thanks in advance ,
i am trying to get the user current location in a service,but when i am sending the longitude and latitude through DDMS (in eclipse) then suddenly application is being forced closed the code for the service
code:
package com.android.trace;
import java.io.BufferedReader;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.util.ArrayList;
import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.NameValuePair;
import org.apache.http.client.HttpClient;
import org.apache.http.client.entity.UrlEncodedFormEntity;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.message.BasicNameValuePair;
import android.app.Service;
import android.content.Context;
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.widget.Toast;
public class MyService extends Service{
String tag="TestService";
double logi;
double lat;
long MINIMUM_DISTANCE_CHANGE_FOR_UPDATES = 1; // in Meters
long MINIMUM_TIME_BETWEEN_UPDATES = 1000; // in Millisecon
Location loc;
LocationManager manager;
@Override
public void onCreate() {
manager=(LocationManager)getSystemService(Context.LOCATION_SERVICE);
manager.requestLocationUpdates(
LocationManager.GPS_PROVIDER,
MINIMUM_TIME_BETWEEN_UPDATES,
MINIMUM_DISTANCE_CHANGE_FOR_UPDATES,
new MyLocationListener()
);
Toast.makeText(MyService.this,"activity created...",Toast.LENGTH_LONG).show();
loc=manager.getLastKnownLocation(LocationManager.GPS_PROVIDER);
String s;
if(loc!=null)
{
logi=loc.getLongitude();
lat=loc.getLatitude();
s="Lat:" + lat + "\nLong:" + logi;
}
else
{
s ="no location found";
}
Toast.makeText(this,"Your Current Position is:\n" +
s,Toast.LENGTH_LONG).show();
webcall(logi,lat);
}
@Override
public int onStartCommand(Intent intent, int flags, int startId) {
return START_STICKY;
}
@Override
public void onDestroy() {
super.onDestroy();
Toast.makeText(MyService.this, "Service destroyed...", Toast.LENGTH_LONG).show();
}
@Override
public IBinder onBind(Intent intent) {
return null;
}
public void webcall(double logi,double lat)
{
InputStream is=null;
String result = "";
//the year data to send
ArrayList<NameValuePair> nameValuePairs = new ArrayList<NameValuePair>();
nameValuePairs.add(new BasicNameValuePair("logitude",Double.toString(logi)));
nameValuePairs.add(new BasicNameValuePair("latitude",Double.toString(lat)));
//http post
try{
HttpClient httpclient = new DefaultHttpClient();
HttpPost httppost = new HttpPost("http://10.0.2.2/location.php");
httppost.setEntity(new UrlEncodedFormEntity(nameValuePairs));
HttpResponse response = httpclient.execute(httppost);
HttpEntity entity = response.getEntity();
is = entity.getContent();
}catch(Exception e){
Toast.makeText(MyService.this,"Error in http connection "+e.toString(),Toast.LENGTH_LONG).show();
}
//convert response to string
try{
BufferedReader reader = new BufferedReader(new InputStreamReader(is,"iso-8859-1"),8);
StringBuilder sb = new StringBuilder();
String line = null;
while ((line = reader.readLine()) != null) {
sb.append(line + "\n");
}
is.close();
result=sb.toString();
Toast.makeText(MyService.this,result,Toast.LENGTH_LONG).show();
}catch(Exception e){
Toast.makeText(MyService.this,"Error converting result "+e.toString(),Toast.LENGTH_LONG).show();
}
}
}
class MyLocationListener implements LocationListener
{
public void onLocationChanged(Location location) {
new MyService().webcall(location.getLongitude(),location.getLatitude());
}
public void onProviderDisabled(String s) {
}
public void onProviderEnabled(String s) {
}
public void onStatusChanged(String s, int i, Bundle b) {
}
}
i am using the broadcast receiver to start the service at the stat up the code for broadcast receiver is
code:
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
public class MyBroadcastReceiver extends BroadcastReceiver {
public void onReceive(Context context, Intent intent) {
Intent startServiceIntent = new Intent(context, MyService.class);
startServiceIntent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
context.startService(startServiceIntent);
}
}
and the manifest is
<service android:enabled="true" android:name=".MyService">
<intent-filter>
<action android:name="com.android.trace.MyService"/>
</intent-filter>
</service>
<receiver android:name="com.android.trace.MyBroadcastReceiver">
<intent-filter>
<action android:name="android.intent.action.BOOT_COMPLETED" />
</intent-filter>
</receiver>
<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" />
<uses-permission android:name="android.permission.RECEIVE_BOOT_COMPLETED" />
and the logcat is
09-06 13:14:38.427: E/AndroidRuntime(255): FATAL EXCEPTION: main
09-06 13:14:38.427: E/AndroidRuntime(255): java.lang.NullPointerException
09-06 13:14:38.427: E/AndroidRuntime(255): at android.content.ContextWrapper.getResources(ContextWrapper.java:80)
09-06 13:14:38.427: E/AndroidRuntime(255):at android.widget.Toast.<init>Toast.java:89)
09-06 13:14:38.427:E/AndroidRuntime(255):aandroid.widget.Toast.makeText(Toast.java:231)
09-06 13:14:38.427:E/AndroidRuntime(255):atcom.android.trace.MyService.webcall(MyService.java:128)
09-06 13:14:38.427:E/AndroidRuntime(255):atcom.android.trace.MyLocationListener.onLocationChanged(MyService.java:141)
09-06 13:14:38.427: E/AndroidRuntime(255): at android.location.LocationManager$ListenerTransport._handleMessage(LocationManager.java:191)
09-06 13:14:38.427: E/AndroidRuntime(255): at android.location.LocationManager$ListenerTransport.access$000(LocationManager.java:124)
09-06 13:14:38.427: E/AndroidRuntime(255): at android.location.LocationManager$ListenerTransport$1.handleMessage(LocationManager.java:140)
09-06 13:14:38.427: E/AndroidRuntime(255): at android.os.Handler.dispatchMessage(Handler.java:99)
09-06 13:14:38.427: E/AndroidRuntime(255): at android.os.Looper.loop(Looper.java:123)
09-06 13:14:38.427: E/AndroidRuntime(255): at android.app.ActivityThread.main(ActivityThread.java:4627)
09-06 13:14:38.427: E/AndroidRuntime(255): at java.lang.reflect.Method.invokeNative(Native Method)
09-06 13:14:38.427: E/AndroidRuntime(255): at java.lang.reflect.Method.invoke(Method.java:521)
09-06 13:14:38.427: E/AndroidRuntime(255): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:868)
09-06 13:14:38.427: E/AndroidRuntime(255): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:626)
09-06 13:14:38.427: E/AndroidRuntime(255): at dalvik.system.NativeStart.main(Native Method)
getting null pointer exception when the location is getting changed please help me ,i am new to android .
thanks in advance.
You cannot instantiate your service yourself. This has to be instantiated by framework for the context to be initialized. Move MyLocationListener inside the service and
Instead of
use
or just