Get Null In Asynctask

my AsyncTask codes return null when try to login. I got confused, why on device it can throw the toast 'return null...' but on emulator it force close, anyone please help me to fix

Solution 1:

You're confusing 'response' with 'result'. In onPostExecute(String result) 'result' is the result from your asynchronous execution in doInBackground(). The response member variable of LoginTask is never used and I do not see why you'd want it at all. Remove it and use 'result'.

Solution 2:

Log.d("Response",response); response isnull. 

In tryLogin you are returning NULL if there is an exception. Try changing it to some value and test again.

catch(IOException e)
{
     e.printStackTrace();
      Log.d("Error",e.getMessage());
      returnnull;
 }