Simple pass data to a listview-adapter class

I am trying to pass data from one activity to another and then on my listview adapter getView to also pull that same data. sample code public String getuser() { return getIntent().getStringExtra("username").toString(); } and in my listview adapter class wolog obj = new wolog(); String username = [login to view URL](); error i get is Attempt to invoke virtual method '[login to view URL] [login to view URL]()' on a null object reference but it is not null