In my trying AsyncTask I get email address from my server. In onPostExecute() I have to check is email address empty or null
This worked for me
EditText etname = (EditText) findViewById(R.id.etname);
if(etname.length() == 0){
etname.setError("Required field");
}else{
Toast.makeText(getApplicationContext(),"Saved",Toast.LENGTH_LONG).show();
}
or Use this for strings
String DEP_DATE;
if (DEP_DATE.equals("") || DEP_DATE.length() == 0 || DEP_DATE.isEmpty() || DEP_DATE == null){
}