I am creating an application to find the users current location. I referred this link What is the simplest and most robust way to get the user's current location on Android?
to create my app. My problem i have tried with both the providers, but it didn't detect any providers and the result is always location=null returns. Why this problem and how can i get the location in my phone.? Thanks in advance...
My code goes here This is MyLocation.java class
package com.example.locationupadates;
import java.util.Timer;
import java.util.TimerTask;
import android.content.Context;
import android.location.Location;
import android.location.LocationListener;
import android.location.LocationManager;
import android.os.Bundle;
import android.util.Log;
public class MyLocation {
Timer timer1;
LocationManager lm;
LocationResult locationResult;
boolean gps_enabled=false;
boolean network_enabled=false;
public boolean getLocation(Context context, LocationResult result)
{
//I use LocationResult callback class to pass location value from MyLocation to user code.
locationResult=result;
if(lm==null)
lm = (LocationManager) context.getSystemService(Context.LOCATION_SERVICE);
//exceptions will be thrown if provider is not permitted.
try{gps_enabled=lm.isProviderEnabled(LocationManager.GPS_PROVIDER);
Log.v("Ansar",""+"Network Enabled");}catch(Exception ex){}
try{network_enabled=lm.isProviderEnabled(LocationManager.NETWORK_PROVIDER);
Log.v("Ansar",""+"Network Enabled");}catch(Exception ex){}
//don't start listeners if no provider is enabled
if(!gps_enabled && !network_enabled){
Log.v("Ansar",""+"Not anything Enabled");
return false;
}
if(gps_enabled){
lm.requestLocationUpdates(LocationManager.GPS_PROVIDER, 0, 0, locationListenerGps);
Log.v("Ansar",""+"Location Listener Gps");
} if(network_enabled){
lm.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, 0, 0, locationListenerNetwork);
Log.v("Ansar",""+"Location Listener Network");
} timer1=new Timer();
timer1.schedule(new GetLastLocation(), 20000);
return true;
}
LocationListener locationListenerGps = new LocationListener() {
public void onLocationChanged(Location location) {
timer1.cancel();
locationResult.gotLocation(location);
lm.removeUpdates(this);
lm.removeUpdates(locationListenerNetwork);
Log.v("Ansar",""+location.getLongitude());
}
public void onProviderDisabled(String provider) {}
public void onProviderEnabled(String provider) {}
public void onStatusChanged(String provider, int status, Bundle extras) {}
};
LocationListener locationListenerNetwork = new LocationListener() {
public void onLocationChanged(Location location) {
timer1.cancel();
locationResult.gotLocation(location);
lm.removeUpdates(this);
lm.removeUpdates(locationListenerGps);
}
public void onProviderDisabled(String provider) {}
public void onProviderEnabled(String provider) {}
public void onStatusChanged(String provider, int status, Bundle extras) {}
};
class GetLastLocation extends TimerTask {
@Override
public void run() {
lm.removeUpdates(locationListenerGps);
lm.removeUpdates(locationListenerNetwork);
Location net_loc=null, gps_loc=null;
if(gps_enabled)
gps_loc=lm.getLastKnownLocation(LocationManager.GPS_PROVIDER);
if(network_enabled)
net_loc=lm.getLastKnownLocation(LocationManager.NETWORK_PROVIDER);
//if there are both values use the latest one
if(gps_loc!=null && net_loc!=null){
if(gps_loc.getTime()>net_loc.getTime())
locationResult.gotLocation(gps_loc);
else
locationResult.gotLocation(net_loc);
return;
}
if(gps_loc!=null){
locationResult.gotLocation(gps_loc);
return;
}
if(net_loc!=null){
locationResult.gotLocation(net_loc);
return;
}
locationResult.gotLocation(null);
}
}
public static abstract class LocationResult{
public abstract void gotLocation(Location location);
}
}
MainActivity.java
package com.example.locationupadates;
import android.app.Activity;
import android.location.Location;
import android.os.Bundle;
import android.util.Log;
import android.view.Menu;
import android.widget.TextView;
import com.example.locationupadates.MyLocation.LocationResult;
public class MainActivity extends Activity {
TextView tv;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
tv=(TextView) findViewById(R.id.tv);
Log.d("Ansar",""+"oncreate");
LocationResult locationResult = new LocationResult(){
@Override
public void gotLocation(Location location){
Log.v("Ansar",""+location.getLongitude());
tv.setText("location:"+location+"latitude: "+location.getLatitude()+"longitude "+location.getLongitude());
}
};
MyLocation myLocation = new MyLocation();
myLocation.getLocation(this, locationResult);
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
}
Manifest.xml
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.locationupadates"
android:versionCode="1"
android:versionName="1.0" >
<uses-sdk
android:minSdkVersion="10"
android:targetSdkVersion="18" />
<uses-permission android:name="android.permission.INTERNET"/>
<application
android:allowBackup="true"
android:icon="@drawable/ic_launcher"
android:label="@string/app_name"
android:theme="@style/AppTheme" >
<activity
android:name="com.example.locationupadates.MainActivity"
android:label="@string/app_name" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
</manifest>
Exception
02-21 11:39:05.963: W/dalvikvm(18909): threadid=11: thread exiting with uncaught exception (group=0x410e4390)
02-21 11:39:05.963: E/AndroidRuntime(18909): FATAL EXCEPTION: Timer-0
02-21 11:39:05.963: E/AndroidRuntime(18909): java.lang.NullPointerException
02-21 11:39:05.963: E/AndroidRuntime(18909): at com.example.locationupadates.MainActivity$1.gotLocation(MainActivity.java:23)
02-21 11:39:05.963: E/AndroidRuntime(18909): at com.example.locationupadates.MyLocation$GetLastLocation.run(MyLocation.java:102)
02-21 11:39:05.963: E/AndroidRuntime(18909): at java.util.Timer$TimerImpl.run(Timer.java:284)
02-21 11:39:05.963: W/dalvikvm(18909): threadid=11: thread exiting with uncaught exception (group=0x410e4390)
02-21 11:39:05.963: E/AndroidRuntime(18909): FATAL EXCEPTION: Timer-0
02-21 11:39:05.963: E/AndroidRuntime(18909): java.lang.NullPointerException
02-21 11:39:05.963: E/AndroidRuntime(18909): at com.example.locationupadates.MainActivity$1.gotLocation(MainActivity.java:23)
02-21 11:39:05.963: E/AndroidRuntime(18909): at com.example.locationupadates.MyLocation$GetLastLocation.run(MyLocation.java:102)
02-21 11:39:05.963: E/AndroidRuntime(18909): at java.util.Timer$TimerImpl.run(Timer.java:284)
