GSP not working after restarting my mobile

I am developing an application as I need to find the current location values. For this I have enabled gps programmatically. now i turned off and on my cell phone. Now I cannot get the current location values, but the gps of the device is on.

i found this issue in (motorola 2.3.3, htc 2.3.4 and nexus 4.2.1)

i used the following code.

String provider = Settings.Secure.getString(getContentResolver(),Settings.Secure.LOCATION_PROVIDERS_ALLOWED);

    if(!provider.contains("gps")){ //if gps is disabled
        final Intent poke = new Intent();
        poke.setClassName("com.android.settings", "com.android.settings.widget.SettingsAppWidgetProvider"); 
        poke.addCategory(Intent.CATEGORY_ALTERNATIVE);
        poke.setData(Uri.parse("3")); 
        sendBroadcast(poke);

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

Criteria criteria = new Criteria();
criteria.setAccuracy(Criteria.ACCURACY_FINE);
List<String> provider = locationManager.getProviders(true);
Location location = null;
for (int i=provider.size()-1; i>=0; i--) 
{
       location = locationManager.getLastKnownLocation(provider.get(i));
       if (location != null) break;

if (location != null) 
   {
      String latitude=String.valueOf(location.getLatitude());
      String longitude=String.valueOf(location.getLongitude());    
   }