用Handler / Runnable，启动新线程，使用服务或广播接收器。也许AlarmManager也可以正常工作，但我不知道如何使用和使用。

这是我的第一篇文章。如果有任何遗漏或您需要更多信息，请询问。我试图尽可能精确，而不需要花费太多开销。

修改01 我可以使用工作服务吗？ - 我已将API更新为21，因此我可以使用此服务，但我不知道这是否是我正在寻找的正确解决方案？有一些很棒的教程可以使用它。

编辑02 让我更清楚，更少开销：我正在寻找一种解决方案，以便在设备锁定时获取用户的当前位置：使用API​​，服务，IntentService，BroadcastReceiver，...... - 每个教程告诉我一些不同的东西，即使在Stack Overflow，我也遇到了找到正确解决方案的麻烦。 我能够使用服务以及Intent服务，但由于一些错误，我无法请求任何位置更新，例如： java.lang.RuntimeException: Unable to start activity ComponentInfo{com.name.name/com.name.name.MapsActivity}: java.lang.NullPointerException: Attempt to invoke virtual method 'void com.google.android.gms.maps.GoogleMap.setMyLocationEnabled(b‌​oolean)' on a null object reference - 搜索此错误的解决方案，稍后再给我一个错误，然后打开......我陷入错误循环和许多不必要的代码中。

我希望有一个简单的方法来获取用户的位置，你们可以帮助我。再次感谢。

编辑03 我已按照this tutorial上的说明操作，并且位置正在检查中。请参阅以下代码：

public class LocationService 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 LocationService(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;
            // First get location from Network Provider
            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(LocationService.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;
}

}

我已禁用网络位置，并且仅允许GPS位置进行测试 - 同时进行测试。

我的MapsActivity：

    public void getLocation(){
    gps = new LocationService(MapsActivity.this);
    if(gps.canGetLocation()) { // gps enabled} // return boolean true/false
        latitudeCurrentPosition = gps.getLatitude(); // returns latitude
        longitudeCurrentPosition = gps.getLongitude(); // returns longitude

        latLngCurrent = new LatLng(latitudeCurrentPosition, longitudeCurrentPosition);

        Toast toastLatCur = makeText(getApplicationContext(), "Lat Current: " + latitudeCurrentPosition + "" ,Toast.LENGTH_SHORT);
        toastLatCur.show();

        Toast toastLongCur = makeText(getApplicationContext(), "Long Current: " + longitudeCurrentPosition + "" ,Toast.LENGTH_SHORT);
        toastLongCur.show();
    }

    else {
        gps.showSettingsAlert();
    }

    if(goToLocation){
        mMap.moveCamera(CameraUpdateFactory.newLatLng(latLngCurrent));
        goToLocation = false;

        if(firstStart){
            mMap.animateCamera(CameraUpdateFactory.zoomTo(distZoom));
            firstStart = false;
        }
    }

    vibrateNotification();
}

当屏幕被锁定时，手机会像我在vibrateNotificatoin()中所说的那样振动 - 每10秒完美运行一次。但该位置没有更新！所以服务不是解决这个问题的正确方法。救命啊！

Answer 1

您应该使用服务来执行即使应用程序未运行也需要执行的任务。试一试。

Answer 2

所以，我已经按照一些教程进行了搜索并尝试了更多来找到解决方案：

1. 制作新服务：

package com.name.name;


import android.app.AlertDialog;
import android.app.Notification;
import android.app.NotificationManager;
import android.app.Service;
import android.content.Context;
import android.content.DialogInterface;
import android.content.Intent;
import android.graphics.BitmapFactory;
import android.location.Location;
import android.location.LocationListener;
import android.location.LocationManager;
import android.os.Bundle;
import android.os.IBinder;
import android.provider.Settings;
import android.util.Log;

import static com.name.name.MapsActivity.NOTIFICATION_ID;

public class LocationService 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 LocationService(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;
                // First get location from Network Provider
                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(LocationService.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;
    }

}

1. 每次运行此服务时，使用Handler和Runnable并使用Wakelock：
   in OnCreate：

    PowerManager powerManager = (PowerManager) getSystemService(POWER_SERVICE);
    wakeLock = powerManager.newWakeLock(PowerManager.PARTIAL_WAKE_LOCK,
            "MyWakelockTag");

• 使用LocationService获取所获得的数据。
• 只要您需要数据并使用它执行操作，就启动此功能：

  

public void startDoingStuffWithLocationData（）{

                final Runnable runnable= new Runnable() {
                    public void run() {
                        // do stuff here
                        getLocation();
                        }

                        else {
                            handler.postDelayed(this, 10000);
                        }
                    }
                };
                runnable.run();
            }
    }

• 从服务中获取数据：

  

public void getLocation（）{

    wakeLock.acquire();

    gps = new LocationService(MapsActivity.this);
    if(gps.canGetLocation()) { // gps enabled} // return boolean true/false
        latitudeCurrentPosition = gps.getLatitude(); // returns latitude
        longitudeCurrentPosition = gps.getLongitude(); // returns longitude

        latLngCurrent = new LatLng(latitudeCurrentPosition, longitudeCurrentPosition);
    }

    else {
        gps.showSettingsAlert();
    }

    wakeLock.release();
}

请务必使用release（）函数结束唤醒锁以保护电池。