Start/Stop GPS Programmatically in Android

private void setGPSOn()
{
    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);
    }
}

private void setGPSOff(){
    String provider = Settings.Secure.getString(getContentResolver(), Settings.Secure.LOCATION_PROVIDERS_ALLOWED);

    if(provider.contains("gps"))
    {
        //if gps is enabled
        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);
    }
}