SharedPreferences nullPointerException when saving strings

Question

I am working launcher for android. At the moment I am working for address book(yes I want to include it to my launcher), but I am getting NullPointerException. Here

Answer 1

If you use editor.putString(number,button);, 'number' is your key and 'button' is your default value.

If you want to retrieve the value of 'number' in your SharedPreferences, you should call getString(key, defValue) as follow :

return pres.getString(number, "");