獲取Android中的確切緯度和經度

Question

我想獲取手機的經緯度，並將這些位置詳細信息發送到一個電子郵件地址。它正在工作，但我無法獲得當前位置的確切經度和緯度。我不想使用地圖視圖，我試圖使用GPS，但我無法正確使用它。這是我的代碼：

package com.example.mapq; 

import android.location.Criteria; 
import android.location.Location; 
import android.location.LocationListener; 
import android.location.LocationManager; 
import android.os.Bundle; 
import android.app.Activity; 
import android.content.Context; 
import android.content.Intent; 
import android.view.View; 
import android.view.View.OnClickListener; 
import android.widget.Button; 
import android.widget.TextView; 

public class MapActivity extends Activity implements LocationListener{ 
LocationManager lm; 
TextView lt, ln; 
Button b1; 
String provider; 
Location l; 
@Override 
protected void onCreate(Bundle savedInstanceState) { 
super.onCreate(savedInstanceState); 
setContentView(R.layout.activity_map); 
ln=(TextView)findViewById(R.id.lng); 
lt=(TextView)findViewById(R.id.lat); 
b1=(Button) findViewById(R.id.button1); 

lm=(LocationManager)this.getSystemService(Context.LOCATION_SERVICE); 
Criteria c=new Criteria(); 
//criteria object will select best service based on 
//Accuracy, power consumption, response, bearing and monetary cost 
//set false to use best service otherwise it will select the default Sim network 
//and give the location based on sim network 
//now it will first check satellite than Internet than Sim network location 
provider=lm.getBestProvider(c, false); 
//now you have best provider 
//get location 
l=lm.getLastKnownLocation(provider); 
if(l!=null) 
{ 
//get latitude and longitude of the location 
final double lng=l.getLongitude(); 
final double lat=l.getLatitude(); 
//display on text view 
ln.setText(""+lng); 
lt.setText(""+lat); 

b1.setOnClickListener(new OnClickListener() { 

@Override 
public void onClick(View v) { 
Intent emailIntent = new Intent(Intent.ACTION_SEND); 
emailIntent.putExtra(Intent.EXTRA_EMAIL, new String[]{"mallikarjuna8511820@gmail.com"}); 
emailIntent.putExtra(Intent.EXTRA_CC, new String[]{"mallikarjuna8511820@gmail.com"}); 
emailIntent.putExtra(Intent.EXTRA_SUBJECT, "subject"); 
emailIntent.putExtra(Intent.EXTRA_TEXT, "body"); 
emailIntent.putExtra(android.content.Intent.EXTRA_TEXT, 
       "http://maps.google.com/maps?q=loc:" + lat +","+ lng); 
emailIntent.setType("plain/text"); 
startActivity(Intent.createChooser(emailIntent, "choose email client...")); 

     } 
    }); 
} 
else 
{ 
ln.setText("No Provider"); 
lt.setText("No Provider"); 
} 
} 
//If you want location on changing place also than use below method 
//otherwise remove all below methods and don't implement location listener 
@Override 
public void onLocationChanged(Location arg0) 
{ 
double lng=l.getLongitude(); 
double lat=l.getLatitude(); 
ln.setText(""+lng); 
lt.setText(""+lat); 
} 

@Override 
public void onProviderDisabled(String arg0) { 
// TODO Auto-generated method stub 
} 
@Override 
public void onProviderEnabled(String arg0) { 
// TODO Auto-generated method stub 
} 

@Override 
public void onStatusChanged(String arg0, int arg1, Bundle arg2) { 
// TODO Auto-generated method stub 
} 
} 

Answer 1

您需要requestLocationUpdates地方在你的代碼一樣的onCreate /恢復，如：

lm = (LocationManager) getSystemService(LOCATION_SERVICE); 
lm.requestLocationUpdates(LocationManager.GPS_PROVIDER, 
        mUpdatePeriod * 1000, mMinResendDistance, this); 

其中的典型值可能是：

private float mMinResendDistance = 10.0f; 
private int mUpdatePeriod; // in SECONDS 

。