Question

有没有办法在没有加载地图的情况下在Android上使用google maps v2，我需要在点击按钮时读取gps位置，并计算2点之间的距离，我知道该怎么做但只有在地图已加载，我需要一种没有地图的方法，这可能吗？

Answer 1

您可以在没有地图的情况下获得GPS位置。试试代码

拨打GPSTracker课程以获得纬度和经度。

GPSTracker gps = new GPSTracker(this);
double latitude = gps.getLatitude();
double longitude = gps.getLongitude();

这里是GPSTracker类

import android.app.AlertDialog;
import android.app.Service;
import android.content.Context;
import android.content.DialogInterface;
import android.content.Intent;
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;

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) {
      }
     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 DialogHelp Title
    alertDialog.setTitle("GPS is settings");

    // Setting DialogHelp 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) {
    float bestAccuracy = -1f;
    if (location.getAccuracy() != 0.0f
        && (location.getAccuracy() < bestAccuracy) || bestAccuracy == -1f) {
            locationManager.removeUpdates(this);
    }
    bestAccuracy = location.getAccuracy();
 }

@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;
}

Answer 2

您可以使用此代码获取没有地图的位置。

    startGPSBtn.setOnClickListener(new OnClickListener() {

        @Override
        public void onClick(View v) {

                GPSTracker gps = new GPSTracker(YourTab.this);
                if (gps.canGetLocation()) {
                    getLocation(startGPSBtn ,gps);
                    startGPSLatitude = String.valueOf(gps.getLatitude());
                    startGPSLongitude = String.valueOf(gps.getLongitude());
                } else {
                    gps.showSettingsAlert();
                }
            }
    });
    endGPSBtn.setOnClickListener(new OnClickListener() {

        @Override
        public void onClick(View v) {

                GPSTracker gps = new GPSTracker(YourTab.this);
                if (gps.canGetLocation()) {
                    getLocation(endGPSBtn, gps);
                    endGPSLatitude = String.valueOf(gps.getLatitude());
                    endeGPSLongitude = String.valueOf(gps.getLongitude());
                } else {
                    gps.showSettingsAlert();
                }

        }
    });

另外，您可以检查互联网是否可用，设备GPS是开启还是关闭。

如何在Android上使用google maps v2而不加载地图

2 个答案: