Question

我想显示纬度和经度我当前的位置.. 为此而不是在谷歌搜索，我搜索了SO。

我只是想显示我当前的位置纬度和经度。

请参阅下面的代码：

public class LocationGetter extends Activity {

@Override

public void onCreate(Bundle savedInstanceState)
{

super.onCreate(savedInstanceState);

TextView tv = new TextView(this);

LocationManager mlocManager = 
                (LocationManager) getSystemService(Context.LOCATION_SERVICE);

LocationListener mlocListener = new LocationManagerHelper();

mlocManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, 30000, 100,mlocListener);

if (mlocManager.isProviderEnabled(LocationManager.GPS_PROVIDER)) {
        tv.append("Latitude:- " + LocationManagerHelper.getLatitude()
                + '\n');
        tv.append("Longitude:- " + LocationManagerHelper.getLongitude()
                + '\n');

        Log.i("MyLocation1",Double.toString(LocationManagerHelper.getLatitude())+" "+Double.toString(LocationManagerHelper.getLongitude()));

} else {
    tv.setText("GPS is not turned on...");
}

/** set the content view to the TextView */
setContentView(tv);

}

/* Class My Location Listener */

public static class LocationManagerHelper implements LocationListener {

    private static double latitude;
    private static double longitude;

    @Override
    public void onLocationChanged(Location loc) {
        latitude = loc.getLatitude();
        longitude = loc.getLongitude();
        Log.i("MyLocation",Double.toString(latitude)+" "+Double.toString(longitude));
    }

    @Override
    public void onProviderDisabled(String provider) { }

    @Override
    public void onProviderEnabled(String provider) { }

    @Override
    public void onStatusChanged(String provider, int status, Bundle extras) {
        // TODO Auto-generated method stub

    }

    public static double getLatitude() {
        return latitude;
    }

    public static double getLongitude() {
        return longitude;
    }

}

}

我还在清单文件中添加了权限：

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

查看我得到的输出：

enter image description here

我哪里错了？我不明白，它是一个简单的代码，为什么它不起作用？

Answer 1

我刚刚验证了您的代码并且它可以使用这些更改，您只需要将tv.append()调用移动到每次调用的onLocationChanged()方法，如果您不使用它CallBack，那么你将只得到第一个设定值，它只执行一次。

        public void onLocationChanged(Location loc) {
            latitude = loc.getLatitude();
            longitude = loc.getLongitude();
            Log.i("MyLocation",Double.toString(latitude)+" "+Double.toString(longitude));
            tv.append("Latitude:- " + LocationManagerHelper.getLatitude()
                    + '\n');
            tv.append("Longitude:- " + LocationManagerHelper.getLongitude()
                    + '\n');

            Log.i("MyLocation1",Double.toString(LocationManagerHelper.getLatitude())+" "+Double.toString(LocationManagerHelper.getLongitude()));

        }

我在AndroidManifest.xml

中使用了这些权限

<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />    
<uses-permission android:name="android.permission.ACCESS_LOCATION_EXTRA_COMMANDS" />
<uses-permission android:name="android.permission.ACCESS_MOCK_LOCATION" />    
<uses-permission android:name="android.permission.CONTROL_LOCATION_UPDATES" />

您可以查看这些内容并过滤掉您不感兴趣的内容。我使用了here下载的.gpx文件

我已经在Android 2.2上测试了它， Location Updates working

Answer 2

你在Onlocationchanged中有位置

 public void onLocationChanged(Location loc) {
    latitude = loc.getLatitude();
    longitude = loc.getLongitude();
    Log.i("MyLocation",Double.toString(latitude)+" "+Double.toString(longitude));
  }

因此，仅当从当前位置进行更改时才会显示纬度和经度。用于检查您是否给出了经度和经度并从DDMS中的模拟器控件发送，然后运行您的程序。它将显示位置

enter image description here

Answer 3

如果您在设备中运行此程序，则它会显示纬度和经度0.0，直到我们更改位置。您必须从当前位置移动至少10米才能看到输出。因为没有更改当前位置onLocationChange()方法不会触发，输出将为0.0

Answer 4

使用LocationManager。

LocationManager lm = (LocationManager)getSystemService(Context.LOCATION_SERVICE); 
Location location = lm.getLastKnownLocation(LocationManager.GPS_PROVIDER);
double longitude = location.getLongitude();
double latitude = location.getLatitude();

对getLastKnownLocation()的调用不会阻止 - 这意味着如果当前没有可用的位置，它将返回null - 因此您可能希望查看将LocationListener传递给相反，requestLocationUpdates() method会为您提供位置的异步更新。

private final LocationListener locationListener = new LocationListener() {
    public void onLocationChanged(Location location) {
        longitude = location.getLongitude();
        latitude = location.getLatitude();
    }
}

lm.requestLocationUpdates(LocationManager.GPS, 2000, 10, locationListener);

如果您想使用GPS，则需要为您的应用程序提供ACCESS_FINE_LOCATION permission。

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

您可能还想在GPS不可用时添加ACCESS_COARSE_LOCATION permission，并使用getBestProvider() method选择您的位置提供商。

Answer 5

我认为使用模拟器无法获得GPS坐标。如果您正在使用移动设备，请在建筑物外部尝试GPS。有时你不会在建筑物内获得GPS坐标。如果那个时候你也失败了，那么我将发布我们成功的代码。

以下代码我刚刚测试了它的作品..

 import android.app.Activity;
 import android.content.Context;
 import android.location.Location;
 import android.location.LocationListener;
 import android.location.LocationManager;
 import android.os.Bundle;
 import android.widget.Toast;

 public class GetGPS extends Activity {

String GPSPROVIDER = LocationManager.GPS_PROVIDER;
private  static final long MIN_GEOGRAPHIC_POOLING_TIME_PERIOD = 10000;
private  static final float MIN_GEOGRAPHIC_POOLING_DISTANCE = (float)5.0;

public LocationManager gpsLocationManager;

static Context context = null;
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);

    context = this;

    /*Get a listener for GPS*/
    LocationListener gpsLocationListener = null;

    gpsLocationListener = new GpsLocationListener(this);

    /*Start Location Service for GPS*/
    gpsLocationManager = (LocationManager) this.getSystemService(Context.LOCATION_SERVICE);

    /*Register GPS listener with Location Manager*/
    gpsLocationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, 
            MIN_GEOGRAPHIC_POOLING_TIME_PERIOD,
            MIN_GEOGRAPHIC_POOLING_DISTANCE, gpsLocationListener);

    boolean isavailable = gpsLocationManager.isProviderEnabled(GPSPROVIDER);

    if(isavailable) {

        Location loc = gpsLocationManager.getLastKnownLocation("gps");

        if(loc != null) {
            double latitude = loc.getLatitude();
            double longitude = loc.getLongitude();

            Toast.makeText(GetGPS.this,"Longitude is  "+longitude + "   Latitude is   "+latitude, Toast.LENGTH_LONG).show();

        }
    }

}

public static class GpsLocationListener implements LocationListener {


    public GpsLocationListener(Context context){

    }

    public void onLocationChanged(Location loc) {

        if (loc != null) {

            double latitude = loc.getLatitude();
            double longitude = loc.getLongitude();

            Toast.makeText(context,"Longitude is  "+longitude + "   Latitude is   "+latitude, Toast.LENGTH_LONG).show();

        }

    }//End of onLocationChanged Method

    @Override
    public void onProviderDisabled(String provider) {

    }//End of onProviderDisabled Method

    @Override
    public void onProviderEnabled(String provider) {

    }//End of onProviderEnabled Method

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


    }//End of onStatusChanged Method

}//End of GpsLocationListener class
}

我通过将设备从一个地方移动到另一个地方来测试这个......

我希望它会有所帮助..

在Android中获取当前位置的问题

5 个答案: