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在Android M中获取经度0.0

支铭晨
2023-03-14
问题内容

我遇到的问题是在Android棉花糖(API 23)(即6.0)中将值0.0作为纬度和经度。

我对此进行了很多搜索,但没有找到解决方案。我的代码完全可以用于小于23的其他API版本。

我还为selfPermission放置了代码,所有这些都在起作用,相反,它使我迟到了0.0。

请看看我的追踪方式:

GPSTracker.java

public class GPSTracker extends Service implements LocationListener {

    private  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 = 1000;

    // 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;

    Activity activity;

    public GPSTracker() {
    }

    public GPSTracker(Context context, Activity activity) {
        this.mContext = context;
        this.activity = activity;
        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) {
                    int requestPermissionsCode = 50;
                    if (ContextCompat.checkSelfPermission(activity, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(activity, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
                        ActivityCompat.requestPermissions(activity, new String[]{Manifest.permission.ACCESS_FINE_LOCATION}, requestPermissionsCode);

                    } else {
                        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) {
                        if (ContextCompat.checkSelfPermission(activity, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(activity, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
                            ActivityCompat.requestPermissions(activity, new String[]{Manifest.permission.ACCESS_FINE_LOCATION}, 50);

                        } else {
                            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) {
            if (ContextCompat.checkSelfPermission(activity, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(activity, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
                ActivityCompat.requestPermissions(activity, new String[]{Manifest.permission.ACCESS_FINE_LOCATION}, 50);

            } else {
                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;
    }
 }

DashboardActivity.java:

在onCreate()中,我初始化了GPSTracker:

gps = new GPSTracker(mContext,DashboardActivity.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();
        }

AndroidManifest.xml

<permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
    <permission android:name="android.permission.ACCESS_FINE_LOCATION" />


    <uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
    <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
    <uses-permission android:name="android.permission.INTERNET" />

我已经遍历了Stack Overflow中提供的许多链接,但是它们都没有帮助我解决此问题。

在这里,我将不胜感激。


问题答案:

借助 CommonsWareBlackkara的 答案,我能够解决我的问题。

根据他们的建议,我更改了代码,并通过调试仔细检查了代码的每个步骤。

因此,我遇到了这样的问题:在棉花糖的情况下,我的onLocationChanged()没有被解雇,但是令人惊讶的是,在低于Android
M或6.0的旧设备中,它却被解雇了。

为了解决这个问题,我更改了代码,如下所示,在此发布完整的代码,以便任何有相同问题的人都可以摆脱。

GPSTracker.java

public class GPSTracker extends Service{

    private  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 = 1000; // 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;

    Activity activity;

    public GPSTracker() {
    }

    public GPSTracker(Context context, Activity activity) {
        this.mContext = context;
        this.activity = activity;
        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) {
                    int requestPermissionsCode = 50;

                    locationManager.requestLocationUpdates(
                            LocationManager.NETWORK_PROVIDER,
                            MIN_TIME_BW_UPDATES,
                            MIN_DISTANCE_CHANGE_FOR_UPDATES, mLocationListener);
                    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) {
                    if (ContextCompat.checkSelfPermission(activity, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(activity, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
                        ActivityCompat.requestPermissions(activity, new String[]{Manifest.permission.ACCESS_FINE_LOCATION}, 50);

                    } else {
                        locationManager.requestLocationUpdates(
                                LocationManager.GPS_PROVIDER,
                                MIN_TIME_BW_UPDATES,
                                MIN_DISTANCE_CHANGE_FOR_UPDATES, mLocationListener);
                        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() {

    }


    private final LocationListener mLocationListener = new LocationListener() {
        @Override
        public void onLocationChanged(final Location location) {

            if (location != null) {
                latitude = location.getLatitude();
                longitude = location.getLongitude();
            }
        }

        @Override
        public void onStatusChanged(String provider, int status, Bundle extras) {

        }

        @Override
        public void onProviderEnabled(String provider) {

        }

        @Override
        public void onProviderDisabled(String provider) {

        }
    };

    /**
     * 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 IBinder onBind(Intent arg0) {
        return null;
    }
}

DashboardActivity.java

public class DashboardActivity extends Activity {

    Context mContext;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_dashboard);

        mContext = this;

        if (ContextCompat.checkSelfPermission(mContext, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(mContext, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
            ActivityCompat.requestPermissions(DashboardActivity.this, new String[]{Manifest.permission.ACCESS_FINE_LOCATION}, 1);

        } else {
            Toast.makeText(mContext,"You need have granted permission",Toast.LENGTH_SHORT).show();
            gps = new GPSTracker(mContext, DashboardActivity.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();
            }
        }           
    }


    @Override
    public void onRequestPermissionsResult(int requestCode, String[] permissions, int[] grantResults) {
        super.onRequestPermissionsResult(requestCode, permissions, grantResults);

        switch (requestCode) {
            case 1: {
                // If request is cancelled, the result arrays are empty.
                if (grantResults.length > 0
                        && grantResults[0] == PackageManager.PERMISSION_GRANTED) {

                    // permission was granted, yay! Do the

                    // contacts-related task you need to do.

                    gps = new GPSTracker(mContext, DashboardActivity.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();
                    }

                } else {

                    // permission denied, boo! Disable the
                    // functionality that depends on this permission.

                    Toast.makeText(mContext, "You need to grant permission", Toast.LENGTH_SHORT).show();
                }
                return;
            }
        }
    }
}

Manifest.xml:

添加的权限

    <uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
    <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
    <uses-permission android:name="android.permission.INTERNET" />

在应用程序标签中声明服务:

 <service android:name=".utilities.GPSTracker"/>


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