crash at an attempt to open a list

[rozcietrzewiacz]

This is the error that crashes the app each time I try to view a list of cards:

E/AndroidRuntime(11980): FATAL EXCEPTION: main
E/AndroidRuntime(11980): java.lang.NullPointerException
E/AndroidRuntime(11980):    at com.chrishoekstra.trello.model.TrelloModel.getNotificationCount(TrelloModel.java:228)
E/AndroidRuntime(11980):    at com.chrishoekstra.trello.adapter.CardAdapter.getView(CardAdapter.java:175)
E/AndroidRuntime(11980):    at android.widget.AbsListView.obtainView(AbsListView.java:1604)
E/AndroidRuntime(11980):    at android.widget.ListView.makeAndAddView(ListView.java:1795)
E/AndroidRuntime(11980):    at android.widget.ListView.fillDown(ListView.java:718)
E/AndroidRuntime(11980):    at android.widget.ListView.fillFromTop(ListView.java:775)
E/AndroidRuntime(11980):    at android.widget.ListView.layoutChildren(ListView.java:1646)
E/AndroidRuntime(11980):    at android.widget.AbsListView.onLayout(AbsListView.java:1434)
E/AndroidRuntime(11980):    at android.view.View.layout(View.java:7175)